1893.] 139 [Packard. 



The Life Eistories of certain Moths of the Families Ceratocampidm, 

 Eemileucida; etc., with Notes on the Armature of the Larvm. 



By Alpheus 8. Puckard. 



{Read before the Amerlaan Philosophical Society, March 17, 1S93.) 



Family Ceuatocampid.e. 



Judging by the larvie alone, this group is well circumscribed. The 

 most generalized forms are Dryocarapa and Anisota. In these there is no 

 "caudal horn," and the single median dorsal spine on the ninth abdomi- 

 nal segment in Dryocimpa is about one-third as long as that of Anisota, 

 ■while in Sphingicampa the spine is reduced to a minimum. That the 

 larva of Dryocarapa is the simplest of the family is also shown by the 

 fact that the two rudimentary spines on the third thoracic segment are 

 shorter and less forked, and the other abdominal spines are shorter than in 

 the other genera. 



The suranal plate has the shortest spines in Sphingicampa and longest 

 in Anisota, being of a length intermediate between these two genera in 

 Dryocampa, in which, however, they are still long. 



Sphingicampa may be regarded as a transitional form connecting Dry- 

 ocampa and Anisota with Eacles and Citheronia, 



Eacles in its first larval stage, as compared with that of Sphingicampa, 

 differs in the following respects : 



The prothoracic segment is armed with spines ; the thoracic spines are 

 in Stage I forked at the end ; the caudal horn is much longer and slen- 

 derer, and also forked at the end ; also there is a single median spine on 

 the ninth abdominal segment. Eacles is peculiar in the abdominal seg- 

 ments being marked with two black transverse stripes. 



Aglia tau, a connecting link between the Ceratocampidm and Saturniidce 

 and the type of a new subfamily, Agliince. In this European Bombyciue 

 moth we have surviving, side by side with the generalized Salurnia, a most 

 interesting form, which is a Ceratocampid in its earlier larval stages, the 

 larva in its last stage and the moth being very near the Saturnians, 

 although it does not spin a cocoon, and should be regarded as a Cerato- 

 campid. We could not have any clearer demonstration of the origin of 

 one family from another by direct genetic descent. 



The transformations of this form, originally figured in Duponchel et 

 Guenee's Iconographie* (Tome ii), has been more fully elaborated by Mr. 

 Poulton. 



Having received, through the kindness of Dr. Heylaerts, a j'oung larva 

 of Aglia tau in its third stage, I have been able to compare it with Eacles 



* Gu6ai5e states that after attaining its full size : " Ella se retire a la surface de la terre, 

 entre des mousses et des debris de v^getaux qu'elle attache avec de la sole, et elle s'y 

 change en une chrysalide grosse, courte, d'uu brun fonce saupaudrj de grisatre, et dont 

 I'anus est termini par uue faisceau de pointes recourbJes.'' 



