CASTES OF TERMOPSIS 519 



THE SOLDIER OF T. ANGUSTICOLLIS 



The adult soldier of T. angiisticollis is very variable in size 

 and color. Banks and Snyder ('20) state that the body length of 

 this caste ranges from 15 to 19 mm. and the writer has collected 

 some specimens 25 mm. long. In the darkest individuals most of 

 the head is black, the remainder of the body shading backward to 

 a light brown abdomen. In lighter individuals the color ranges 

 from dark brown on the head to the whitish abdomen. The head 

 is greatly elongated; the compound eyes are small, 0.08 by 0.04 

 mm., but are larger in young soldier nymphs; crescentic areas 

 are present on the frontal surface of the head similar to those 

 found on the second and third form, but even smaller, and like 

 them probably representing vestigial ocelli; the fontanel is lacking 

 in the soldier, as in all other castes of Termopsis angusticollis. 

 Twenty-five antennal segments have been counted; this number, 

 however, is probably variable. 



Although the thorax is normally wingless, in one colony, taken 

 at Pacific Grove, California, in May, 1919, the writer found three 

 young white soldiers with short wing pads (fig. 9) , together with 

 normal wingless young soldiers. It will be recalled that Heath 

 ('03) also found a few soldiers with wing pads in this genus. 



The abdomen is elongated and round in cross-section in some 

 individuals, short and much flattened in others. The legs are 

 large and stout; the lateral tibial spines are variable in number, 

 five to one, and in size, some individuals (fig. 3, g) having quite 

 large lateral spines, those always smaller than those of the first 

 form, other specimens (fig. 3, h) have very minute spines; five 

 tarsal segments are visible, and a small onychium. The anal 

 cerci have either four segments, hke the second form, or five, as 

 in the first form. Styles, genital appendices, occur in both sexes, 

 and the sexes are readily distinguished by the larger seventh 

 abdominal sternite of the female. 



Internal anatomy. The brain of the soldier is smaller than 

 that of the first and third reproductive forms, but is as large if 

 not larger than that of the second form. By comparing figure 

 4, a, b, c, d, it will be seen that the brains of the four castes of 

 Termopsis differ chiefly in the size of the optic lobes; a correlation 



