DIARRHEA AND DYSENTERY.

In the chapter on wintering bees allusion has been made to certain conditions which bring about diarrhea in bees. Not only will soured or fermented honey produce this disease, but thin honey also, by requiring too great exertion on the part of the bees to get rid of the surplus moisture taken into their bodies, may indirectly cause the disease. Repeated complaints have been made by those located near cider mills that the apple juice collected by their bees was the cause of diarrhea and dysentery. Aphidid secretions sometimes have the same effect. Prolonged and intense cold in the interior of the hive, especially if the stores are not of the best quality, causes distention and resulting weakness and soiling of the hive and combs. Dampness and chilling of individual bees frequently cause it. The effort some make to avoid the dampness often results in the chilling, for the cover is removed, and also some portion of the packing or the quilt or honey board to let the air pass through to dry the interior. The true remedy is a cleansing flight and warmth in the hive. Should the weather not be favorable for this out of doors, the hive may be brought into a warm room and a cage of wire cloth 2 or 3 feet square placed over the entrance. When thoroughly warmed up the bees will fly in this and find their way back into the hive. It is best to leave them in the warm room two or three days, lowering the temperature gradually before returning the hive to its outside stand.

FOUL BROOD.

This disease, being highly contagious, is dreaded most of all by the bee keeper. It is due to the presence of minute vegetable organisms in the body of the bee, the larva, or the egg, which prey upon its tissues. These, as Prof. Frank Cheshire has shown, are bacilli, which, multiplying with marvelous rapidity by division and also by spores, are carried from hive to hive, until from a single infection the whole apiary is soon ruined. The particular bacillus which is commonly known as foul brood Professor Cheshire has described as Bacillus alvei, or hive bacillus, as it affects not only the brood but also the adult bees. (See Pl. XI.) The first symptoms noticeable in the hive are its lack of energy, then dead larvæ turned black in the cells, and finally sunken caps, some of them perforated slightly over larvæ and pupæ.

All of these symptoms may, however, be present when no foul brood exists; but if, upon opening some of the cells whose caps are sunken or slightly punctured, a brown, ropy, putrid mass is found, which, when lifted on the end of a sliver of wood, glides back into the cell or strings down from the mass like thick sirup, it is pretty certain that foul brood is present. Caution is necessary or it maybe spread all through the apiary. The hands, as well as all tools used about the infected colony, should be cleansed by washing in a solution of corrosive sublimate (one-eighth ounce dissolved in 1 gallon water) before going to another hive. If but few are found diseased they should be burned at once—at night, when all the bees are at home. If all or nearly all are affected, or if the disease does not seem virulent and other apiaries in the neighborhood are not endangered thereby, a cure may be attempted. Removal of all of the combs and confinement of the bees in an empty box, obliging them to fast until some drop from hunger, followed after releasing them by liberal feeding, will frequently effect a cure, as indicated many years since by Mr. M. Quinby. The hives may be disinfected by washing in carbolic-acid water and used again. A second removal of the bees and fasting may be necessary in some cases. It will also be well to feed medicated sirup—1 part of carbolic acid, or phenol, to 600 or 700 parts of sirup. Many omit the fasting, but destroy all combs and frames and supply comb-foundation starters, removing four days later all combs built and giving a second lot of starters. It is well to supplement this treatment with feeding of medicated sirup. Phenol having been suggested to Professor Cheshire as a remedy, he experimented until he found that if a sirup containing 1 part of phenol to 400 or 500 parts of the food be poured in the cells adjacent to the brood, and the diseased brood, after brushing off the bees, sprayed with a solution of 1 phenol to 50 water, a cure was speedily effected. The great risk of spreading the disease, as well as the time and expense which a cure by drugs by the fasting process involves, will cause immediate destruction to be resorted to as the cheapest in the end if taken in time.

Bacillus gaytoni, also described by Professor Cheshire, is characterized by loss of hairy covering on the part of the workers and their crawling out of the hives over the ground, constantly wriggling their bodies until death occurs. It yields, according to Professor Cheshire, to the same remedies as Bacillus alvei, but having been less destructive and being far more likely to disappear without effort to cure it, less attention has been given to it. Lately, however, it has been alarmingly destructive in some of the extensive apiaries of California. Colorado, and Texas, so that some simple remedy would be very welcome.

THE WAX OR BEE MOTH.

The larva of a moth known to entomologists as Galleria mellonella Linn. gnaws passages through the combs of the bees, especially those in or near the brood nest, often proving very destructive in weak or neglected colonies. The popular name, wax moth, was doubtless given on the supposition that the food of the larva was chiefly wax; but when an attempt to rear them on this substance in its usual commercial purity is made slight development only results. Probably chemically pure wax would not be touched by the larva; but in combs containing the larval skins left by developing bees, or containing brood or pollen, they reach their highest development if left undisturbed during warm weather, finding ample nourishment in the nitrogen-containing pollen and animal tissues left by the molting larvæ. To protect themselves from the bees they line their galleries through the combs with a strong web of silk and are able to retreat or advance rapidly through them when attacked. The observing bee keeper will occasionally notice the moths resting during the daytime on the corners of the hives or under the roof projections or edges of the bottom boards. Its color is dull or ashy gray, with light and dark streaks, making it so nearly like a protruding sliver of a weather-beaten board as to protect it materially from its enemies when resting on any unpainted surface that has been long exposed. At nightfall the moths may be seen flitting about the hive entrances, seeking an opportunity to enter and deposit their eggs. If prevented by the bees, which are then instinctively on the alert, they deposit in the crevices between the hive and stand or between the hive and cap. The minute larvæ as they emerge soon make their way into the interior of the hive. It is possible also that some of the eggs of the moth may be left where the bees crawling over them carry them into the hive by accident, the freshly laid egg adhering readily to any substance it touches. In the northern and middle sections of the United States two broods are reared, the first appearing in May, the second and larger brood in midsummer or even August. The eggs deposited by the last brood develop slowly in the cooler autumn weather, but usually reach the pupal stage, in which they normally pass the winter. Individual moths may, however, be seen about the apiary during June and July, and even into the autumn, so that egg deposition is constantly going on, and any combs removed from the hive and left unprotected by bees, especially if in a warm apartment or a closed box, will soon be in complete possession of the destructive larvæ, which wax fat and soon reduce them to a mass of webs. The only remedies are to keep the combs under the constant protection of the bees, or, if the colonies are not populous enough to cover them fairly, the combs should be hung so as to leave a space between them in a cupboard or large box which can be closed tightly, so as to subject them for some time to the fumes generated by throwing a handful or two of sulphur on live coals, or to the odors of bisulphide of carbon in an open vial. Caution is needed in the use of the latter, since it is highly inflammable.

Oriental races of bees are more energetic than others in clearing out wax-moth larvæ, and Carniolans and Italians more so than the common bees. But in colonies always supplied with good queens the wax-moth larvæ make little headway, and it is therefore only the neglected hives that are seriously troubled. Moth-trap attachments or moth-proof hives are therefore of no use, unless, in the case of the former, larvæ seeking a secure place in which to pupate may be caught; but that implies frequent examination, and the same or less attention to the colony itself will suffice to do away with almost any breeding of moths. Hives proof against the entrance of wax-moth larvæ would, as the statements here made regarding the breeding habits of the moth indicate, exclude the bees also. From the foregoing it can be readily seen that the attentive apiarist no longer regards the wax moth as a serious pest.

BRAULA OR "BEE LOUSE."

A wingless dipteron, Braula cæca Nitsch, known under the common name of "bee louse," is a troublesome parasite on bees in Mediterranean countries, the adults, which are very large in proportion to the host, gathering on the thoraces of the workers, rarely of the drones, but in great numbers on the queens. The writer has removed seventy-five at one time from a queen, though ordinarily the numbers do not exceed a dozen. When numerous they render the queen weak by the removal of vital fluids. The insect has frequently been imported to this country on queens with attendant bees, but thus far has probably gained no foothold. Likely it will never do so in the North, but the case might be different in any region resembling southern Europe in climate, and it is by all means advisable to remove every one from any queen or worker arriving here infested with them.

OTHER ENEMIES.

Robber flies, dragon flies, etc.—Several species of Asilus and related predaceous Diptera do not live upon injurious insects alone, but also capture and devour honey bees. They are more destructive in the South than elsewhere. The same is true of the neuropterous insects known as mosquito hawks, dragon flies, or devil's darning needles. There seems to be no remedy for any of these except that of frightening them away when noticed about the apiary. The "stinging bugs," belonging in the hemipterous family Phymatidæ, often capture and destroy workers as they visit the flowers. No remedy is practicable.

Ants and wasps.—Some of the larger ants and social wasps are very troublesome to the apiarist in tropical and even in subtropical regions. They seize the workers and cut them in pieces with their powerful jaws. Having once reduced the hive defenders, they even make bold to enter and carry off the queen as well as help themselves to honey. Trapping them with honey or with meat and killing them, as well as destroying the nests when found, are the only remedies. The paper nests are easily burned away, while an effectual remedy against ants is to open the hill and pour in an ounce or two of bisulphide of carbon.

Spiders.—Webs made about hive entrances often capture bees as well as wax moths, and, notwithstanding this last-mentioned point in their favor, they had better be removed.

Toads and lizards.—These devour many bees, and whenever found near the hives should be destroyed or removed to the vegetable garden.

Birds.—Swallows and kingbirds have been accused of eating many bees. It is probable that the destruction of injurious insects by them more than makes amends for the bees taken. This was clearly proven in the case of the kingbird, stomachs of which, examined at the United States Department of Agriculture, showed only a very small percentage of honey bees, and these mostly drones.

MAMMALS.

Mice gaining access to the hive during winter gnaw out among the combs a nest cavity and eat honey, pollen, and bees. Low entrances, covered, if found necessary, with a strip of tin, will prevent the mice from gnawing larger holes, yet permit the bees to pass in and out. Skunks sometimes disturb hive entrances and catch bees as they come out. This is particularly vexatious in the winter, when colonies should be left quiet. In mountain localities, bears, led by their fondness for honey, still occasionally overturn beehives. The remedies for both of these are, of course, shooting or trapping.

ROBBER BEES.

When forage is scarce in the field, bees belonging to different colonies often wage fierce wars over the stores already in hives. Thousands are killed and the victors relentlessly carry off as booty every drop of honey from the vanquished hive, leaving its bees to starve miserably. A great stir and loud buzzing in the hive of the conquerors attests their rejoicing over the ill-gotten gains. Nor have they any code of morals which inclines them to select as opponents forces equal in strength to their own. With them "all's fair in war." Their only object is plunder, and they therefore select the most defenseless, a colony disorganized through loss of its queen being an especial mark for a combined attack.

Extreme caution to prevent robbing is always advisable. A little carelessness or neglect in the apiary early in the spring or toward the latter part of the season may result in much loss. It is easier to prevent robbing than to check it at once or without loss after it is well under way. Leaving honey exposed about the apiary often induces robbers to begin their work; hence extracting and similar work must be done in bee-proof rooms whenever the bees are not gathering honey freely. It may at such times be necessary to do all manipulating early in the morning, before many of the bees have begun to fly, or later in the day, after they have ceased, or even under a tent made of mosquito netting and placed temporarily over the hive to be manipulated. Queenless and weak colonies should be put in order if possible before the honey flow ceases. In any event the entrances of such hives should be contracted until but few or even no more than one bee can gain access to the interior at one time. Professor Cheshire has devised an excellent entrance block to prevent or check robbing. This is shown in fig. 70, and is so simple that anyone can make it. When contracted and placed at the hive entrance it will be seen that the robbers must make their way through a narrow and bent passage, something they are loath to attempt, especially if at the first onset they find the passage well guarded.

If robbing has begun it may sometimes be stopped by throwing coarse grass or weeds over the entrance of the hive attacked, or by leaning a pane of glass against its front, the entrance being, of course, contracted as indicated above. These plans tend to confuse the robbers for a time, and meanwhile the rightful occupants of the hive may be able to organize for defense. If convenient the colony attacked may be moved a distance of a half mile or more and placed as far as possible from other apiaries until it can recuperate. Another plan in extreme cases is to put the colony in a dark cellar for a few days, confining the bees to the hive with wire cloth, so as to allow plenty of ventilation, as described under the head of "Moving bees." When brought out of the cellar it is well to place the colony on a new stand, apart from the other bees, contract the entrance, and lean a board against the front of the hive. It is also safest to bring it out late in the day, even just at dusk, so the bees will begin flying from it gradually and not attract the attention of robbers. It may be well, when removing a colony from its stand to save it from robbers, to put in its place a hive with combs containing a little honey and pollen. The robbers, instead of scattering and entering adjacent hives, will continue to visit the same stand, their numbers gradually diminishing as the honey gives out and the pollen is sucked dry. If meanwhile the entrances of adjoining hives have been contracted and these colonies are fairly strong and in normal condition, individual robbers will be successively repulsed as they appear. Quiet will thus be eventually restored.

LAYING WORKERS.

Although laying workers are not strictly enemies of their kind, their work hastens the extinction of the colony to which they belong, in case the latter has become queenless and is without the means of rearing another queen. They cause the expenditure of the stores and strength of the colonies in a vain though well-meant endeavor to perpetuate their species; the eggs which laying workers deposit, and for whose development through the larval stage much honey and pollen are required, only resulting in the production of a lot of drones, for the most part weak and dwarfed.

If not discovered until the hive is nearly depopulated, the remaining old bees should be brushed off, and the combs, after the sealed drone brood has been unmapped and jarred out, may be distributed among other colonies. Should the affected colony still be worth saving, combs containing emerging bees should be added and a queen introduced a few days later, or a queen cell inserted, as soon as the added brood has stocked the hive well with young bees.