62 



MEMOIRS OF THE NATIONAL ACADEMY OF SCIENCES. 



Imago. — S and $ head as in Anisota, but tending in front to be more triangular, and nar- 

 rower towai'd the labrum; it is widest in A. hicolor, narrowest in A. hisecta and especially in 

 A. montezuma (PI. XIX, lig. G). Antenna? of S bipectinate, with 17 to IS pairs of pectinations 

 which are exactl_y as in Anisota; the 12 joints of the filiform extremity very short; in 9 simple, 

 except in A. bicolor, which has 16 pairs of short, thick, subclavate pectinations, a single pair to 

 each joint. Palpi short, varying in length, just visible, not reaching the front. Maxilla' varying 

 in length, not visible in ^1. hicoJor and A. heiUghrodtii, but in ^1. giihanguhda, the more primitive 

 form, they are comparatively well developed, though separate from each other; they are curled 

 up, and are nearly as long as the filiform tip of the S antenna>; they are also present in A. vardit, 

 but very slender and short. Fore wings either of the usual generalized form, with the costa 

 convex toward the apex, the latter obtuse, and the outer edge full {A. hicolm^ A. qnadriJineata, 



Fig. 6.— Distribution of the subfamily Ceratocampinaj. 



A. heiliglrodfi! and ^1. (dholineata), and the hind wings rounded; or i\\e\ are triangular, with the 

 outer edge oblique, not full, and the hind wings subtriangular, and not roacliing beyond the basal 

 two-thirds of the abdomen. The abdomen of the $ is acute at the end and witli a tuft on each 

 side of the tip in ^1. fiiihangulata. 



Venation: Much as in Anisota, there being no vein III.,; vein II Ij arises luidway between 

 the anterior discal vein and base of common stalk of veins III3 and HI/, the greatest departure 

 is in A. .mlxingidata (PI. XXXVIII, figs. 1. la) where IIIj arises at the same point as the anterior 

 discal vein, in front of the origin of vein IV.,; venation of hind wings nearly' identical with that 

 of Anisota. 



Coloration: Ocherous, with the hind wings more or less pink; the markings diffei- very 

 much in the difi'erent species; in ^1. l>iviiJor there are two twin discal dots, in ^1. Jieilighi'ddtii the 

 fore wings are stone gray; in ^1. alhoJineata the lemon-ocherous wings are crossed bj^'conspicuous 

 white lines, and in A. hlxecta there are no discal spots, while in ^4. suJiangnlata and ^1. monteziona 

 there is a large discal spot on the underside of tiie fore wings. 



