26 DONALDSON BODINE. 



at the crest of each ridge. These ridges Avhen greatly developed 

 extend beyond the apex of the slope and give the whole an appear- 

 ance of being covered with fine points. This modification may be 

 carried to an extreme. Cerura cinerea, represented in Fig. 37, will 

 show an unusual degree of development in this direction. As a 

 rule, however, the plates are smaller and more uniform, and form a 

 regular imbricated surface, such as is found in Hemileuca maia or 

 Papi/io po/i/.reiies, Figs. 38 and 39. 



In a smaller number of cases the surface rises to the plates on each 

 side, making a double slope, with the plate at the crest. This may 

 be illustrated in the antenna of Daremvia lOidv/om, Fig. 33. 



As might be expected, the extent to which these surface modifica- 

 tions of tlie structure of the chitin is carried depends largely upon 

 the development of scales. Where the antenna is heavily clothed, 

 we find usually less departure from the primitive form of surface, 

 especially if the scales are closely and compactly arranged. In most 

 cases the surface of the scape and pedicel is practically smooth. 

 This is doubtless in consequence of the covering of thick tufts of 

 long slender scales, and also because the abundant scales of the 

 vertex of the head aff'ord it sufficient protection. 



DISCUSSION OF FAMILIES. 



This chapter will contain a discussion of the antennae of Lepi- 

 pidoptera by families, or groups of families, as the case may be, and 

 will give my interpretations of the evidences they pi-esent, which 

 may be of taxonomic value. In this discussion the provisional clas- 

 sification of Pi'ofessor Comstock will be followed, because it is the 

 one with which I am most familiar and because I believe it repre- 

 sents the true relationships better than any other.* The character- 

 izations of gr()U{)s (]Uoted in the following })ages are taken from the 

 " ^Manual." It would be presumptuous for me to proi)ose any changes 

 in the classification, but where the evidence of the antennal struc- 

 tures is contrary to that of the wings, note will be made of such con- 

 tradictions as indicating the need of further study of the group. To 

 be complete, a classification must take into account all the structures 

 found in the body, and it was for the pur})ose of adding the evidence 

 of one more organ that the present work was undertaken. In most 

 of those species where the antennae of the males and females differ 



* Mamial for tlie Study of Insects. John Henry Comstock and Anna Botsford 

 Comstock, Comstock Tub. Co., Itliaca, N. Y., 1895. 



