780 
Journal of Agricultural Research 
Vol. XXX, No. 8 
fail to reveal that they afford attach¬ 
ment for body muscles, cutaneous or 
others. It is true that they are feebly 
chitinized, thinner in fact than other 
portions of the integument, but this is 
apparently due in large measure to the 
absence of the characteristic skin 
granules present elsewhere on the dor¬ 
sum. 
Heinrich uses the anterior epicranial 
setal group (11) and puncture to sep¬ 
arate nubilalis from ainsliei. This 
unquestionably is a good character, 
and is, as a matter of fact, the only 
reliable character that can be used to 
separate the two species in all larval 
stages (see P. ainsliei below) (pi. 2, 
I and J). 
PYRAUSTA AINSLIEI HEINRICH 
Pyrausta ainsliei Heinr. 1919, Jour. Agr. Re 
search 18:175, pis. 7-lo. 
Pyrausta penitalis auct. (nec Grote). 
After a careful comparison of the 
genitalia of the specimens of Pyrausta 
penitalis Grote in the National Museum 
and after a further examination of 
Grote’s types of the same species in 
the American Museum of Natural 
History in New York, Heinrich was 
convinced that two species were in¬ 
volved and confused with each other 
under the specific name penitalis. Ac¬ 
cordingly, he separated this species and 
described it as ainsliei from specimens 
furnished him by George G. Ainslie 
of the Bureau of Entomology, Knox¬ 
ville, Tenn. 
In 1920 Flint and Malloch treated a 
lepidopterous larva occurring in smart- 
weed as Lederer’s obumbratalis (8, p. 
303-304 ). Heinrich (12, p. 57) es¬ 
tablished the identity of this species 
as ainsliei , admitting the possible 
synonymy but calling attention to the 
impossibility of fixing the actual iden¬ 
tity of obumbratalis at the present 
time. To avoid confusion and pos¬ 
sibly misapplication of a name, it is 
advisable at present to use ainsliei 
rather than obumbratalis as the designa¬ 
tion for our smartweed borer. 
The larvae of Pyrausta ainsliei 
have been found in all stages of de¬ 
velopment in eastern Massachusetts in 
the following plants: Polygonum penn- 
sylvanicum L. var. laevigatum Fernald, 
P. lapathifolium L., P. persicaria L. 
(smartweeds); Xanthium sp. (cockle- 
bur) ; Ambrosia artemisiaefolia L. (rag¬ 
weed); Eupatorium sp.? (Joe-pve 
weed); Apocynum androsaemifolium L. 
(spreading dogbane); Typha latifolia 
L. (cat-tail); Chenopodium album L. 
(Iambus-quarters). Adults have been 
bred through from second instar larvae 
from all these plants with the exception 
of Apocynum and Chenopodium. In 
these two cases very young larvae were 
taken from these plants in the field but 
failed to live in confinement. By 
subsequent visits to plants infested in 
the field, however, the writer was 
convinced that the species was develop¬ 
ing therein. It should be stated in 
this connection that instances of larvae 
developing in plants other than Polyg¬ 
onum pennsylvanicum L., and P. 
lapathifolium L., were infrequent; so 
that it became apparent that the 
species greatly prefers the smartweed 
group of plants in which to breed. 
In the late autumn larvae have been 
taken from the following shelter plants: 
Rubus sp.?; Sambucus canadensis L. 
Zea mays (corn), Solidago canadensis 
L., Echinochloa crusgalli (L.) Beau, 
(barnyard grass), Bidens frondosa L. 
(beggar-ticks); Typha latifolia L., Apo¬ 
cynum androsaemifolium L. In No¬ 
vember Vickery sent a lot of cotton 
plants collected at Wilmington, N. C., 
February 11, 1921, to the Arlington, 
Mass., laboratory, from which many 
larvae of Pyrausta ainsliei were cut. 
Cotton is probably a shelter plant. 
Ainslie and Cartwright published 
some results obtained on the biology 
of ainsliei in which they list (1, p. 838) 
the following as reported natural food 
plants: Polygonum pennsylvanicum 
(var. not given), P. lapathifolium, P. 
persicaria, P. hydropiperoides. They 
also reared the larvae in confinement 
EXPLANATORY LEGEND FOR PLATE 2 
LARVAL DETAILS 
A. —Setal map of Pyrausta nubilalis, prothoraeic, mesothoracic, and third, eighth, and ninth abdomina 
segments of larva. (After Heinrich) 
B. —Setal map of Phlyctaenia rubigalis , prothoraeic, mesothoracic, and third abdominal segments 
C. —Setal map of Diatraea zeacolella, mesothoracic and ninth abdominal segments. (14, pi- 4) 
D. —Setal map of Depressaria heracliana, prothoraeic and eighth and ninth abdominal segments 
E. —Setal map of Loxostege similalis, third and ninth abdominal segments 
F. —Setal map of Nomophila noctuella, prothoraeic, mesothoracic, and third, eighth, and ninth abdominal 
segments 
G. — Epiblema scudderiana: Setal map of prothorax 
H. — Heliothis obsoleta: Setal map of third abdominal segment 
I. — Pyrausta nubilalis: Cephalic view, left half of head 
•T.— P. ainsliei: Cephalic view, left half of head capsule 
K. — P. nubilalis: Crochets on plan turn of pseudopodium 
L. — Epiblema scudderiana: Crochets on plantum of pseudopodium 
M. — Heliothis obsoleta: Crochets on plantum of pseudopodium. (After Heinrich) 
