130 



Annals of the South African Museum. 



other genera discussed ; yet, taking sigilla as the criterion, two distinct 

 classes can be distinguished, to each of which a generic name had 

 previously been given on other and less reliable characters. 



Ancylotrypa. Posterior sternal sigilla oval, marginal to submedian ; 

 and their distance apart always exceeds the width of the labium, and is 

 also much greater than their long diameter. The distance between their 

 inner anterior margins greatly exceeds the distance from the latter to 

 the margin of the sternum. 



Pelmatorycter- Posterior sternal sigilla large, oval or pear-shaped, 



B 



FIG. 12. A. Ancylotrypa cornuta $ . B. Pelmatorycter namaqueti sis $ . 

 C. A. pusilla $ . D. P. palUdipes $ . 



and median to submediau in position ; the distance apart usually less 

 than, and rarely equal to, the width of the labium, and also seldom 

 exceeding the long diameter of the sigilla. The distance between the 



o o o 



inner anterior margins is considerably less than from the latter to the 

 margin of the sternum. 



In both genera the 2 anterior pairs of sigilla are small, less distinct, 

 and marginal ; in Pelmatorycter the 2nd pair are submarginal. 



The characters given in the original generic descriptions are not of 

 primary importance, the dentition of the tarsal claws being especially 

 variable ; the eyes, however, are of some importance, since in Ancylo- 



