Region.	Classification of species.						Proportion of non-adaptive and adaptive species.		Total number of species dealt with.
	Non-adaptive.				Adaptive.
	First group.		Second group.		Third group.		Percentage of non-adaptive species.	Percentage of adaptive species.
	Number.	Per cent.	Number.	Per cent.	Number.	Per cent.
Pacific Islands	27	40	10	15	30	45	55	45	67
Pacific Islands, tropical America, and Indo-Malaya	28	35	12	15	40	50	50	50	80

Note.—If to the last we add the eight British shore plants, the buoyant fruits of which are described in Chapter XII., three non-adaptive and five adaptive, we get a proportion of adaptive species for temperate and tropical regions of fifty-one per cent. This is probably fairly typical of the world generally; but it must be remembered by the reader that the author regards them all as non-adaptive. In that case, the table can be used for the numerical results of the three groups which are based only on structural characters without reference to any theory.

NOTE 46 (page 124)
 
On the Modes of Dispersal of the Genus Brackenridgea.

Seed-vessels of this genus found afloat in the New Guinea drift are described by Mr. Hemsley as having two curved cavities crossing each other one containing a seed, the other empty. “This empty cavity,” it is stated “gives the fruit its buoyancy” (Bot. Chall. Exped., iii., 289; plate 54) Dr. Beccari, in the English edition of his Wanderings in Borneo, p. 187, speaks of the closed air-containing cavities in the seed-vessels, or rather “stones,” of this genus as probably giving them buoyancy and thus enabling them to be dispersed by currents. He points out that the fleshy covering of these fruits would also aid their dispersal by birds. The Italian botanist implies that the two Bornean species grow in swamps. The Fijian species, as observed by me in flower in Vanua Levu, grew in the dry talasinga districts bordering the Mathuata coast, the locality where Seemann found the plant. One of the most recent accounts of the genus is given by Van Tieghem in his memoir on the Ochnaceæ in Ann. des. Sci. Nat. Bot., tome 16, 1902. According to him there are nine species, all from Malaya and New Guinea, with the exception of one in Fiji. Previous authors have also referred to Queensland and Zanzibar species. However, all the species have a limited distribution, a fact which plainly assigns to birds the principal share in the dispersal of the genus.

NOTE 47 (page 125)
 
On the Transport of Gourds by Currents

Small calabashes or bottle-gourds are not uncommonly to be found floating in the Fijian estuaries and stranded on the beaches; and I have also found them in the sea off the coasts. They are usually more or less globular, 3 or 4 inches across, and are evidently able to float for very long periods and to carry the seeds unharmed. Most of those I examined from the drift were dry inside and contained the seeds dried together into a loose ball about an inch in size. The seeds are not those figured in Gaertner’s De Fructibus et Seminibus, as belonging to Lagenaria vulgaris, and more resemble those of Cucurbita, but are non-buoyant. One of these gourds, picked up by me in the sea in Fiji, was placed in sea-water, and two months later was still floating buoyantly. After being then kept dry for seven months, it was broken open; and ten of the seeds were put in soil, two of them germinating in a few days.

In Ecuador gourds similar in size and shape were frequently observed by me floating in the drift of the Guayaquil River and stranded on the sea-beaches. The seeds are similarly caked together in a loose mass in the cavity of the fruit. Their characters indicate that they belong to another species of gourd; and they differ also from the Fijian seeds in their buoyancy, some of them in my experiments floating two months and afterwards germinating.

It has been known since the days of Ström and Gunnerus, two Norwegian naturalists of the 17th century, that gourds and calabashes are from time to time stranded with other Gulf-stream drift on the coasts of Norway. We learn from Sernander that those found are usually worked calabashes; but he alludes to one that was unworked and contained several seeds (see Sernander, p. 119).

It is scarcely likely that a seed-carrying gourd stranded on a beach would be able to establish the plant without the aid of man; but it seems highly probable that gourds have often been introduced into new countries by the currents and that man has afterwards cultivated them. These plants may be contrasted with that remarkable Cucurbit, Luffa insularum, a genuine littoral plant, the seeds of which, and not the fruits, are dispersed in the Pacific by the currents (see page 426).

NOTE 48 (page 126)
 
On the Useless Dispersal by Currents of the Fruits of the Oak (Quercus robur) and other Species of Quercus, and also of the Hazel (Corylus avellana)

The fruits of different species of Quercus are of not infrequent occurrence in the seed-drift both of the temperate and tropical regions, being brought down by the rivers to the sea and then stranded on the neighbouring beaches. They were amongst the drift gathered by Mr. Moseley in the open sea, 70 miles off the New Guinea coast (Bot. Chall. Exped., iv., 294). I found them on the beaches of Keeling Atoll where no oak exists, and on the beaches of the south coast of Java; whilst Prof. Schimper noticed them among the stranded drift of the Java Sea, and Prof. Penzig found them stranded on the shores of Krakatoa. They also came under my notice on the Sicilian beaches and on the Italian coast at Cumæ. Those of Quercus robur are to be found on the English beaches and in the autumn drift of the Thames, but they soon sink and disappear from river-drift. They are referred to by Dr. Sernander as frozen with other floating seeds in the ice of the Scandinavian rivers; but he evidently does not regard them as possessing much independent floating power.

Some years ago the author made a number of experiments on the buoyancy of the acorns of Quercus robur, and he formed the conclusion that when freshly collected not more than 4 to 8 per cent. of mature fruits will float in fresh-water, and not more than about 10 to 12 per cent. in sea-water, but that in either case they all sink in a day or two. Immature acorns float much longer, and it is these that mostly figure in the drift. However, unlike most fruits of little initial buoyancy the mature fruits gain considerable floating power by drying. Of some that had been kept for seven months 20 per cent. floated after four weeks in sea-water and 15 per cent. after 10 weeks.... It may be added that, according to Thuret, the fruits of Quercus ilex have little or no floating power.

The buoyancy of the fruits of Quercus is due entirely to the cavity left by the shrinking of the kernel. I never remember to have found one with a sound seed amongst the drift in England and Sicily; and I should doubt much whether those in the tropical drift retain their germinating powers. But, apart from this, the genus Quercus finds in its own constitution or habit the greatest obstacle in most species to the adoption of a littoral station. However, there are exceptional tendencies displayed by the evergreen oaks; and this is very significant, since in their xerophilous leaves they possess the preliminary qualification for a station near the sea. Quercus ilex, it is well known, shows a partiality for the sea-air, and Q. virens, the “live oak,” flourishes near the sea in the southern states of America, a maritime variety being distinguished by botanists. One of the willow-oaks of America, Q. phellos, which grows in swampy land, also has a beach variety.

The Hazel-tree (Corylus avellana) must be placed in the same category with Quercus. I found the empty nuts commonly amongst the stranded drift of the Sicilian and English beaches. The fruits were also frequently noticed by Dr. Sernander in the Scandinavian sea-drift; but he says nothing of their empty condition. Mr. Darwin remarks, in the Origin of Species, that he found that fresh hazel-nuts sank, but that after drying a long time they floated for ninety days and subsequently germinated. The floating-power is no doubt due to the cavity arising from the shrinking of the kernel, and it is to this cause that Dr. Sernander attributed the slight initial buoyancy observed by him. However, the hazel, like the common oak, lacks the habit that would fit it for a station by the sea, and, whatever capacity its fruits may possess for dispersal by currents, it is quite useless for the spread of the species.

NOTE 49 (page 131)
 
On the Distribution of Ipomœa pes capræ, Convolvulus soldanella, and Convolvulus sepium

Whilst Ipomœa pes capræ is cosmopolitan in the tropical zones, Convolvulus soldanella is cosmopolitan in both the north and south temperate zones; but, as might be expected, the two species at times meet and their areas overlap. Thus, according to Mr. Cheeseman (Trans. New Zealand Inst., xx., 1887), they meet in the Kermadec Islands, in the South Pacific, in about latitude 30°. From my observations on the coast of Chile it would seem that C. soldanella in its northward extension fails somewhere between Valparaiso and Coquimbo, that is to say, between 33° and 30° S. lat. Gay merely refers to the plant as existing in North Chile, which in his time would include the coast between 33° and 24° S. lat. It intrudes within the “thirties” on the coast of California and is found in Madeira in about 33° N. lat. Ipomœa pes capræ in its turn extends into subtropical regions, being recorded from the Kermadecs, as above noted, and from the Bermudas in 32° N. lat. Owing probably to special physical conditions of the coast, which are referred to in Chapter XXXII., this plant is evidently limited to the tropics on the west coast of South America. It did not come under my notice on the beaches of North Chile, and it is apparently not mentioned by Gay in his work on the Chilian flora.

Convolvulus sepium, the frequent inland associate of the littoral C. soldanella over the temperate regions of the globe, belongs to the same section of the genus (Calystegia). Its extraordinary occurrence by itself in the island of St. Paul, in the Southern Ocean, about fifty yards from the shore (Bot. Chall. Exped., ii., 153, 264), almost suggests that we have here a dimorphic species with a littoral and an inland form; and its existence in the Azores is in this connection very remarkable. It may be here noted that of three plants raised from seeds found in the beach-drift near Palermo two had the foliage of C. sepium and one of C. soldanella. Perhaps one of my readers, in imitation of De Vries with Œnothera, might be able to settle this point by raising some hundreds of seedlings from the seeds of the beach species. It is possible that the relation between these two species of Convolvulus may be in some respects akin to that between Cæsalpinia Bonducella and C. Bonduc, two littoral plants that accompany each other over much of the tropical zone.

The student of dispersal will, however, find some curious gaps in the distribution of Convolvulus soldanella even in the temperate regions; and it will be curious to observe how they affect the distribution of C. sepium. He will have to answer the query of De Candolle:... “Admitting, if one wishes, that the currents have transported this marine species, how comes it that it chances to be in the Pacific and in Europe, without occurring on the east coasts of America and on the east and west coasts of Africa?” (Geographie Botanique, ii., 1056). He will have to explain why some botanists give C. soldanella a habitat in the tropics, as in the Indian region. Schimper, who investigated this point, says that he arrived at no certain result (p. 127). See Notes 13 and 41 and pages 29, 91, for further remarks on these two species of Convolvulus.

NOTE 50 (pages 79, 132)
 
On the Structure of the Seeds and Fruits of Barringtonia

As regards the fruits and their coverings, the littoral and inland species of Fiji evidently fall into different sections, the first named (B. speciosa and B. racemosa) being distinguished by their outer fibrous husk, to which the buoyancy is due, the last-named (B. edulis and an undescribed species) possessing a hard stone surrounding the seed, and here the fruits sink or float only for limited periods.

The fruits of B. edulis have an outer almost fleshy covering, a little fibrous at the outside, and the hard ligneous “stone,” containing an edible seed, requires a hammer to break it. They float heavily for three or four weeks, whereas those of the littoral species float for many months. In the case of another inland species found by me growing as a small tree 12 feet high on the slopes of Mount Seatura in Vanua Levu at an elevation of 1,000 feet above the sea, the seed was similarly protected by a hard “stone” that could only be broken with an axe, and the fruit was non-buoyant, with thin and perishable outer coats.

This mountain species of Fiji, which I may name Barringtonia seaturæ, has the general habit of B. racemosa, with which the natives persisted in linking it; whilst the fruit and foliage come nearer to those of B. edulis. The leaves are entire, taper at the base, and have a petiole 1 inch long. The fruits are oblong, at least 3 inches in length, and are obscurely angled.

It would appear from Schimper’s description (p. 173) that the fruits of the Malayan Barringtonia excelsa possess both the hard stone-shell of the inland Fijian species and the dry air-bearing fibrous husk of the littoral species. This is of special interest, since the tree is both a coast and an inland species.

The following notes on the structure of the seeds of Barringtonia were made whilst I was drifting about in my canoe in the creeks of the Rewa delta in Fiji; and whatever may be their deficiencies they have the merit of having been written in the home of the plants.... When we cut across a seed like that of B. racemosa or B. speciosa, we observe that the different parts of the embryo are indistinguishable, being united into a homogeneous, firm, fleshy mass. But if we look closely we notice a central fusiform portion marked out from the surrounding parts by a faint line, along which a delicate membrane of vascular tissue has been developed. When “germination” begins, though, as the reader will subsequently perceive, this term is here hardly appropriate, the real nature of this singular structure becomes more apparent, as is indicated in the accompanying figure. The central fusiform portion proves to be the young plant without cotyledons and growing at either end to form the root and the stem. The delicate investing membrane becomes thicker and more apparent as germination proceeds, extending upwards and downwards with the growth of the stem and root and forming a cortical covering in either case. The investing fleshy portion of the seed, which is now separable with the fingers, remains attached to the lower part of the seedling for some time, being evidently a source of nutriment, and gives a bulbous appearance to the young plant. Young bulbous plants of B. racemosa, 1 to 2 feet high, are very common on the edge of Fijian mangrove swamps where the parent tree thrives. The seedlings of B. speciosa have the same appearance, but the outer fleshy part of the bulb is not so thick.

Diagrams illustrating the structure of the growing seeds of Barringtonia (two-thirds the natural size). That of B. speciosa represents a seed removed from a fruit displaying the young plant protruding two or three inches. That of B. racemosa represents the lower end of the seedling when the plant is eighteen inches high.

• a = the exorhiza.
• b = the neorhiza invested by the medullary sheath.

This structure of the seeds of Barringtonia speciosa and of B. racemosa was for a long time meaningless to me, until one day, whilst seated on the banks of the Lower Rewa, with a number of the sected seeds and bulbous seedlings gathered around, I reflected that the fruits of the latter species that floated past me in the river-drift were nearly always germinating. This called up “vivipary” to my mind; and as I looked at the Rhizophora seedlings dangling from the branches of the mangrove-trees close by, it occurred to me that this seed-structure might be the result of a lost viviparous habit. One apparently had to deal here not with an ordinary seed containing an embryo in the midst of albumen, but with a seed in an arrested stage of germination surrounded by a body that might perhaps prove homologous with the “cotyledonary body” of Rhizophora. The process of development that goes on without a break in Rhizophora, from the fertilisation of the ovule to the detachment of the seedling from the branch, was here, as I considered, arrested after germination had begun, but before the protrusion of the seedling from the fruit. With nearly all plants, as I reflected, there is a rest-stage of varying length, which might be called the seed-stage. With the mangrove-genera, Rhizophora and Bruguiera, I had convinced myself by a long series of observations, the results of which are given in Chapter XXX., that this rest-stage does not exist. It occurs, I argued, in Barringtonia, but only after germination has begun, and, therefore, displaced when compared with the typical seed-stage of most plants.

In this connection it may be noted that a difference in germinating behaviour might be expected between the two shore species on account of their difference in stations, Barringtonia speciosa growing on the sandy beach, and B. racemosa in the wet ground around a mangrove-swamp. There is a strong suspicion that the rest-stage in B. racemosa is very short, though I never found germination in progress on a tree (see Note 37). There is no doubt, on the other hand, that the rest-stage of B. speciosa is often, as with most other plants, very long. This, then, was my lesson from the Barringtonia fruits on the banks of the Rewa, and the question arose whether this interpretation of these curious seed-structures accorded with the opinion formed of their nature by botanists.

Curious seed-structures of this kind must have their significance in the history of the plant; and on returning to England I looked a little further into the matter. To follow up this kind of inquiry, however, would carry me far beyond the limits prescribed for this note, and I have only treated it here in a tentative fashion. Different botanists of eminence have paid attention to this subject, amongst them Roxburgh, Thomson, and Miers (see Dr. T. Thomson in Journ. Linn. Soc. Bot., vol. ii., p. 47, 1858, and Mr. J. Miers in Trans. Linn. Soc. Bot., vol. i., 1880). It would appear that the seed-structure of Barringtonia is also found in Careya, a genus of the same Myrtaceous tribe, and in Garcinia and other genera of the Guttiferæ, as well as in other inland plants.

Mr. Miers, after reviewing the opinions of his predecessors, gives the results of his own investigations. The solid embryo found in Barringtonia and many other genera consists, he observes, (a) of an external portion, the “exorhiza,” which nourishes the germinating seed and then dies away; (b) of an internal portion, the “neorhiza,” which, growing at each end, forms the central portion of the stem and root; and (c) the “medullary sheath” of Mirbel, that lies between the two, and is composed of elementary vascular tissue, which ultimately gives origin to the wood, bark, and leaves of the stem and yields woody fibre to the root. The exorhizal portion in some cases, as in Barringtonia acutangula, splits into four parts during germination. Mr. Miers compares this seed-structure with that of Rhizophora, employing the same terms, “neorhiza” for the internal portion which forms the seedling, and “exorhiza” for the external portion which merely nourishes it. However, I may add that the exorhizal portion in Rhizophora, as shown in Chapter XXX., is now regarded as formed by the coalesced cotyledons, and is termed the “cotyledonary body”; so that by implication the corresponding part of a Barringtonia seed should be regarded from the same standpoint.

It may be apposite to notice here that Barringtonia racemosa displays one capacity which does not appear to belong to B. speciosa. The branches stuck in wet soil throw out roots and establish themselves. This capacity of vegetative reproduction is turned to account by the Fijians, who make “live-fences” of this tree in wet localities.

NOTE 51 (page 135)
 
On a Common Inland Species of Scævola in Vanua Levu, Fiji

This is a tall shrub, or small tree, nine or ten feet high, which corresponds with S. floribunda, Gray, as far as Seemann describes it. It has small, black, juicy drupes, well suited for dispersal by birds, having no “suberous” mesocarp as in the shore species (S. Kœnigii), and no capacity for dispersal by currents. It grows, much like the Hawaiian inland species, in exposed situations where there is plenty of light, as on mountain-peaks, at the borders of forests, in open-wooded districts, and in the plains, and is to be found at all elevations from near the sea up to the highest mountain summit (3,500 feet) when the station is suitable. I noticed it on the higher slopes and frequently on the tops of nearly all the principal mountains that I climbed. It is evident that birds carry the “stones” from one mountain-peak to another, and no doubt they explain the presence of the species in Tonga. Dr. Seemann speaks of it as a beach plant in Viti Levu. The plant familiar to me in Vanua Levu is only on very rare occasions to be seen as an intruder in the beach-flora.

NOTE 52 (page 137).
 
On the Capacity for Dispersal by Currents of Colubrina oppositifolia, an Inland Hawaiian Tree

The seeds in my experiments sank within ten days; but they are not readily detached from the fruit, as in the case of the buoyant seeds of the littoral species (C. asiatica). The fruits, which may float for a week or two, break down, as Hillebrand observes, tardily and imperfectly, and could give but little assistance to dispersal by water.

We have in E. indica a widely distributed littoral species, ranging from India through Malaya to eastern Australia, and over nearly all the groups of the Pacific, reaching to Tahiti and the Marquesas, but not occurring in Hawaii. It is associated in Fiji and Tonga with another shore-species, E. ovalifolia, Roxb., found also in India and Malaya. I did not come on the second species in Fiji, and according to Seemann it is rare. It is possible that there is a genetic connection between the two; and it is noteworthy that in one case Seemann was uncertain (p. 426) whether the species was E. ovalifolia or only a variety of E. indica.

In different parts of their areas both these species may be found inland. This no doubt is to be connected with their occasional cultivation. The Polynesians who esteem E. indica for its handsome scarlet flowers and its scarlet seeds often plant it near their houses; but it is curious that if we look at the pages of Seemann, Horne, and one or two other botanical authors who have written on the Pacific, we find no reference to its littoral station, the first-named botanist merely characterising it in Fiji as occurring “wild or planted.”

However, in various localities in Fiji, as on the shores of Natewa Bay in Vanua Levu, Erythrina indica thrives as a characteristic beach tree. Dr. Reinecke speaks of it as widely spread on the Samoan coasts; and the French botanists refer to it as a tree of the Tahitian beaches. Prof. Schimper frequently mentions the two littoral species of Erythrina as amongst the components of the Malayan strand-flora. Dr. Treub, when he visited Krakatoa in 1886, three years after the eruption, noticed some young plants of Erythrina growing on the shore; whilst Prof. Penzig in 1897 found that both E. indica and E. ovalifolia had established themselves on the beach. Mr. Kurz again is quoted by Prof. Schimper (p. 170) as including E. indica amongst the “beach-jungle” of Pegu.

There is abundant evidence in support of the dispersal of the genus by currents. I have observed the seeds of Erythrina indica on the beaches of Keeling Atoll. Schimper noted Erythrina seeds amongst the stranded drift of the Java Sea. Treub remarked young plants of the genus growing on the shore of Krakatoa three years after the great eruption, and Penzig places Erythrina indica and E. ovalifolia amongst the beach-plants brought to Krakatoa through the agency of the currents. The seeds of E. indica not infrequently came under my observation stranded on the Fijian beaches and floating in the Rewa estuary; and in an experiment made in Fiji they still floated after five months in sea-water. Mr. Hemsley years ago formed the opinion, from the drift collections at Kew, that the genus was dispersed by the currents. I may here add in further illustration of this point that Erythrina seeds were found by me in South America floating in numbers in the Guayaquil estuary and stranded on the beaches of Ecuador.

It is noteworthy that, unlike some of the other shore-plants, Erythrina indica has at least three sets of names in the South Pacific. Thus it is known as Rara and Ndrala in Fiji, Ngatae in Samoa, Futuna, and Rarotonga, Atae in Tahiti, and Kenae in the Marquesas. The Samoan and Tahitian name recalls the Burmese name of Ka-thit, whilst the Marquesan word is suggestive of the Makassar name Kăne or Kanur. The Hawaiian name of E. monosperma is Wili-wili, which evidently has arisen from the screw-like movement of the open pod when thrown into the air. The same name in the form of Wiri-wiri is applied for a similar reason to Gyrocarpus Jacquini in Fiji. It is possible that the Polynesians have assisted the dispersal of the coast-species (E. indica); but the currents could have performed the distribution unaided, and the variety of aboriginal names is not in favour of human intervention.

With reference to the possible extermination by insects of Erythrina in Hawaii, it has been before remarked (p. 143) that this would not account for the survival of an inland species, such as E. monosperma in Hawaii. However, this species since the occupation of that group by the white man is on the road to extinction. Dr. Hillebrand observes that the species was much more common formerly than in his time (1851-1871), a result evidently due to the ravages of the common tropical mealy bug, a pest of relatively modern introduction (see Koebele in Stubb’s Agricultural Report on Hawaii). It may be added here that Cordia subcordata, a littoral tree, had been almost exterminated by the ravages of a small moth even in Dr. Hillebrand’s time. During my examination of the coasts of the large island of Hawaii, in 1896-7, I was shown several places not long before occupied by this tree; and, as indicated in Note 29, it only came under my notice in a few localities.

NOTE 54 (page 145)
 
On the Genus Canavalia

Of the three maritime species, C. obtusifolia, D.C., occurs on beaches all round the tropical zone. I was familiar with it on North Keeling Island in the Indian Ocean, in Fiji, and in Ecuador. C. ensiformis, D.C., is just as widely spread; but it is both inland and maritime in its station, and except when collecting it in the Solomon Islands I have had but little acquaintance with it. C. sericea (Gray) is a characteristic beach-plant in Fiji, but is infrequent. In Rarotonga, according to Cheeseman, it is a common littoral plant. It was also found in Tahiti by Banks and Solander, and is seemingly peculiar to the Pacific islands.

Besides C. ensiformis, the other two shore species may at times be found inland. Thus it is singular that the French botanists do not, as a rule, speak of C. sericea as a Tahitian beach plant; and Nadeaud only remarks, concerning its station, that it frequents the wooded slopes of the valleys of the interior. In North Keeling Island C. obtusifolia presented itself to me not only as a beach-creeper, its usual habit, but as a climber over the branches of the coast trees. In one locality in Vanua Levu I found a variety of this species growing on a hill a mile inland and about 700 feet above the sea. On one of the beaches it approached C. sericea in some of its characters, as in the form of the calyx and in the hairiness.

Although the seeds of C. obtusifolia have long been known to be dispersed by the currents, having been found in Moseley’s collections of floating drift off the New Guinea coast (Bot. Chall. Exp., IV, 291), they displayed remarkable fickleness when experimented on by me in Fiji. As a rule, however, about 10 per cent. sank at once in sea-water, 50 per cent. floated after three weeks, and 10 per cent. after twelve weeks. Of seeds that had been kept three years, 50 per cent. floated after eleven weeks. The seeds are to be found in numbers amongst the stranded drift of the Fijian and Ecuador beaches, and I noticed them also afloat in the Rewa estuary of Fiji.

I tested the floating-power of the seeds of C. sericea in Fiji, and found that half of them remained afloat after sixty days. On the seeds of C. ensiformis I have not experimented; but their buoyancy is indicated by the frequent occurrence of the plant on the Solomon Island coral islets (Guppy’s Solomon Islands, pp. 290, 292, 296), and probably the Canavalia seeds identified at Kew from my drift collections on these islets belong to this species. Schimper (p. 166) refers to the seeds of a Canavalia in Java that were still afloat after ten weeks. These littoral plants are indebted for the floating capacity of the seed to the buoyant kernel.

NOTE 55 (page 42 and Note 20)
 
The Inland Extension of Scævola Kœnigii

Scævola sericea (Forst.), a hairy variety of this littoral plant, will probably prove in some localities to be the inland form of the species. Dr. Reinecke, who mentions only this variety for Samoa, says that it is found in very moist ground in river-ravines, and no other station is referred to. It would seem that both the glabrous and hairy forms occur in Hawaii. Dr. Seemann speaks of the hairy variety as littoral in Fiji.

NOTE 56 (page 149)
 
On the Capacity for Dispersal by Currents of Sophora tomentosa, S. chrysophylla, and S. tetraptera

(1) Sophora tomentosa, Linn.—The moniliform pods will float for few weeks, but it is to the seeds liberated by the breaking down of the pod that the wide dispersal of this beach-plant by the currents is due. When experimenting on the freshly obtained seeds in Fiji I found that four-fifths of them floated after three months in sea-water. With seeds that had been kept for three years, half floated after twelve months and retained their sound condition. The seeds owe their floating power to the buoyant kernel.

(2) Sophora chrysophylla, Seem.—The dry pods of this Hawaiian mountain species float between one and two weeks in sea-water, but being brittle they readily break down and the seeds escape. The seeds have no buoyancy even after drying for four years.

(3) Sophora tetraptera, Ait., from the coast of Chile.—After floating from ten to fourteen days in sea-water, the dry pods become sodden and begin to break up, the seeds escaping. Since, however, the pods tend to decay and break open on the tree they would not be available for dispersal by currents. Out of a number of freshly gathered seeds all floated buoyantly after a month in sea-water, when the experiment ended; and of seeds that had been kept over a year six out of ten floated after four months in sea-water, two of them germinating afterwards in soil. Like those of S. tomentosa the seeds possess buoyant kernels to which the floating power is due. On account of the hardness of the tests the seeds to ensure rapid germination require to be filed.

NOTE 57 (page 153)
 
On the Species of Ochrosia

Schumann distinguishes the following species:

(a) O. parviflora, Hensl., widely spread in the Pacific islands.

(b) O. compta, Schumann, confined to Hawaii and corresponding to var. B. of O. sandwicensis as given by Hillebrand.

(c) O. borbonica, Spr., synonym O. oppositifolia, Lam., from Mauritius and Madagascar to Java and Singapore.