Before discussing the inferences to be derived from this list, it may be well to notice some sources of error that, to a slight extent, affect the results. Although the season of our visit—the second half of May—was probably the best as regards the middle zone, it was too early to find the vegetation fully developed in the superior zone, especially on the highest ridges. It is probable that on this account the proportion of Umbelliferæ and Gramineæ found in the higher region is smaller than it would have been at a later season. At first sight it would appear that the shorter time that we were able to devote to an examination of the upper region, and the snow-storm which we encountered in the ascent to the Tagherot Pass, make the proportion of species found there, as shown by our lists, unduly small. There can be no doubt that we must have lost several species owing to these causes, but not enough to vitiate the results to a serious extent. In confirmation of this opinion it may be mentioned that although a native employed by M. Cosson has since made a large collection in the same part of the Great Atlas, and two German naturalists—MM. Rein and Fritsch—have visited the head of the Aït Mesan valley, very few species have been added to the Flora of the higher mountain region.

The first conclusion that strikes a botanist on examining the foregoing list is that the general type of the vegetation clearly marks this as belonging to the great Mediterranean Flora, which extends, with local peculiarities, from Persia and Belutschistan to the Atlantic Islands. Out of 248 genera represented in the Flora of these valleys there is not one which is not common to other portions of the Mediterranean region, and one only (Monanthes) is confined to the Great Atlas and the Canary and Cape de Verde Islands, all the others being types more or less widely spread. Further than this, the proportion borne by each of the prevailing natural orders to the whole vegetable population is pretty nearly the same that we are accustomed to find in the mountain regions of the Mediterranean region.

The materials for a comparison are unfortunately yet incomplete as regards many of the mountain districts which are best fitted for the purpose. The Flora of the Lesser Atlas of Algeria, as well as that of the rest of the French possessions in Africa, will be fully known only on the appearance of the important work promised by M. Cosson. The Flora of Spain by MM. Willkomm and Lange is yet unfinished, and there is the further difficulty that those authors have admitted a large number of plants to the rank of species which many botanists reckon only as varieties. M. Boissier’s great work, the ‘Flora Orientalis,’ is also unfinished, and no adequate materials exist for compiling lists of the plants of the Greek mountains, of those of Asia Minor, or of the Lebanon chain, all of which would afford interesting materials for comparison. In the following table I have taken for comparison the Flora of the Sierra Nevada, with the neighbouring mountains of the ancient kingdom of Granada above the level of about 800 metres, compiled from Boissier’s ‘Voyage botanique dans le Midi de l’Espagne;’ that of the Bulgardagh (the principal group of the Cilician Taurus), from a list published by M. Pierre de Tchihatcheff in the ‘Bulletin of the French Botanical Society;’ that of Dalmatia, from Visiani’s excellent ‘Flora Dalmatica;’ and that of the southern slopes of the chain of the Alps from Nice to the Karst, formed by myself from all available sources.

In the same table I have introduced, for the purpose of further comparison, separate columns for the middle and superior regions of the Great Atlas valleys, and in connection with the last I have added in a separate column the results for the higher zone of the Sierra Nevada. Under each heading I have stated

Table. I—Showing the number of species of each of the principal groups and natural orders of plants in two valleys of the Great Atlas compared with other mountain districts in the Mediterranean region.

	Gt. Atlas valleys. 455 sp.		Middle Zone, Gt. Atlas. 341 sp.		Superior Zone, Gt. Atlas. 176 sp.		Sierra Nevada, &c., above 800 m. 890 sp.		Superior[1] Zone, Sierra Nevada. 486 sp.		Bulgardagh. 882 sp.		Dalmatia. 2,002 sp.		Southern side of the Alps. 2,545 sp.
Dicotyledones	391	86·0	286	83·9	154	87·5	762	85·6	419	86·2	808	91·6	1594	79·6	2035	80·0
Monocotyledones	64	14·0	55	16·1	22	12·5	128	14·4	67	13·8	74	8·4	408	20·4	510	20·0
Compositæ	63	13·8	46	13·5	22	12·5	119	13·4	63	13·0	97	11·0	235	11·7	343	13·5
Leguminosæ	48	10·5	38	11·1	14	8·0	67	7·5	32	6·6	93	10·5	222	11·1	172	6·8
Gramineæ	39	8·6	37	10·8	14	8·0	59	6·6	37	7·6	38	4·3	173	8·6	176	6·9
Caryophylleæ	26	5·7	14	4·1	15	8·5	40	4·5	29	6·0	81	9·2	74	3·7	121	4·8
Cruciferæ	25	5·5	7	2·1	21	11·9	49	5·5	37	7·6	84	9·5	98	4·9	139	5·5
Labiatæ	23	5·0	18	5·3	11	6·3	54	6·1	28	5·8	67	7·0	100	5·0	89	3·5
Scrophularineæ	21	4·6	13	3·8	10	5·7	37	4·2	28	5·8	39	4·4	66	3·3	109	4·3
Umbelliferæ	20	4·4	16	4·7	5	2·8	50	5·6	23	4·7	33	3·7	113	5·6	113	4·4
Rubiaceaæ	18	4·0	15	4·4	7	4·0	20	2·2	12	2·5	19	2·2	26	1·3	34	1·3
Papaveraceæ	10	2·2	8	2·3	3	1·7	10	1·1	6	1·2	12	1·4	14	0·7	14	0·6
Geraniaceaæ	10	2·2	8	2·3	4	2·3	10	1·1	6	1·2	6	0·7	17	0·8	23	0·9
Liliaceæ	10	2·2	6	1·8	4	2·3	15	1·7	9	1·9	23	2·6	61	3·0	52	2·0
Boragineæ	9	2·0	5	1·5	6	3·4	18	2·0	11	2·3	23	2·6	40	2·0	39	1·5
Ranunculaceæ	8	1·8	5	1·5	4	2·3	28	3·1	15	3·1	11	1·2	53	2·6	87	3·4
Cistineæ	7	1·5	6	1·8	1	0·6	23	2·6	10	2·1	1	0·1	11	0·5	10	0·4
Rosaceæ	7	1·5	4	1·2	3	1·7	26	2·6	20	4·1	21	2·4	57	2·8	93	3·7
Campanulaceæ	6	1·3	5	1·5	1	0·6	9	1·0	6	1·2	21	2·4	26	1·3	46	1·8
Convolvulaceæ	5	1·1	5	1·5	1	0·6	3	0·3	2	0·1	4	0·5	10	0·5	9	0·4
Coniferæ	5	1·1	4	1·2	1	0·6	10	1·1	8	1·6	15	1·7	15	0·7	11	0·4
Saxifrageæ (inclusive of Grossulariæ)	4	0·9	4	1·2	4	2·3	12	1·3	9	1·9	2	0·2	9	0·4	52	2·0
Cyperaceæ	4	0·9	4	1·2	1	0·6	17	1·9	12	2·5	7	0·8	43	2·2	119	4·7
Gentianeæ	0	0	0	0	0	0	7	0·8	5	1·0	4	0·5	14	0·07	31	1·2
Primulaceæ	2	0·4	2	0·6	1	0·6	7	0·8	6	1·2	8	0·9	12	0·6	60	2·4
Junceæ	1	0·2	1	0·3	0	0	11	1·2	9	1·9	0	0	8	0·4	31	1·2

the whole number of phanerogamous species included in the Flora of the region, and opposite the name of each natural order I have entered the number of species found in each region, and the percentage proportion which this number bears to the entire flora. Besides the orders which bear the largest proportion in the Great Atlas Flora I have enumerated those that usually characterise the vegetation of high mountains in this part of the world, though several of these are little, or not at all, represented in the Flora of the Great Atlas.

Confining the comparison in the first instance to the figures given for the Atlas Flora as a whole in the first column, and those given in the fourth, sixth, seventh, and eighth columns respectively, for the Sierra Nevada, the Bulgardagh, Dalmatia, and the southern side of the Alps, we remark in the first place that Monocotyledons bear about the same proportion to Dicotyledons in the Great Atlas that they do in the Sierra Nevada, the percentage here being much larger than it is in the Bulgardagh, and considerably less than in Dalmatia or the Southern Alps. In this part of the world this percentage in the Flora of a given region mainly depends upon the number of Gramineæ and Cyperaceæ. The abundance of the latter group in the Alps doubtless arises from the fact that at a former period physical conditions favoured the migration of a large number of northern species that have been unable to extend to the more southern mountain regions of the Mediterranean area.

In all the regions under consideration we find, with a single exception, that the same eight natural orders take precedence of all others as regards the number of species that they exhibit, the aggregate in every case exceeding one-half of the whole phanerogamous Flora. These natural orders are Compositæ, Leguminosæ, Gramineæ, Caryophylleæ, Cruciferæ, Labiatæ, Scrophularineæ, and Umbelliferæ. The exception arises from the prevalence, already noticed, of Cyperaceceæ in the Flora of the Southern Alps. In comparing the figures in the Great Atlas column with those for the other areas above enumerated, it is well to recollect that our materials are taken from a district much more limited in extent than the others, and are necessarily imperfect, because obtained from a single short visit to each valley at a season when many species are yet undeveloped. It is probable, for instance, that the proportion of Umbelliferæ would be increased if the whole Flora were better known. Subject to this remark, it will be seen, as might be expected, that the constituents of the Great Atlas Flora show more analogy with those of the Sierra Nevada and Bulgardagh Floras than with those of Dalmatia and the Southern Alps; but the proportion of Compositæ is larger than in any of them (nearly 14 per cent). In comparing the vegetation of a small district with that of a large one it must be recollected that a small natural group containing a few widely spread species, such as Geraniaceæ, is likely to show a larger percentage proportion to the whole Flora in the small district than in the larger one. It may happen that the same species are spread through both regions; but in one case the number is to be compared with a small total, in the other with a much larger one. This remark has a bearing on the fact that in the Great Atlas Flora the natural orders that bear an unusually large proportion to the total number of the Flora are Leguminosæ, Caryophylleæ, Rubiaceceæ, Papaveraceæ, Geraniaceæ, and Convolvulaceæ. On the other hand, there is a remarkable deficiency in the natural orders that especially characterise the Flora of the Alps, and in a less degree, the high mountains of Southern Europe. These are Ranunculaceceæ, Rosaceæ, Saxifrageæ, Primulaceæ, Junceæ, and Cyperaceæ; not to speak of Gentianeæ, which are here altogether absent.

If, instead of regarding the Atlas Flora as a whole, we examine separately the figures given in the several columns for the middle and superior zones respectively, we find very different proportions for the chief natural orders, except for Compositæ and Leguminosæ which are in both very numerous. In the middle region of the Atlas these two orders represent very nearly one-fourth of the phænogamous Flora. After these Gramineæ, Rubiaceæ, Papaveraceæ, Geraniaceæ, Cistineæ, and Convolvulaceæ are, in the middle region, unusually frequent, while Cruciferæ, Rosaceæ, Boragineæ, and Liliaceæ are remarkably deficient. In the superior zone, on the other hand, the proportion of Compositæ and Leguminosæ is less excessive, making jointly a little over one-fifth of the whole Flora of the upper region. The most marked characteristic here is the very large proportion of Cruciferæ, being less by one species only than the number of Compositæ. Taking into account the number of individuals as well as that of species, this must be regarded as the dominant element in the Flora of the higher region of the Great Atlas, affording as it does 12 per cent of the whole Flora. The only region in which this characteristic is approached is the Bulgardagh in Cilicia, where Cruciferæ supply near one-tenth of the whole list. Caryophylleæ also form an unusually large element in the Flora of the upper zone of the Atlas; but, unlike Cruciferæ, this order exhibits no endemic species, and four-fifths of the whole number are common plants of Central and Northern Europe. Rubiaceæ and Boragineæ have more representative species than is usual in mountain Floras; while there are but three species of Rosaceæ in our list; and Campanulaceæ, Primulaceæ, Coniferæ, and Cyperaceæ are each represented by a single species, and Gentianeæ and Junceæ are altogether absent from the higher zone.

Although statistical results, such as those given above, are not without interest, as throwing light upon the general characteristics of the Flora of a given region, any rational grounds for speculation as to the real affinities and past history of the vegetation must be derived from a closer examination of the individual species of which it is constituted. It is at least conceivable that two Floras should exhibit similar proportions of species belonging to the several natural groups, with no identical species, and with little or no indication of community of origin. The particulars given in our general list will have already led the reader to infer that the results of an examination into the distribution of the individual species that go to make up the Great Atlas exhibit some very peculiar features. Taking the totals at the foot of our list, and excluding cryptogams, it is seen that more than one-third of the species are plants of Middle and Northern Europe, while about one-sixth is made up of endemic species peculiar to Marocco, and, with few exceptions, not known out of the Great Atlas, more than half of the whole list belonging to one or other of these categories. The results, as shown in the following table, are still more remarkable when we separately examine the zones into which mountain vegetation is naturally divided. As in the former table the figures first entered in each column represent the number of species belonging to each category, those next given showing the percentage proportion borne by that number to the total proportion of each region.

Table II.—Showing the distribution of the species of flowering plants included in the Flora of the Great Atlas, and of the Sierra Nevada of Granada,[2] and the Bulgardagh in Cilicia.[3]

	Mid-European		Wide-spread Mediterranean		Confined to adjoining regions		Endemic
Great Atlas, including all species found above 1,200 m. 455 sp.	154	33·8	165	36·2	61	13·4	75	16·6
Middle Zone of Atlas, from 1,200 m. to 2,000 m. 341 sp.	106	31·1	141	41·3	46	13·5	48	14·1
Superior Zone of Atlas, from 2,000 m. to 3,500 m. 176 sp.	78	44·3	43	24·4	20	11·4	35	19·9
Superior Zone of Sierra Nevada, above 1,600 m. 486 sp.	209	43·0	74	15·2	104	21·4	99	20·4
Bulgardagh in Cilicia. 882 sp.	159	18·0	359	40·7	157	17·8	207	23·5

From this table we see that while over one-third of the whole Atlas Flora consists of plants of Central and Northern Europe, the proportion reaches nearly to one-half in the higher region (above 2,000 metres); and also that the proportion of endemic species, which in the aggregate is one-sixth of the whole, rises to one-fifth in the upper zone. On the other hand, the proportion of purely Mediterranean species, which amounts to 55 per cent. in the Flora of the middle zone, falls below 36 per cent. in the upper region. Of these Mediterranean species the large majority (more than two-thirds) are widely distributed plants, several of them extending to the mountains of Asia Minor, and twenty species only are exclusively confined to the Great Atlas and to the mountains of Southern Spain, the Lesser Atlas, or the Pyrenees. There is nothing in the distribution of these latter plants to indicate any special connection between the Atlas and any one of the mountain regions above mentioned. Six Atlas species are common to Southern Spain and the Algerian Atlas, six more are known only on the mountains of Southern Spain, five have been hitherto supposed to be peculiar to the Lesser Atlas, and three are elsewhere confined to the Pyrenees.

Some further light may be thrown on the origin of the Great Atlas Flora by considering the affinities of the plants which are reckoned in our list as endemic in Marocco, nearly all being confined, so far as we know, to the chain of the Great Atlas. Although all of these, along with some that we have classed as mere varieties, would be counted as distinct species by many botanists, a considerable number, amounting to more than a quarter of the whole, are, according to the views expressed elsewhere by the writer,[4] to be ranked as sub-species. But here again we fail to discover indications of special relations between the Great Atlas Flora and that of neighbouring mountain regions. Ranking as sub-species twenty-one out of the seventy-five endemic forms enumerated in our list, we find that ten of these are allied to widely spread Mediterranean species, three are related to plants of Central Europe, three to species common to Algeria and Southern Spain, three more to species confined to the Spanish peninsula, and two to endemic Algerian forms.

If we scrutinise in the same manner the endemic forms of the higher region of the Great Atlas, we find that out of the thirty-five enumerated eight, or less than one-fourth, are to be ranked as sub-species. Of these, three are nearly allied to wide-spread Mediterranean species, one to a plant common to Spain and Algeria, two to endemic Spanish species, one to an Algerian endemic form, and one is related to a species indigenous in the Alps and other high mountains of Central Europe.

While recognising the fact that the relations between the vegetable population of the Great Atlas and that of the south of Spain are less close than might have been expected on theoretical grounds, we must yet admit that, on the whole, the Great Atlas is more nearly connected in a botanical sense with this than with any other mountain region that is known to us; and it becomes a matter of some interest to compare closely the list of species obtained by us in the Atlas, with the comparatively well known Flora of Southern Spain. The results of this comparison are given for the Great Atlas generally, and for the superior zone separately, in the following table, in which the Atlas species are distinguished under five heads: 1, those found in the higher region of the Sierra Nevada; 2, in the mountain region of Andalusia; 3, in the lower warm region below the level of about 2,000 feet; 4, absent from Southern Spain, but found in the central or northern provinces; and 5, those not included in the Spanish Flora.

Table III.

	Superior region, Sierra Nevada	Mountain region of Andalusia	Lower region of Southern Spain	Central, or Northern Spain, exclusively	Absent from Spain
Great Atlas Valleys. 455 sp.	103	82	100	44	126
Superior region of the Great Atlas. 176 sp.	61	19	20	21	55

The figures given in this table are of much interest, proving, as they do, the wide differences that exist between the Floras of two mountain regions not widely separated from each other, and exposed to climatal conditions not altogether dissimilar. We see that three-sevenths of the plants found in the higher region of the Great Atlas are absent from the South of Spain, and that the same remark applies to considerably more than one-third of all the plants found in the portion of the Great Atlas visited by us, although a notable proportion (in both cases) is to be found in Central and Northern Spain. Especially noteworthy is the fact that many of the species thus absent in Southern Spain are plants of Central Europe, most of which extend to the northern part of the Spanish Peninsula, although some of them are altogether wanting in the Floras of Spain and Portugal.

A simple inspection of our list suffices to show that it discloses no trace of affinity between the Great Atlas Flora and that of the Canary Islands, or, to use a term of wider geographical import, that of Macaronesia. The few species belonging exclusively to the latter region and to Marocco are nearly all confined to the coast region.[5] Almost all the species common to the Atlas and to Macaronesia are widely spread Mediterranean plants that ascend from the low country into the valleys. The solitary mountain plant belonging to this category is Arabis albida, the southern form of A. alpina, common in the East, and in the Apennines of Central and Southern Italy, but which, strange to say, has not been found in Spain. In Teneriffe, as in the Atlas, it ascends to about the level of 2,700 metres above the sea. The only fact suggesting a remote affinity between the Great Atlas and Macaronesian Floras is the presence in the former of a species of Monanthes, a generic group hitherto found only in the Canary and Cape de Verde Islands. But the absence of any closer connection clearly shows that the separation between the Macaronesian group and the main land of Africa must date from a period, even geologically speaking, remote.

When we come to sum up the results of the foregoing discussion, bearing always in mind the fact that we possess a mere fragment of the Flora of the Great Atlas, and that future exploration may largely modify our conclusions, we find as its most striking characteristic the presence of a large proportion of plants of Central and Northern Europe, along with a considerable number of peculiar species not hitherto known elsewhere; and we observe that these two constituents, which together form about one-half of the Flora of the region here discussed, amount to very nearly two-thirds of the species found in the higher zone. We remark that of these northern plants none are of Alpine or Arctic type, that nearly all belong to what has been called the Germanic Flora, and all are plants of the plain, not in Europe characteristic of mountain vegetation.[6]

Of the species belonging to the Mediterranean region, which constitute more than one-half of the vegetation of the middle zone, and about one-third of that of the higher zone of the Atlas, the large majority are widely diffused species. The remaining number, for the most part mountain plants, may be divided into three nearly equal sections, some being common both to Southern Spain and Algeria, others to the Atlas and Southern Spain exclusively, and others to the Great Atlas and the Lesser Atlas of Algeria. Nothing indicates any special connection with the Floras of either of those regions.

The absence of any distinct generic types from the Great Atlas Flora has already been remarked. It is not less important to note the absence of any of the southern types, characteristic of the sub-tropical zone, some representatives of which are found in the same or even in higher latitudes, in Arabia, Syria, Persia, and Northern India, and which also appear in the Canary Islands. We finally are led to regard the mountain Flora of Marocco as a southern extension of the European temperate Flora, with little or no admixture of extraneous elements, but so long isolated from the neighbouring regions, that a considerable number of new specific types have here been developed. The physical causes which have operated to bring about these conditions are doubtless numerous and complicated, but the most important of them are easily indicated. The influence of the Atlantic climate, and the prevailing direction of the aërial and oceanic currents, have fitted this region for the habitation of such northern species as do not require a long period of winter repose. In the present condition of the African continent, the Great Desert, extending for a distance of 700 or 800 miles between the Atlas and the river region of tropical Africa, effectually prevents the northward extension of most forms of animal and vegetable life; while in a period geologically recent, it is most probable that the same area was occupied by a wide gulf, which served the same purpose of barring the migration of southern forms.

It may be premature to attempt to trace in further detail the origin of the Great Atlas Flora; but the facts already ascertained certainly authorise some negative inferences. The absence of plants of Arctic type proves that if some mountains of Southern Europe received contributions to their vegetation during the glacial period by means of floating ice-rafts, that mode of diffusion did not extend to the Great Atlas. If we suppose that during the glacial period the temperature of the region north of the Atlas had fallen so low as to permit the migration of northern species across the intervening low country, we find it difficult to understand why so many species which, according to this theory, must have retreated to the Atlas on the subsequent rise of temperature, should have failed also to find a refuge in the mountains of Southern Spain.

It is a further difficulty that if the constituents of the Great Atlas Flora had, to a large extent, travelled by the route here indicated, other species, now inhabiting the mountains of Southern Spain, could scarcely fail to take the same road, and a much nearer connection than is now apparent would have been established between the Floras of these two mountain regions.

It is, at least, possible that the wide diffusion of many of the species constituting the so-called Germanic Flora may date from a period much more remote than is ordinarily supposed; and it is a circumstance not without significance that so many species of this type prove themselves capable of tolerating wide variations in conditions of soil and climate.

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APPENDIX H.

Notes on the Geology of the Plain of Marocco and the Great Atlas.

By George Maw, F.G.S., F.L.S., &c.

Of the Geology of Barbary little information has hitherto been put on record. The only publications with which I am acquainted are some notes on the geological features of the district between Tangier and Marocco in Lieut. Washington’s ‘Geographical Notice of the Empire of Marocco,’ published in the first volume of the ‘Journal of the Royal Geographical Society;’ a few cursory remarks on the Marocco Plain by Dr. Hodgkin, in his account of Sir Moses Montefiore’s ‘Mission to Morocco in 1864;’ a short paper, by Mr. G. B. Stacey, on the subsidence of the coast near Benghazi, published in the twenty-third volume of the ‘Quarterly Journal of the Geological Society;’ a report by M. Mourlon on some rocks and fossils in the Museum of Brussels, collected in the north-west of Marocco by M. Desquin, a Belgian engineer, published in Vol. XXX. of the ‘Bulletin de l’Académie Royale de Belgique,’ for 1870, to which I shall have further occasion to refer; a geological memoir, by M. Coquand (‘Bull. de la Soc. Géolog. de France,’ vol. iv. p. 1188), on the environs of Tangier and northern part of Marocco; and finally, a paper I read before the Geological Society of London in 1872.

Barbary, with the exception of the immediate neighbourhood of a few of the ports, has been almost inaccessible to Europeans; and the extreme jealousy of the Moorish Government with reference to the mineral riches of the country has hitherto prevented any geological investigation. In the year 1869 I visited the northern portion of Marocco, including the Tangier and Tetuan promontory, and during the spring of 1871 accompanied Dr. Hooker and Mr. Ball to Mogador, the city of Marocco and the Great Atlas, permission for our visit having been obtained from the late Sultan through representations made to the Moorish Government by Lord Granville through Sir John D. Hay, our Minister Plenipotentiary at Tangier.

The object of the second journey was mainly botanical; and as an engagement was given by Dr. Hooker that we should not collect minerals, the opportunities for geological investigation were very limited.

The observations I was able to make on the structure of the great chain, which had not been previously ascended by a European, and of the plain of Marocco, are embodied in the accompanying section. Stopping for about a fortnight at Tangier, we made several excursions in the neighbourhood. The western part of the northern promontory of Marocco, facing the Straits of Gibraltar, consists of highly-contorted beds of hard courses interstratified with brindled yellowish sandstones and variegated puce and grey marls, having a general dip to the south-east, but so twisted about that the dip and strike are often reversed within a few feet. The country has a general undulating contour, here and there rising up into ridges of from 2,000 to 3,000 feet, in which the hard bands weathered out from the softer strata are strikingly prominent from a great distance.

We observed no palæontological evidence of their age; but, judging from their resemblance to the cliff-sections near Saffi, where fossils occur, they are presumably Neocomian or Cretaceous.

Fucoids were collected by M. Coquand in the vicinity of Tangier, in beds considered by him to be representatives of the Upper Chalk; but M. Mourlon, referring to the works of Pareto and Studer on the nummulitic rocks of the Northern Apennines and Switzerland, inclines to place the Tangier fucoid beds above the nummulitic horizon, and as part of the Upper Eocene. But near the villages of Souani and Meharain, a little to the south of Tangier, undoubted Cretaceous fossils were met with by M. Desquin, including