ANATOMY OF THE BEE. 



509 



substances. This change is effected partly 

 by the inhaled oxygen combining witli the 

 waste products, resulting in the formation 

 of compounds of nitrogen which dissolve in 

 the blood, and of caibonic-acid gas which 

 diffuses into the tracheal tubes and is ex- 

 haled. The nitrogen compounds are sup- 

 posed to be removed by the Mulpighian 

 tubules (Fig. 6, Mai), which are regarded as 

 the kidneys of insects. 



The nervous system consists of a series of 

 small masses of nerve tissue called ganglia, 

 lying along the median ventral line of the 

 body cavity (Fig. 1, lGng-7Gng) , the two of 

 the thorax being much larger than those of 

 the abdomen. Each two are connected by a 

 pair of cords called commissures. Nerves are 

 given off from these ganglia to the various 

 organs and parts of the body, and to the legs 

 and wings. In the hpfd there are two gan- 



spermatozoa are stored during the adult 

 stage of the drone's life. The two vesicles 

 open into the bases of two enormous mucous 

 glands (AcOi) which come together in a nar- 

 row muhcular tube, the ejacululory duct 

 {EjD) . This opens into the anterior end of 

 the p(nis {Pen} . The last is a complicated 

 organ, shown at E, Fig. 7. It is ordinarily 

 contained within the cavity of the aljdomen; 

 but during copulation it is entirely everted, 

 and its basal pouches (zz) lock into corres- 

 ponding pouches of the oviduct of the queen. 

 The eggs are formed by the ovaries of the 

 female (Fig. 8, Ov) , each of which consists 

 of a thick mass of tubules called the ovari- 

 oles (ov) , within which the eggs grow from 

 simple cells at their upper ends into the 

 mature eggs found at their lower ends. The 

 ovarioles of each oviary open into an oviduct 

 (Oi-P) , wliich two unte into a widp median 



From Bulletin No. 16, "The Anatomy of the Honey-bee," by Snodgrass, Bureau of Ent., Kept, of Ag., Washington, D. C. 



FIG. 5.- Left Side Of Sting and Its accessory plates, with alkaline gland (BGD and base of poison-siic 

 (PsnSf) attached. BG?, alkaline-poieon glaid; Lcf. lancet; O/-, oblong plate: PsnSc, \)ase ot poison-sac 

 holding secretion from acid-planfl (see Fig. 8); Qd, quadrate nlate; IXS. median part ot nintn aDaominai 

 sternum; S7*^, arm of sheath; S/(b, bulb of sheath; S7(S, shaft of sheath; SfnP?p, palpus of sting, l)t, 

 tri'iiigular plate. 



glionic masses. One is called the brain 

 [OpL) , and is situated above the oesophagus, 

 where it gives off nerves to the eyes, the 

 antenuEe, the front, and the labrum. The 

 other called the suboesophageal ganyliem, lies 

 in the lower part of the head, and inner- 

 vates the mouth parts, while it is connected 

 by commissures with both the brain and the 

 first thoracic ganglion. 



The reproductive system consists of those 

 organs that produce the spermatozoa in the 

 male and the eggs in the female and their 

 accessory parts. 



The spermatozoa are formed in the testes 

 of the male (Fig. 7, A, Tcs) , a i^air of small 

 bodies in the front part of the abdomen, 

 said to be developed at their highest in the 

 pupal stage. Each is connected by a coiled 

 tube, the vas deferens (VBef), with a long 

 sac, the seminal vesicle ( Fes) in which the 



tube called the vaejina ( Vag) that swells pos- 

 teriorly into a large pouch known as the 

 bursa copulatrix (BCpx) , opening to the 

 exterior in the eighth segment beneath the 

 base of the sting. 



During copulation the drone ejects the 

 spermatozoa into the upper end of the 

 vagina of the queen. The spermatozoa con- 

 sist of minute vibratory threads (Fig. 7, C) , 

 which, probably, by their own motion, make 

 their way up through a small tube opening 

 into the dorsal wall of the vagina, and so 

 reach a globular sac (Fig. 7, Sjim) called the 

 spermathfca,. Here they are held during the 

 rest of the lifetime of the queen, to be ex- 

 truded in small bundles, of about a hundred 

 each, according to Breslaw, upon the eggs 

 passing out of the vagina. Thus are the fe- 

 male eggs fertilized, the drone eggs develop- 

 ing without the addition of the male elemeut. 



