6o Bulletin 64. 



CC. Valve not triangular ; harpe elongate and with one or 

 more spines near the tip. {Subdivision II.) 

 D. An accessory spine near the tip of the harpe. PI. 



VIII., Fig. 15. elegans. 



DD. Many short spines on the tip of the harpe. PI. VIII., 



Fig. i6. turbatellus. 



DDD. A pair of spines on the tip of the harpe forming a 

 crescent as seen from behind. PI. VIII,, Fig. 17. 



extorralis. 

 CCC. Valves strongly flattened ; harpe never elongate and 

 narrow ; accessory spine when present broad and plate- 

 like or very short. {Subdivision III. The Agitatellus Group. ^ 

 D. Harpe nearly as wide as valve. 



E. Harpe terminated by a retangular spine, edge 



smooth. PI. X., Fig. 22. agitatellus. 



EE. Harpe terminated by a recurved spine, and with 

 chitinous processes upon the edge. PI. IX., Fig. 18. 



inyiotatellus. 

 DD. Harpe much narrower than the valve at the base. 



PI. X., Fig. 23. minimellus. 



DDD. Harpe reduced to a very short spine. 



E. A thick tuft of very long hairs near the harpe. 



PI. IX., Fig. 19. topiarius. 



EE. No thick tuft of very long hairs near the harpe. 

 PI. IX., Fig. 20. albellus. 



DDDD. Harpe not a short spine. 



E. Uncus not strongly reduced, tips of valves oval. 

 F. Harpe flattened, recurved. PI. X., Fig. 24. 



albodavellus . 

 FF. Harpe flattened, concave, curved ventrad. PI. 

 XL, Fig. 26. laqueatellus. 



EE. Uncus greatly reduced, represented by two very 

 thick tufts of curved hairs. PI. XI., Fig. 27. 



satrapellus. 



