802 The American Naturadist. [September, 
that the genus is the type of a distinct family, and forming a 
line of descent somewhat parallel with and near to the Litho- 
siide. The pupa has the labial palpi well developed, and the 
paraclypeal pieces large. The end of the abdomen is rounded 
and unarmed, in adaptation to its enclosure in a dense cocoon. 
Family Syntomidex.—The position of the Syntomide is diff- 
cult to determine. The pupa is obtected, though it has in 
Scepsis retained the labial palpi. Judging by the larval and 
pupal characters the family stands much nearer the Arctiide 
than the Zygeenide, but yet is more generalized than the 
former. In the venation the group stands near the Arctians, 
i. e., the venation of the generalized Ctenucha approximates 
that of Epicallia virginalis, while in Didasys and Syntomis the 
venation is more aberrant and modified; so also in the long 
tufted larvee of Syntomis and Cosmosoma, compared with that 
of Ctenucha, in which the tufts are less developed and special- 
ized. 
On the following page is a provisional genealogical tree of 
the order, based mainly on the pupal and imaginal characters. 
