//. ACBBArA: SOLPUGIDA. 



449 



Lung sacs, which are true appendages without hmg leaves, occur 

 on abdominal segments four to six, and are eversible. The ovary 



Fig. 463. — Kceiienia niirabilis.* (From Wheeler.) 



is unpaired, the testes paired. There is a circumojsojjhageal nerve 

 ring and a single abdominal ganglion. Xo Malpighian tubes 

 occur. A'ce?ienia.* 



Order IV. Solpugida (Solifugse). 



In these the cephalothorax is broken up into a head bearing the 

 chelicerfe, pedipalpi, and the first pair of legs; and three posterior 

 free somites, each bearing a pair of legs, thus giving these forms a 

 certain resemblance to the Ilexapoda (infra). The chelicerie are 

 strong and chelate, the pedipalpi are simple and are used iu walk- 

 ing, while the first pair of legs are tactile. Respiration occurs by 

 four pairs of trachere, the first of which opens between the first and 



