70 THE CANADIAN ENTOMOLOGIST. 



absolute generic distinction. Sometimes all the tibia are spinulated, 

 sometimes middle and hind tibia only, and sometimes only the middle 

 tibia ; the number of tibia spinulated has no generic value. The posterior 

 tibia has usually (if not, as I believe, always) two pairs of spurs, one 

 pair near the middle and the other at the tip. The middle tibia have a 

 single pair at the tip. 



The anterior tibia varies greatly in shape and armature, and its modi- 

 fications afford good generic characters. Usually it is proportionate, and 

 unarmed at tip ; sometimes it has spinules at the extremity, and some- 

 times a single strong claw ; sometimes the spines and claw co-exist. 

 Neither of these alone authorize generic distinction. Sometimes the tibia 

 is very short, exceeded in length by the first tarsal joint and variously 

 armed at the tip ; this suffices for generic distinction irrespective of the 

 armature. This latter is various, sometimes consisting of spines and 

 sometimes of claws at the tip. Very often the tibia, besides being short- 

 ened, is also flattened and becomes broader anteriorly ; this also author- 

 izes separation from a genus with the fore tibia equal, no matter what its 

 length. In a few genera the anterior tibia is almost fossorial ; Trkopis, for 

 instance, having a very heavy, long inner claw, and three shorter but 

 equally heavy claws outwardly. Tamila has very heavily armed tibia, and 

 in Helioloiiche the inner claw is nearly as long as the tibia itself, and not 

 much more slender than the tarsi. The variations in the number of claws 

 or their length alone, do not authorize generic separation, but added to a 

 change in the form or proportion of the tibia, they would. 



The males sometimes have a brush of long hair at the inner side of the 

 anterior tibia, but this has no generic value. 



The femora vary little, and so far as I know, not at all in the American 

 forms ; in the European forms two genera have them clavate. Such a 

 modification would support a genus. 



The tarsi, so far as I know, are always spinulated. They are some- 

 times distinguished by long fluffy hair on the anterior and middle pair 

 (Eriopus), or by long, dense, vertical, upright hair on the posterior 

 (Remigia). These modifications being sexual purely, have no generic 

 value. 



The ^aifigs vary greatly in form and proportion. Usually the primaries 

 are elongate, widening gradually outwardly, with rectangular or obtuse 

 apex, slightly oblique outer margin, rounded hind angle and straight inner 



