132 Journal New York Entomological Society. [Voi. v. 
effect on the generic location of the species; it is probably the result 
of comparatively recent adaptation. 
Hyphantria cunea. 
Tubercles small, normal, two small areas detached from the cervical 
shield probably represent the two outer primitive setae. Setae all single 
as in S. virgmica , but on the thorax subprimary seta iii is situated on a 
small wart behind seta iv and on the abdomen subprimary vi is present 
on segments i to 8, small anteriorly, but of fair size further back. 
In this larva there is no precocious wart formation, but the subpri¬ 
mary setae appear in stage I almost perfectly formed (v is absent on 
thorax). According to my views, the Arctiidce are descended from the 
Noctuidce, , and here is a case where the specialization of the larva has 
crowded back into stage I the typical structures of the Noctuidce , the 
primitive first stage being absent, yet without the supervention of wart 
formation until stage II. 
Halisidota maculata. 
As in S. virginica , but for a doubling of setae iii on abdominal seg¬ 
ments i to 8 and the partial fusion of iv with iii. Subprimary tuber¬ 
cles absent. 
Here we have a partial precocious wart formation in the doubled 
setae on iii analogous to the condition in N. cintigone but considerably 
less developed, not affecting the thorax at all. I regard this species as 
more specialized than the preceding chiefly on account of the fusion of 
tubercles iv and iii, a condition found also in some of the Lymantriidae, 
a high type in another line of evolution. 
Halisidota caryae. 
Tubercle iv unconnected with iii, but iii doubled as in H. maculata. 
On segments i to 8 subprimary tubercle vi is present. No subprimaries 
on thorax, but iia partly fused with i on mesothorax; otherwise normal 
as in S. virginica. 
This larva exhibits a partial precocious wart formation and a partial 
appearance in stage I of the subprimary tubercles. It therefore shows 
an incompletely developed combination of the characters of Hyphantria 
cunea and Spilosoma antigone and is consequently higher than either. 
It is more advanced than H. maculata in the presence of the sub¬ 
primaries. 
Cosmosoma auge. 
Tubercles weak; setae single, normal, no subprimaries. This larva 
is placed higher than all the preceding on account of the complete 
