AMERICAN LEPIDOPTERA. 7 



Senilis resembles the last preceding two species in the serrated and 

 bristle-tufted antennae; but in little else. The ground color is a 

 peculiar, dull, rusty brown, on which the slightly darker lines trace 

 out the usual maculation. In all essentials we have the maculation 

 of nictatans (atlantica) with the color of Pachnobia littoralis, for 

 which this species might be at first mistaken. The harpes of the 

 only male before me are broken at the tip, but the main clasper is 

 large, semicylindrical, very broad at base and tapering to an acute 

 tip ; the margins irregular. At the base of this is a small, pointed, 

 beak-like process. 



Serrata differs from all its allies in the well-pectinated antenna? of 

 the male. It is bright yellowish red-brown in color, with all the 

 ordinary spots white and contrastiug. It thus resembles, superfi- 

 cially, the species of the next series ; but the wing form is not as 

 described for that, nor does it have the characteristic thoracic tuft. 

 Its antennal structure, combined with the ornamentation, will always 

 identify the species. The male characters resemble in general those 

 of juvenilis. The harpes are almost parallel, the tips obtuse and 

 not specially modified. There is a long, stout and slightly curved 

 clasper arising within the middle of the harpe and extending more 

 than half way to its tip, to a point where a second broad, short, 

 obtuse process arises near the lower margin. 



The species of Papaipema are more closely allied, tho' several of 

 them separate off easily. 



It is in this series, and particularly in the species allied to rati In, 

 that confusion has occurred in collections. Just what the distinctive 

 characters are no one seemed to know : several names in the lists 

 were not represented by specimens in any collection, and the range 

 of variation was in doubt. It was assumed to be great, because of 

 what was known of nitela and nebris, and of the forms of nietitans. 

 Thus it came that two species were associated under rutila and two 

 under marginidens. The latter species was often named limpida, 

 and this was due to the fact that it was so named in the Graef collec- 

 tion, from which I obtained my first names in the Noctuidse. The 

 name remained on my examples, from which determinations were 

 made for others, until I saw the type in the British Museum ami 

 called attention to the matter in the catalogue. It appears now that 

 our species are much more constant than has been supposed and that 

 there is really very little variation. 



Cerina is readily distinguished by its lemon yellow ground color 



TRANS. AM. ENT. SOC. XXVI. MAY, 1899. 



