CASTES OF TERMOPSIS 507 



In a young immature female nymph of the first form with thin 

 wing pads, about 10 to 12 mm. long, the reproductive organs 

 present the following appearance, as seen in figure 11. The ova- 

 ries contain many egg tubes, consisting of numerous eggs in Unear 

 rows, the two ovaries being connected with each other by threads 

 of connective tissue, the terminal filament, not shown in figure 

 11, as it is easily broken in dissection. A few of the proximal 

 ova are enlarged, showing that the growth period has begun. 

 The oviducts are narrow as yet, but bear at their junction a small 

 trilobed seminal receptacle, or spermatheca. The colleterial 

 gland is much convoluted, but its tubules are of narrow diameter. 



The reproductive organs of a mature female nymph of the first 

 form with thickened wing pads, 12 to 13 mm. long, are shown in 

 figure 12. The largest ova are nearly three times the size of those 

 of the immature nymph just described; many more enlarged eggs 

 are present, and the oldest, or proximal ones, are surrounded by 

 a peUicle of small cells. The oviducts are broader, the seminal 

 receptacle, sr, has grown, and the colleterial gland, cl, is larger as 

 a whole and has tubules of greater diameter. 



In male nymphs of the first form a similar correspondence be- 

 tween age and size of the reproductive organs may be observed in 

 the two phases of young immature nymphs with thin wing pads 

 and mature nymphs with thick wing pads. In figure 16 the 

 reproductive organs of a mature male nymph of the first form are 

 shown. The testes, t, consist of many short rounded lobes, the 

 vasa deferentia are slender and open into the basal part of the 

 paired seminal vesicles, sv, which are greatly branched and con- 

 voluted, the convolution increasing with age. The seminal 

 vesicles after their junction with the vasa deferentia open into 

 the ejaculatory duct which ends in a short muscular penis. In 

 stained whole mounts of the male reproductive organs, which 

 have been dissected out from the surrounding fat-body, zones of 

 developing sex cells in the testes are clearly seen even with a low- 

 power lens. 



Sections of the male reproductive organs of a mature nymph of 

 the first form, made by sectioning the posterior end of the abdo- 



