WILLOW-GALL TIXEIDS. 583 
rhodoides Walsh. This is the insect that I think I mentioned to yon as being very 
prettily marked in the larval state, each segment having a broad black band, and 
the ground color being whitish. I had a single oue come out last summer, but the 
great bulk of thein hybernated either in the larva or pupa state and came out May 3 to 
•20. They vary but little. I have beaten larva- of very similar appearance off oak 
trees. 
So far as I am informed the larva is unknown to European Lepidop- 
terists, although it is recorded that the perfect insect, prceangusta, is 
very common among willows and poplars in July, and may frequently 
be observed sitting on the trunks of those trees with the anterior feet 
put back like Bdellia and the head raised a little. 
Mr. Walsh has the honor of having made an interesting discovery 
that puts an end to all uncertainty respecting the larva and its food- 
plant. 
This larva occurred in abundance August 23, and subsequently in the Tenthredi- 
nidous gall, S. pomum, Walsh manuscript, which grows on the leaves of Satis cor- 
data. Each gall contained but a single larva, unaccompanied by the larva of the 
Sematus which makes the gall, which it must consequently have destroyed or starved 
out, either in the egg or in the larva state. 
A single imago came out in the autumn of the same year, but the great bulk of 
them came out next spring, May 6 to 20, from galls kept through the winter. There 
can be no doubt of the correlation of larva and imago, because no other Lepidoptei ous 
larva or imago occurred in the gall S. pomum, though I had three or four hundred of 
them in my breeding vase. The insect must hibernate normally in the larva state, 
for I noticed numbers of them in the spring crawling about among the galls. In a 
state of confinement it generally retires to the inside of the gall to assume the pupa 
state, though I noticed one or two cocoons spun among the galls. Probably in a 
state of nature it hybernates in the gall, comes out of it in the spring, and spins its 
cocoons among dry leaves and rubbish. 
I also bred a single imago of this same species, May 11, from the Cecidomyidous 
gall, S. rhodoides, Walsh, from galls kept through the winter, and I found in the 
spring a denuded imago of what was apparently the same species, dead and dry 
amongst a lot of Tenthredinidous galls, S. desmodiodes, Walsh manuscript, which is 
olosely allied to S. pomum, but occurs on the leaves of a very distinct species of willow. 
Thus we have three different willow galls inhabited by the same moth, two of them 
made by saw-nies and one by a gall-gnat. 
I have several times beaten off black-oak trees larva? apparently very similar to 
this Batraehedra, and with the same harlequin-like markings, but whether the two 
are specifically identical I can not say. 
In a subsequent letter Mr. Walsh kindly supplied me with the fol- 
lowing description of the larva : 
Larva. — Length, .20 inch. Body tapering at each end, opaque, milky-whitish, 
with a few short, whitish hairs. The first segment behind the head with an obseini- 
circular, shining, glabrous, brown dorsal shield; second segment with an interrupted 
opaque brown dorsal band on its anterior edge, the interruption occupying about 
one-third of the baud; segments 3 to 12 with an interrupted opaque brown dorsal 
band on the anterior edge, and segment 11 with a similar band at its tip also. 
Head yellowish. Legs and venter immaculate whitish. Legs six, prolegs ten, nor- 
mally arranged. Spins a thread, wriggles much when disturbed, and runs backward 
with great agility. (Clemens' Tineina. Edited by H. T. Stainton.) 
Moth. — Forewings fuscous, with a rather broad whitish stripe, freely dusted with 
fuscous, ruuning through the middle of the wing from the base and along the apical 
