104 John Henry Comstock 



GG. Moths in which the anal veins do not anastomose in 

 such a way as to appear to be branched outwardly. This 

 group includes two families, which so far as their wing-struc- 

 ture is concerned are more closely allied to each other than is 

 either of them to either of the preceding families. In each of 

 the two families included here there is frequently exhibited a 

 marked tendency towards the abortion of radius of the hind 

 wings. 



H. Moths in which the branches of radius of the fore wings 

 tend to anastomose, forming an accessory cell or cells (Fig. 

 12). The larvae are wood borers. Family Cossid^. 



HH. Moths in which the branches of radius of the fore 

 wings do not anastomose (Fig. 16, 17). The larvae are "slug- 

 caterpillars " and feed on the leaves of plants. 



Family Limacodid^. 



EE. The Specialized Fre7iuhLrn-conservers . — Moths in 

 which the anal area of the hind wings is reduced, having less 

 than three anal veins, and in which that part of media which 

 traverses the discal cell is usually wanting. 



This division of the order is a very extensive one, including 

 the greater number of the moths ; it is represented in our 

 fauna by thirteen groups, which are either of family or super- 

 family rank. 



In several cases a familj' seems to be quite isolated ; while 

 in other cases several families can be brought together into a 

 single larger group. I recognize two such groups. But in 

 neither case does the group seem to be sufficientl}^ homoge- 

 neous to be regarded as a superfamily ; it must be regarded in 

 each case as a provisional arrangement, which will be of use 

 until the affinities of the families are better understood. 

 These two groups are defined under FF and FFF below. 

 Under F and FFFF are grouped the isolated families. 



F. The family Dioptidae represented b)^ the genus Phry- 

 ganidia, which occurs in California, seems to represent 

 a distinct line of development. For it presents a com- 

 bination of characters that sharpl)' distinguishes it from 

 all other known members of our fauna. The anal area of the 

 fore wing is reduced, vein IX alone being retained (PI. Ill, 



