37 



IV. Conclusions drawn from a study of the Genera 



Hypena and Herminia 



BY AUG. R. GROTE. 



I HAVE recently identified M. Guenee's descriptions of North 

 American Deltoids in a series of Papers contained in the Fourth 

 Volume of the Transactions of the American Entomological Society. 

 To the third Paper I have given a list of our species. I have en- 

 deavored to separate as accurately as my ability, and the material as 

 yet placed at my disposal, would allow me, a number of species 

 which might be loosely classed under Schrank's genus Hj-pena. 



I have considered Hypena as restricted by Hiibner in 1816. 

 Hiibner cites under this name the European species, Palpalis, Deci- 

 malis, Ohsitalis, and Rostralis. The genus thus corresponds with 

 Lederer's second Group of Hypena, and is typically represented in 

 our Fauna by Hypena Humuli, Harris. In this species the com- 

 pressedly elongated labial palpi extend much beyond the head, and 

 are as long, or nearly as long as the thorax ; the third joint is con- 

 tinuous and shortly scaled. The primary wings are narrow and 

 crambiform, without a lappet at internal angle. Our species are 

 HYPEifA EVANiDALis, RoUiisou, and Hypena Humuli, Harris, 

 from the Eastern and Middle States, and Hypena citata, Grote, 

 from Alabama. 



I would follow this genus by our common species from the At- 

 lantic District, the Hyhlaea scahra of Fabricius, in which the still 

 narrow wings swell suddenly at outer third, and are developed at 

 internal angle somewhat as in Pseudothyatira, Plusia or even Con- 

 chylis, and have a sinuate internal margin. The third joint of the 

 palpi is neither so shortly scaled, so continuous, nor so long as in 

 Hypena. An exceedingly valuable communication made to me by 

 Mr. Lintner discovers the fact that M. Guenee's Hypena erectaJis 

 is the female form of this species. There is then a sexual character 



