THE CANADIAN ENTOMOLOGIST. 169 



As carlince Ramb., Staudinger has sent a pair of the small Scelothrix from 

 the Southern Tyrol, which are nearly related to alveus and serratulce, but 

 may be distinguished from them particularly in having narrower and more 

 acute wings and less expanded hind margin (their fore and hind angles 

 the more prominent on that account.) Three males taken upon the 

 Gemmi well accord therewith. I would only regard them as a somewhat 

 degenerated mountain variety of alveus. 



Nisoniades. 



Antennae half as long as the fore-wings, their club somewhat com- 

 pressed, slender, gradually dilated and then narrowed and more or less 

 acutely produced, regularly curved, lunate-falcate. Locklet long. Palpi 

 projecting upon the front to nearly twice the length of the eyes, with long 

 and thick hairs, but less coarse than in Pyrgus and Scelothrix ; the apical 

 joint thick, bluntly conical, somewhat bent. Tibise unarmed, and without 

 the tuft,* but with long hairs. Fore- wings triangular, outer margin not 

 toothed, fringe unicolored. Male with longer costal fold. 



The peculiarly native country of this genus, scarcely more than repre- 

 sented in Europe, is North America. Scudder enumerates sixteen species, 

 based chiefly upon differences in the form of the abdominal appendages, 

 several of which, however, Edwards will not acknowledge to be good 

 species. The characteristic feature is the form of the club of the antennae, 

 which is fusiform when stretched out, but which takes the form of a nar- 

 row crescent when in its regularly curved condition. This fundamental 

 form is constant ; the stoutness of the club and its degree of acuteness 

 differs according to the species. In some American species it is very 

 slender and finely pointed ; in others, as in our Tages, it is thicker and 

 more blunt, but never 'so suddenly rounded as in the preceding and fol- 

 lowing genera. 



* In a letter received from Dr. Speyer as this is passing through the press, he 

 desires to make the following correction in this diagnostic feature. The tibial tuft (see 

 also foot of page 126) is not reliable for generic separation. A critical examination 

 made by him of some of the species of Nisoniades, has shown its presence in Persius and 

 Icelus; in the latter, quite strong. Brizo, although so closely related to Icelus, is without 

 the tuft. The detection of this marked difference in these two allied species, establishes 

 their specific value, which has been questioned, and also shows that the presence or 

 absence of the tuft is only of specific importance. — L. 



