1893.1 ■^"*-^ [Packard. 



At present both from their larval and their imaginal characters, and in 

 their spinning a cocoon we are disposed to consider the Hemileucid* as a 

 family closely allied to, though distinct from, the Ceratocampidae. 



On examining the European genus Endromis, we are disposed to think 

 that the family Endromidse is a natural one. It would, however, bea vio- 

 lation of the principles of classification to include Aglia with it. The two 

 genera, both as regards their larval and their adult charactei's, are quite 

 distinct. I find that Endromis versicolora has the head, palpi and antennae 

 and the hairy abdomen very closely like those of our Hemileuca maia, but 

 the median vein of both wings divides into four branches, and the sub- 

 costal vein of the four wings divides into five branches, as in U. m«j«and 

 the other Hemileucidoe. Judging by the colored figures of the larva in Euro- 

 pean works, the larva of Endromis is smooth, with a small retractile head, 

 oblique bars, and a conical caudal horn. Tlie group Endromidse is a 

 branch of the Bombycine tree, parallel to but distinct from the Hemi- 

 leucidae, and stands above the latter, connecting the group and the Cerato- 

 campidse and Saturniidai with the higher families of the Bombyces, in which 

 there are four branches of the median vein, all the fiimilies mentioned agree- 

 ing with the Notodontidse in having but three. In its general shape, the 

 small retractile head, the mode of coloration, and the caudal horn, the 

 larva of Endromis appears to be remarkably near the Sphinges. Buckley 

 describes the cocoon as "composed of an open-worked reticulation of 

 coarse black or black-brown silk threads, with round or broad oval 

 interstices, as the fabric is extremely strong, tough and elastic, covered 

 externally with moss and birch leaves firmly adherent " (iii, 65). 



It is interesting that in the transformations of RhescyiUlds erythrinm, as 

 figured by Burmeister, we have a parallel to the case of Aglia tau. The 

 fully grown larva is smooth-bodied and without the four long large thoracic 

 spines, and the caudal horns on the eighth and ninth abdominal segments 

 of tlie previous stage. The genus appears to belong to the Ceratocam- 

 pidae. 



Although we are not yet acquainted with the early larval stages of En- 

 dromis, we do not see why the Sphingidse may not have sprung from a 

 form like this as much as from Aglia, as the shape and markings of the 

 full-grown caterpillar are much nearer a typical Sphinx than those of 

 Aglia. Moreover, taxonomically, Aglia is by no means so "closely" 

 allied to the Sphingidse as Mr. Poulton in his able papers would lead us to 

 infer. In its venation Endromis is much nearer, and the latter is a more 

 generalized or synthetic form than Aglia. From the Ceratocampidae the 

 families of Saturniidae and also of Hemileucidae may have originated, and 

 indeed all the Bombyces, unless we except the Arctians and Lithosidae, 

 may have evolved before the Sphingidae appeared. -ludging by the 

 characters of the head, the antennae, thorax, and especially the venation, 

 the Sphingidae are far removed from the Ceratocampidae, and their origin 

 from the latter family was at least remote, and tliere must be some lost, 

 extinct annectant forms which originally connected them. 



