2 BULLKTIX 48, UNITED STATES NATIONAL MUSEUM. 



in wbicb the palpi are slender, curving np^yard and exceeding tlie head, 

 none are Deltoids in which the two pairs of Avings are similar in size 

 and niaculation or have a geometriform ornamentation extending on 

 both wings. Further, with the exception of Helia, all Deltoids with 

 palpi of the character last described have the lore legs of the male 

 modified, clothed with tufts or pencils of hair, and always with aborted 

 tibia. 



With the exceptions stated, the series does not differ from other 

 Noctuids in any essential features; yet it will be worth whde to 

 mention some of the other main characters. The liead is always small, 

 yet never retracted, and often prominent. In none of our species is 

 the tongue aborted or even weak, so all of them are capable of feeding. 

 The eyes are usually prominent, semigiobose, though never very large; 

 always naked, though in some genera — only one in our fauna — fringiul 

 with hairy lashes. Ocelli are present in all our forms, situated close to 

 the compound eye, but distinctly variable in their position relative to 

 the posterior margin of the eye. In the Herminiini they are almost as 

 far back as i)ossible, while in Hypenini they are almost in the middle 

 of the crown. The \)o\ut of insertion of the antennse varies somewhat; 

 but as in the matter of the ocelli our material is not yet sufficient to 

 enable us to make studies on all the points involved or to generalize. 

 The structure of the antennai is exceedingly interesting from the 

 character of the sexual modifications; but this subject will betaken 

 up again further on, and I need only say that they vary from simple to 

 lengthily pectinated. 



The character of the i)alpi has been already referred to. 



The body is slight in most instances, never very robust. The thorax 

 is closely scaled in general, tufted only in the Hypenini, where a lobust 

 structure is characteristic of the males. The abdomen is usually 

 cylindric, without sexual differences, but in the female terminating in 

 an abrupt point, while in the male it is truncated. While it is never 

 short, the abdomen rarely exceeds the anal angle of the secondaries 

 more than a little, and it as rarely fails to reach that point. Tuftings 

 are only found in the Hypenini, where, in most of the species, there is 

 a series of little round, trunca'ted, dorsal tufts, composed of upright 

 scales and very easily rubbed off. 



The legs are usually long and slender, though hardly weak. The 

 thoracic structure tends to an elongation of the parts, the coxa^ being 

 in all cases well develo])ed. The fore legs are short, the tibia- usually 

 short in comparison with the femur; but m the males of the Her- 

 miniini the modifications are very curious and will be again referred 

 to. The middle and posterior legs are longer, more as in the Pyralids, 

 with extremely long and unequal tibial spurs, terminal on the median, 

 terminal and at apical third on the posterior ]>air. The legs are closely 

 scaled as a rule, but in some of the male Hypenini they, as well as the 

 entire thoracic ])arts, become haiiy or even woolly. 



