67 



Subfamily Lithocolletinae 



In the Lithocolletinae all the genera but Acrocercops have a 

 strongly elevated median ridge on the prothorax, and in all but Acro- 

 cercops and Marmara the proximal part of the labial palpi is covered by 

 the maxillae so that the lateral margin can not be traced cephalad to 

 the labrum. The genus Lithocolletis, which seems very distinct from 

 other genera in the subfamily, includes two distinct types of larvae. 

 On this basis the genus was divided into two groups designated as 

 the "flat-larval group" and the "cylindrical-larval group." Dr. Chap- 

 man in 1902 (Entomologist, Vol. 35, p. 141) proposed the name 

 Cameraria for the flat-larval group, and this name is used here as our 

 investigation shows that the cremaster is a decided genus character, 

 and, furthermore, that members of the same genus have the same type 

 of cremaster. It is therefore deemed impossible, from a study of the 

 pupal characters, that one genus could include both forms with and 

 without a cremaster. The pupae of the cylindrical-larval group stud- 

 ied, moreover, showed two distinct types of cremaster, L. lucidicos- 

 tella (Fig. 66a) having a rather broad cremaster with curved setae, 

 while in L. tiliacella and L. argentinotclla the cremaster is long and 

 slender (Figs. 66b and 64) and the setae are T-shaped, the former 

 having one such seta and the latter two. From the standpoint of 

 pupal characters these would properly form three genera. It is in- 

 teresting to note that Meyrick (Genera Insectorum, Part 128) places 

 these in different sections of the genus, and that Miss A. F. Braun 

 in her work on the "Development of the Color Pattern in Lithocol- 

 letis" (Journ. Acad. Nat. Sci. Phila., Vol. 16, Series 2, 1914) also 

 includes them as members of different groups in her phylogenetic tree. 

 The genera of Lithocolletinae may be separated as follows: 



a. Dorsum of abdominal segments with spines of the same size; caudal 

 margins of abdominal segments never distinctly elevated, 

 b. Dorsum of eaeh abdominal segment covered with spines for its 

 entire length, 

 c. Maxillae at least seven eighths the length of the wings ; labial 

 palpi almost half the length of the maxillae, their proximal 

 end not covered by the maxillae ; spines on dorsum of abdo- 

 men very small and inconspicuous except a row of six spines 



on the tenth segment Acrocercops Wallengren. 



cc. Maxillae not more than one third the length of the wings ; 

 labial palpi about one third the length of the maxillae, their 

 proximal end covered by the maxillae ; spines on the dorsum 

 of the abdomen small but distinct, with a few larger ones on 

 the tenth segment Leucanthiza Clemens. 



