Rev. F. D. Morice on Armatures, etc. of Andrcna. 231 



to be of much practical use, being difficult to examine 

 without complete dissection, certainly less conspicuous, and 

 I think less constant than those of the 8th. Again, in the 

 armature I propose to confine attention to the stipites. 

 Sometimes, no doubt, the sagittaB have specific characters, 

 e.g., basal dilatations of different extent and form. But 

 their position, with deflexed tips, lying almost always out 

 of sight, makes investigation of them troublesome, and on 

 the whole I have thought it best to omit them both in 

 descriptions and drawings. The stipites, on the contrary, 

 show easily examined and often striking differences, as 

 soon as the armatures are exposed and put in similar 

 position. The direct dorsal view displays them quite 

 satisfactorily, and I have adopted this aspect in all my 

 figures of armatures. 



The characters of the 8th segment are equally remark- 

 able, but to realise them all, two aspects at least are 

 required — the ventral and the lateral. Very pilose speci- 

 mens require also to be viewed in a third aspect, the 

 dorsal : i.e., that which shows the interior (concave and 

 naked) side. Otherwise the hairs conceal or disguise the 

 actual outline of the segment, a character of great constancy 

 and importance. 



Practically then, we have to deal with (1) the stipites 

 viewed dorsally, and (2) the 8th ventral segment or 

 'valvula ventralis' viewed ventrally, laterally, and some- 

 times dorsally also. But first a word may be said, as to 

 the curious and interesting forms and respective situation 

 of the armature and ventral segments in the apex of a ^ 

 Andrcna s abdomen. 



In the armature the two pairs of claspers {stipites and 

 sagittx) appear as if mounted on a cushion-like rather 

 transverse base (the cardo). The stipites throughout the 

 genus are conspicuously dilated for about half their length 

 from the base upward, the other (apical) portion of them 

 being comparatively very narrow. Consequently, seen 

 dorsally, each stipes resembles a broad convex plate or 

 ' lobe ' with a ' process ' attached to it ; and for convenience' 

 sake we may perhaps speak of it as consisting of a ' lobe ' 

 and a ' process,' though in fact each stipes is made all in 

 one piece and the difference lies only in the extent of its 

 dilatation. 



The stipites do not quite meet on the ventral side ; but 

 on the dorsal side in front their ' lobes ' are always more ox 



