sexual apparatus of Acentropus. 



159 



The general character of the anal appendages may be 



described as follows : — 

 From the upper margin 

 of the last segment 

 proceeds a large boat- 

 shaped lobe^which, how- 

 ever, when viewed from 

 above, is longitudinally- 

 canaliculate in the mid- 

 dle, instead of being 

 provided with a raised 

 keel, hence the term 

 'boat-shaped' is only 

 strictly applicable to its 

 lateral aspect : this lobe 

 is furnished with long 

 scales proceeding most- 

 ly from its base. To the 

 end of the lobe is at- 

 tached along, somewhat 

 lanceolate, process, 

 more or less pointed at 

 its extremity, which is 

 sometimes curved down- 

 ward, and beneath, be- 

 fore the extremity, 

 there is a tendency (not 

 always appreciable) to a 

 projection, in one speci- 

 men examined amount- 

 ing to an actual tooth : 

 on the base of the pro- 

 cess there is possibly a 

 membranous tooth-like 

 {\\dejg.l&2.) structure, disappearing 



ordinarily by desiccation. The intromittent organ is at- 

 tached to a membrane lying within, and connected with, 

 the above-mentioned boat-shaped lobe. It is horny, and, 

 viewed laterally, long and acuminate, the apex being 

 acutely pointed and often mucronate. On the upper 

 side, about the middle, there is a projection, or dilatation, 

 furnished with more or less numerous, and more or less 

 minute, teeth or serrations. Viewed from beneath, the 

 apical portion of this organ expands, and is afterwards 

 contracted and produced into a slender point. From the 



