14.^ THE CANADIAN ENTOMOLOGIST. 



it shall be shown that the differences given are such that ^4. Tex an a s\\on\d 

 be considered to be only a well marked variety. 

 The differences are : — 



1. The vertex is rounded, convex above and before, very slightly de- 

 pressed longitudinally in the middle. The vertex of Americana is strongly 

 flattened above, and cut off sharply anteriorly. 



2. The last joint of labial palpi is more thickened, the suddenly co- 

 arctate tip shorter and truncate on the extreme apex. The same joint of 

 Americana is less thickened, the tip longer and pointed. 



3. The prothorax is a little shorter, equally broad in front and near 

 the mesothorax. In Americana the prothorax is visibly narrowed before, 

 so that its breadth near the head is only a little more than half its breadth 

 near the mesothorax. I consider the structural differences of the head, 

 thorax and wings important, and was indeed induced only by them to 

 separate the two species. The difference of the spots on the wings is less 

 important, the more so as I have noted, Stett. Ent Z., xix., p. 124, a 

 specimen of A. occitanica from Russia with similar spotted wings as in 

 Americana. 



4. All wings are sharper pointed, the hind wings are narrower, and the 

 apex more falcate. The wings are less spotted ; the space between fourth 

 and fifth vein is without spots, the space between subcosta and radius 

 nearly spotless ; the hind wings less spotted. 



5. The color of the body below is yellow, the legs nearly yellow ; the 

 abdomen above yellow with a longitudinal brown band, divided in the 

 median line ; on each side a lateral dark band ; the segments 5 to 7 with 

 a small yellow dot on each side nearer to the base. The appendages of 

 the male are short, 3 m.m. long, cylmdrical, straight, rounded on tip, with 

 black hairs. 



4. Acanthaclisis fallax Rbr. 



I am not able to give now an exact and sure opinion of this species, 

 as my 1 2 specimens were destroyed in bringing over my collection. Of 

 these, seven males were from Brazil and Guiana (M. senilis Klug, still 

 present in the Berlin Museum), and from California. I had provisionally 

 separated five of these from Cuba and Venezuela (not described) as M. 

 Cubana, mi/ii. But I have described them all later as A. fallax Rbr. 

 (type compared) and A. impostor Walk, (type compared) in my Synopsis 

 of Neuropt. of N. America, p. 223, No. 2. Only two specimens in very 



