266 Dr. Malcolm Burr on the Opisthomeres 



I am bound to admit that it looks as though we have 

 here a fusion of the metapygidium with the telson. 

 Apterygida albipennis shows a similar structure. 



Fio. 17. — Apterygida albipennis, Meg., S ■ 



In the primitive Arixenia, we should expect to find 

 generalised opisthomeres ; it is therefore surprising to find 

 in the male of A. jacobsoni only two plates, the basal one 

 nearly square, the apical one of the same breadth, but 

 less than half as deep. Neither show any trace of suture 

 or fusion, nor any specialisation. 



Fig. 18. — Arixenia jacobsoni. Butt, S. 



The Gonapophyses. 



If we lift the last sternites in the females of certain 

 Protodermaptera, we find two sets of paired appendages 

 termed the gonapophyses, supposed to be the homologues 

 of the four valves of the ovipositor of the true Orthoptera. 



Zacher was the first, as far as I am aware, to call atten- 

 tion to these structures in the Dermaptera, and he 

 figures a few instances. "We reproduce a copy of his figure 

 sho\ving the under surface of the extremity of the abdomen 

 in the female of a species of Kalocrania, where BB 



