60 Female Organs of Insects. 



to__the spermatheca of the female. ' Beside this latter organ 

 are the sheath, the claspers when present, and in the male bee 

 those large yellow glandular sacks (Fig. 12, i), which are often 

 seen to dart forth as the drone is held in the warm hand. 



The female organs (Fig. 13) consist of the ovaries (Fig. 13, 

 a, a), which are situated one on either side of the abdominal 

 cavity. From these extend the two oviducts (Fig. 13, 'b), 

 which unite into the common oviduct (Fig. 13, c) through 

 which the eggs pass in deposition. In many insects - there is 

 beside this oviduct, and connected with it, a sack (Fig. 13, e) 

 called the spermatheca, which receives the male fluid in copu- 

 lation, and which, by extruding its contents, must ever after 

 do the work of impregnation. 



This sack was discovered and its use suggested by Malpighi 

 as early as 1686, but its function was not fully demonstrated 

 till 1792, when the great anatomist, John Hunter, showed 

 that in copulation this was filled. The ovaries are multitu.- 

 bular organs. In some insects, as fertile work ers, there are 

 but very few tubes — two or three ; while in the queen bee there 

 are more than one hundred . In these tubes the ova or eggs grow, 

 as do the sperm cells in the vesicles of the testes. The number of 

 eggs is variable. Some insects, as the mud-wasps, produce very 

 few, while the queen white-ant extrudes millions. The end of 

 the oviduct, called the ovipositor, is wonderful in its variation. 

 Sometimes it consists of concentric rings, like a spy-glass, 

 which may be pushed out or drawn in ; sometimes of a long 

 tube armed with augers or saws of wonderful finish, to prepare 

 for eggs ; or again of a tube which may also serve as a sting. 



Most authors state that insects copulate only once, or at 

 least that the female meets the male but once. My pupil, 

 Clement S. Strang, who made a special study of the structure 

 and habits of bugs during the past season, noticed that the 

 gquash-bugs mated many times. It would be interesting to 

 know whether these females possess the spermatheca. In some 

 cases, as we shall see in the sequel, the male is killed by the 

 copulatory act. I think this curious fatality is limited to few 

 species. 



To study viscera, which of course requires very careluTdis- 

 section, we need more apparatus than has been yet described. 

 Here a good lens is indispensable. A small dissecting knife, 

 a delicate pair of forceps, and some small sharp-pointed dis- 



