1890 .] 
559 
[Packard. 
6. Back 2-8-liumped, serrate, body smooth, not brightly striped. 
Notodonta , Nerice. 
7. Body smooth, gayly striped, eighth abdominal segment gib- 
bous. Edema , Dasylophia. 
8. Body with stout spines and with spiny tubercles on first and 
eighth abdominal segments. (Edemasia . 
9. Body smooth, with nutant tubercles on first and eighth ab- 
dominal segments ; end of body uplifted. Colors green with brown 
patches simulating dead blotches on leaves. Hyparpax , Schizura , 
and Janassa. 
10. Body smooth, tapering ; anal legs normal, with two protho- 
racic tubercles, enormous in early stages. Cecrita guttivitta. 
11. Body smooth, striped ; anal legs normal. Lochmceus manteo. 
12. Body with two dorsal prothoracic tubercles ; anal legs flla- 
mental ; each ending in an eversible flagellum. Heterocampa mar- 
thesia. 
13. Body with two lateral prothoracic tubercles; anal legs fila- 
mental, each ending in an eversible flagellum. Centra. 
14. Body doubly humped on the abdominal segments ; filamental 
anal legs. The Old World genus Stauropus. 
So far as I have gone in the examination of the structure of the 
moths, this succession of genera roughly corresponds with the usual 
classification of the famity. Judging by the moths alone, Ichthy- 
ura with Datana stands at one end of the series and Cerura at 
the other. 
Perhaps Cerura has generally been placed at the end of the group 
because of its fancied resemblance to the larva of Drepana, but this 
is deceptive, because the long caudal filament of the latter genus 
is simply a hypertrophy of the suranal plate, and the anal legs 
themselves are atrophied, while in Cerura they are enormously hy- 
pertrophied, probably owing to their active use as deterrent ap- 
pendages. 
SUMMARY. 
One would suppose that the two genera Nadata and Lophodonta, 
with the Old World genera Pterostoma, Ptilophora, Drymonia, 
Microdonta, and Lophopteryx 1 (of the two species L. cucullina 
!The first larval stages of the following genera are still unknown and the author 
would be much indebted for eggs or alcoholic specimens ol the larvae of the first and 
later stages Ellida, Nadata, Lophodonta, Gluphisia, Hyparpax, Pheosia, Notodonta, 
(Edemasia, Nerice, Janassa, Lochmaeus, and Heterocampa. 
