1890. J 
553 
[Packard. 
spraying apparatus lodged in the first segment next to the head 
seems to function in undiminislied vigor. Experiments like those 
made by Mr. Poulton, on the fluid secreted by Cerura, should be 
conducted with the present insect. 
2. The second point is the complete reduction in size of the two 
high prothoracic spine-like tubercles, which takes place at the last 
exuviation. 
3. The head compared with that of Cerura is not retractile, the 
prothoracic segment being of the normal size. 
From what we now know of the larvae of the genus Heterocampa 
of G rote’s catalogue, the species whose larvae are known may be 
grouped into the following order, though it may be found when 
we know more of the first three species, that guttivitta should be 
assigned to a separate genus (Cecrita of Walker). 
f astarte. 
Group I. \ ° bUq Z .. 
j trouvelota. 
(j guttivitta . 
t manteo. 
\ pulverea. 
III. 
j unicolor. 
\ marthesia. 
Whether these divisions correspond to generic groups remains 
to be seen after further examination of the imaginal characters. 
LIFE-HISTORY OF CERURA BOREALIS BOISD. 
The following account of the ontogeny of this species (identified 
from Professor French’s description) has been drawn up in part 
from alcoholic specimens and in part from greatly enlarged and 
most carefully executed drawings by Mr. J. Bridgham. The dif- 
ferent stages occurred at Providence on the wild cherry in Septem- 
ber. Hellins states that the eggs of C. vinula are 1.6 to almost 2 
mm. in diameter, and that. the larva at its first moult is not more 
than 7 mm. long. Possibly the first stage was not observed by Mr: 
Bridgham, and the following description should apply to the sec- 
ond. 
First stage . — Length in all 15 mm. Sept. 4. Head only as wide 
as the body behind the middle. The filamental anal legs, or stem- 
