Alefeld, Dr.—Vol. 5. Nos. 15 and 16. EichstÄdt 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.—BeitrÄge 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. EichstÄdt Bienen-Zeitung. 29 Jahrg. Nrs. 22 u. 23, pp. 258-270.