XII] 



ASTAC0S 



177 



broad intersternal arthrodial (i.s, Fig. 71) membranes which permit 

 of a great amount of downward bending of the abdomen, for in 

 such a movement they must of necessity be much puckered. On 



the outer side of the insertion of the limb there is a short sclerite 

 running to the tergum, called the epimeron. The bent down edge 

 of the tergum is distinguished as the pleuron but there is no line 

 of demarcation between it and the rest of the tergum. 



s. & M. 12 



