302 THE CANADIAN ENTOMOLOGIST 



Mallophagan species. The family contains a consideralile number 

 of unrecognized generic groups, for the separation of which char- 

 acters must be used that have heretofore been almost entirely 

 neglected. Of these characters those to be found in the chictotaxy 

 of the posterior femora are perhaps of first inip<^rtance. The spines 

 on the ventral face of these femora may be arranged in a series of 

 "combs," which are always associated with similar combs upon 

 certain abdominal sternites, or they may be arranged in a distinct 

 patch or brush, usualK-. associated with similar brushes on the 

 abdomen, or they ma\' be irregularly arranged or entirely lacking. 

 The taxonomic value of the combs has already been pointed out 

 by Harrison in the case of Colpocephalum (in its restricted sense) 

 and Tetrophthalmus, but the brushes ha\e apparentl>- not, as yet, 

 been noted in literature. 



Of probably secondar\- importance are other characters, in- 

 cluding the presence of either a slit or notch in honi ot the eye, 

 the segmentation of the thorax, ilie presence of hea\y spines on 

 the ventral side of the hccid, the character of the cha^totaxy of the 

 abdomen, the genitalia of the males and the presence of peculiar 

 structures in the gular region. 



Having in mind these characters, the group which this paper 

 considers may be defined as follows. 



Menoponida' with more or less distinct patches or brushes of 

 spines upon the ventral face of the posterior femora and upon 

 certain abdominal segments. Thorax three-scgmente<l, usually 

 distinctly so, although the mesothorax is sometimes much reduced. 

 Head of a very characteristic shape, the temples \ery prominent, 

 projecting well beyond the lateral margin. 



The following ke\- will scr\e to distinguish the included genera: 



1. Head with a distinct notch fnot a slit) in the lateral margin 



just before the eye 2. 



Lateral margin of the head continuous to the e>e 3. 



'2. Femoral and sternal patches composed of spines which are 

 distinctly smaller than those constituting the general cha.'to- 

 tax\- and are very closely crowded together. 

 Genus Heleonomus, n. gen. 



