The pollen baskets are not loaded by the crossing over of one hind leg upon the other or to any great extent by the crossing of the middle legs over the corbiculae. The middle legs deposit their loads upon the pollen combs of the hind plantae, and the plantae, in turn, transfer the pollen of one leg to the pecten comb of the other, the pecten of one leg sc.r.a.ping downward over the pollen comb of the opposite leg. (See fig. 7.) A little pollen is loaded directly from the middle legs into the baskets when these legs are used to pat down the pollen ma.s.ses.

(See fig. 6.)

Aside from the foregoing exception, all of the pollen which reaches the baskets enters them from below, since it is first secured by the pecten combs, and is then pushed upward by the impact of the rising auricles, which squeeze it against the distal ends of the tibiae and force it on into the baskets to meet that which has gone before.

The long hairs which form the lateral boundaries of the baskets are not used to comb out pollen from the brushes of any of the legs. They serve to retain the acc.u.mulating ma.s.ses within the baskets and to support the weight of the pollen, as it projects far beyond the surfaces of the tibiae.

Pollen grains are moistened and rendered cohesive by the addition to them of fluid substances which come from the mouth. a.n.a.lyses show that honey forms a large part of this moistening fluid, although nectar and secretions from the salivary glands are probably present also.

In the process of pollen manipulation this fluid substance becomes well distributed over the brushes of all of the legs. The forelegs acquire moisture by brushing over the mouthparts, and they transfer this to the hairs of the breast and to the middle-leg brushes when they come in contact with them. The middle-leg brushes transmit their moisture to the pollen combs of the hind legs when they rub upon them.

All of these brushes also transport wet pollen which has come from the mouthparts and thereby acquire additional moisture. The auricles and the plantae of the hind legs become particularly wet from this source, since fluid is squeezed from the wet pollen when it is compressed between the auricles and the distal ends of the tibiae. Dry pollen which falls upon the body hairs becomes moist when brought into contact with the wet brushes or with wet pollen.

During the process of manipulation pollen pa.s.ses backward from its point of contact with the bee toward its resting place within the baskets.

Pollen which the collecting bee carries to the hive is deposited by this bee within one of the cells of the comb. As a rule, this pollen is securely packed in the cell by some other worker, which flattens out the rounded ma.s.ses and adds more fluid to them.

BIBLIOGRAPHY.

Alefeld, Dr.--Vol. 5. Nos. 15 and 16. Eichstadt Bienen Zeitung.

Summarized in "Die Bienenzeitung in neuer, geschichteter und systematische geordneter Ausgabe." Herausgegeben vom Schinid und Kleine: Erste Band, Theoretischer Theile. 1861.

Casteel, D. B., 1912.--The manipulation of the wax scales of the honey bee, Circular 161, Bureau of Entomology, U. S. Dept. Agriculture, pp. 15.

Cheshire, F. R., 1886.--Bees and bee-keeping; scientific and practical.

Vol. I, scientific; II, practical. London.

Fleischmann und Zander, 1910.--Beitrage zur Naturgeschichte der Honigbiene.

Franz, A., 1906.--In "Unsere Bienen," herausgegeben von Ludwig, A., Berlin, pp. [viii]+831.

Hommell, R., 1906.--Apiculture, Encyclopedic Agricola, Paris.

Phillips, E. F., 1905.--Structure and development of the compound eye of the bee. Proc. Acad. Nat. Sci. Philadelphia, vol. 57, pp. 123-157.

Sladen, F. W. L., 1911.--How pollen is collected by the social bees, and the part played in the process by the auricle. British Bee Journal, vol. 39, pp. 491-493, Dec. 14.

Sladen, F. W. L., 1912.--(_a_) How pollen is collected by the honey bee.

Nature, vol. 88, pp. 586, 587, Feb. 29.

1912.--(_b_) Further notes on how the corbicula is loaded with pollen.

British Bee Journal, vol. 40, pp. 144, 145, Apr. 11.

1912.--(_c_) Pollen collecting. British Bee Journal, vol. 40, pp. 164-166, Apr. 25.

1912.--(_d_) How propolis is collected. Some further notes on pollen-collecting. Gleanings in Bee Culture, vol. 40, pp. 335, 336, June 1.

1912.--(_e_) Hind legs of the worker honey bee. Canadian Bee Journal, vol. 20, p. 203. July.

Wolff, O. J. B., 1873.--Das Pollen-Einsammeln der Biene. Eichstadt Bienen-Zeitung. 29 Jahrg. Nrs. 22 u. 23, pp. 258-270.