Occasional Papers of the Museum of Zoology 49 



Trachelodesmus ancylophor, sp. nov. 

 PI. 19, Figs. 126, 127 



General color light horn-brown, a considerable portion of 

 metazonite and prozonite above darker, dusky, in the type the 

 collum and vertex of head with a network of dark lines. Legs 

 and antennae fulvous. 



Body rather slender, widest near middle and narrowing 

 very gradually forwards, the anterior constriction including 

 particularly the third and fourth segments. 



The head not granular or tuberculate. smooth throughout. 



Collum a little narrower than head, inclusive of cardines 

 of mandibles. Margin widely and evenly convex over ante- 

 rior and lateral regions back to caudolateral angles, which are 

 subrectangular ; caudal margin convex on each side just within 

 the angle, the median region nearly straight. The dorsal sur- 

 face presents along the caudal border about ten larger, more 

 elevated, rounded tubercles, between which are wedged in 

 smaller tubercles forming in general two rows, one in line 

 with anterior and one with posterior borders of the larger 

 tubercles ; the remaining portion closely covered with smaller 

 and lower flattened tubercles back of anterior border, such 

 as occur in Trachelodesmus constrictus Peters. A row of 

 about six widely separated setae just behind the depressed 

 anterior border. (PI. 19. Fig. 126.) 



The second tergite with two irregular series of mostly 

 large tubercles across median region ; the principal tubercles 

 on each side are much larger than those of median region, 

 there being behind them a caudal series of much snUiller 

 tubercles ; a large, blunt tubercle at anterolateral corner is car- 

 ried forward against the end of the collum. Third tergite 



