CASTES OF TERMOPSIS 511 



different in the legs of a pair. Imms ('20, p. 97) notes a similar 

 arrangement and variability of the lateral tibial spines of Arclio- 

 termopsis. The size of the lateral tibial spines of Termopsis 

 varies with age, and to some extent in the different castes, as may- 

 be seen in figure 3. The first-form adult (fig. 3, a) has the largest 

 lateral spines with one margin serrate; in the mature first-form 

 nymph (fig. 3, b) they are slightly smaller and not serrate, and 

 very small in the immature first-form nymph (fig. 3, c). In the 

 second-form adult (fig. 3, d) the lateral spines are very small, and 

 and still smaller in some third-form indi\iduals (fig. 3, e) and in 

 some soldiers (fig. 3, h). In other third-form individuals and in 

 other soldiers (fig. 3, /, g) the spines are larger, though always 

 smaller than those of the first-form adult, and not serrate. Five 

 tarsal segments are distinctly seen on the inner surface of the legs, 

 but the second segment is usually not seen on the outer surface. 

 A large pulvillus or onychium is seen between the claws. In 

 these two points also Termopsis agrees with Archotermopsis. 



The sexes of the adults are seen with even greater clearness than 

 in the nymphs, as the seventh sternite of the adult female com- 

 pletely covers the eighth, and the styles, genital appendices, 

 of the ninth segment are absent in the female, but present in the 

 male. The anal cerci of the tenth abdominal segment are dark 

 brown and consist of five segments. The abdomen is more en- 

 larged in older females than in males, but the activity and the 

 relatively slight postadult enlargement of this, the largest Ameri- 

 can termite, cause surprise and disappointment to those first 

 acquainted with the greatly distended abdomens of the queens 

 in the smaller genera, Reticulitermes and Nasutitermes. 



The internal anatomy of the sex organs and fat-body only will 

 be described. 



In enlarged dealated females, 13 to 15 mm. long (fig. 10), the 

 largest eggs observed in the egg tubes were only shghtly smaller 

 than eggs that have been laid and had a similar yolk content. 

 The oviducts and especially the vaginal duct are very broad and 

 thick walled; the seminal receptacle, sr, has attained its greatest 

 size; the tubules of the colleterial gland, cl, are thick and dilated 

 and contain a fluid secretion. In the very oldest females fewer 

 and shorter egg tubes are noted. 



