362 



General Biology 



THE MUSCULAR SYSTEM 



As in the crayfish, the muscles of the honey bee are attached to the 

 inner walls of the body. The number of muscles is very large. The 

 largest muscles are those which move the wings and legs. 



Muscles are both voluntary and involuntary. A good example of 

 the latter has already been noted in the experiment suggested of placing 

 a portion of the intestine in a one-half of one per cent salt solution when 



the lips of the stomach-mouth will open 

 and close for some time. 



Insects usually have much greater 

 muscular strength proportionately than 

 larger animals. This is accounted for by 

 the fact that the weight of muscle in- 

 creases as the cube of its diameter, while 

 its strength increases only as the square 

 of its diameter. 



THE REPRODUCTIVE SYSTEM 



Only the queen (Fig. 236, A) can lay 

 eggs, although the workers have rudi- 

 mentary ovaries. 



The two- ovaries almost fill the ab- 

 domen of the queen. Each of the ovaries 

 is made up of a great number of ovarian 

 tubules which contain eggs of different 

 sizes. The eggs pass into the oviduct 

 from the tubules, thence into the vagina 

 and out of the body through the genital 

 aperture. 



There is an opening into the vagina 

 which connects with the spermatheca, or 

 sac, in which the sperm are stored, and 

 sperm from this sac may apparently be 

 released at will by the queen as the eggs 

 pass through. If the sperm is not re- 

 leased, the egg is not fertilized and then 

 drones hatch. Only females hatch from 

 fertilized eggs. 



In the drone (Fig. 236, B) there are 

 two testes made up of several hundred 

 spermatic tubules in which the sperm are 

 formed. A pair of fine tubes, called vasa 

 deferentia, connect these spermatic tubes 

 with the seminal vesicles. These latter 



Fig. 236. 



A. Reproductive organs, sting, and 

 poison gland of queen honey-bee. AGL, 

 acid gland; AG ID., duct of acid gland; 

 BGL, alkaline gland; Ov., ovary; ov., 

 ovarian tubules; OvD., oviduct; Psn.- 

 Sc, poison sac; Spm., spermatheca; 

 Stn., sting; StnPlp., sting feeler; Vag., 

 vagina. 



B. Reproductive organs of drone 

 bee, dorsal view, natural position. 

 AcGl., accessory gland; B., bulb of 

 penis; EjD., ejaculatory duct; Pen, 

 penis; Tes., testis; vDef., vas deferens; 

 Ves., seminal vesicle; tt., un., yy., zz., 

 parts of penis. (From Snodgrass, 

 Tech. Series, 18, Bur. Ent., U. S. 

 Dep't of Agric.) 



