Packard.] 
112 
[May 7, 
After haying become familiar with the freshly-hatched larvae of 
some of the more t} T pical genera of the leading groups of the su- 
per family Bombyces, as we may regard it, and seeing how the}' all 
differ from the freshly-hatched larvae of the Noctuidae and G-eomet- 
rids (about which, however, our knowledge is very scanty) we ex- 
amined the excellent figures by Mr. Emerton in Scudder’ s elaborate 
and exquisitely illustrated work on the Butterflies of the Eastern 
United states, representing the early stages of species of all the 
different families. We were at once struck with the fact that in 
their first stages butterflies in general show a decided resemblance 
to Bombyces of the same age, so much so as to suggest that they 
have possibly descended from the silkworm moths. Jt seems to 
us pretty well established that the Sphingidae, together with the 
closely associated Thyridae and Sesiidae have descended either from 
the Ceratocampulae or from extinct forms closely resembling them. 
The Zygaenidae and Arctiidae have undoubtedly had a common 
origin unless the former have directly evolved from the Arctians, 
and therefore the Bombyces may be looked upon as an ancestral 
or phylum -generating group. 
If we examine the freshly hatched larva of the different species 
of Papilio figured by Scudder they will be seen to bear a remarka- 
ble resemblance to the Attaci (Saturnidae) in the same stage, as, 
for example, Telea polyphemus. The body is tuberculated in much 
the same manner, the tubercles being the largest on the prothora- 
cic segment and on the eighth and ninth abdominal segments. In 
P. troilus , stages i and n, there is a striking similarity in shape 
and in the mode of arrangement of the spinulated tubercles. There 
is a pair of elongated dorsal spinulated tubercles on the prothoracic 
and eighth uromere (abdominal segment) ; and it may be said in 
passing that there is also a similarity in shape, in the lateral line 
and in the terrifying eye-spots, to the mature larva of Aglia tau of 
Europe. So also the transverse black bands and stripes of the fully 
fed Papilio polyxenes recall the mature larva of the European Sa- 
turnia. The freshly hatched larvae of Papilio polyxenes and cres- 
phontes though they have glandular hairs, and also Papilio ajax , 
which has two sub-dorsal tubercles projecting laterally, with the 
tubercles on the second thoracic to the seventh abdominal segments 
bearing forked spines, recall the Attacid larvae. 
These facts are certainly suggestive. It should be observed that 
none of the freshly hatched larvae figured by Scudder appear to 
have a single median dorsal tubercle or spine on the eighth abdom- 
