122 FIFTH REPORT OF THE ENTOMOLOGICAL COMMISSION. 
166. Tin: A.mkkicax i.ai'I'kt-moth. 
Qaatropacha amerieana Harris. 
Order Lepidoptkra ; family Bombycidjt:. 
The interesting larva of this moth rarely occurs on the oak. 
Larva.— Body broad, somewhat flattened; the lateral ridge produced on eaeh seg- 
ment into a pail of hairy lappets, white, edged with gray, and Cringed with lung radi- 
ating hairs. On the eighth abdominal segment is a round Mack hamp ringed with 
white. The body is white and gray, mottled so as to resemble the pale bark of the 
ash or poplar. When creeping two transverse bright scarlet bands are disclosed in 
the siit in. s just behind the second and third thoracic segments. On each segment 
are two dorsal, curved spindle-shaped dark gray spots: the sides are clouded with 
dark gray. Length :>:>-<;()""". 
167. The Califobnian phkyganidia. 
Phryganidia califomica Pack. 
Order Lepidoptbra ; family Zyqmmdm. 
Very destructive to young oaks, a naked, yellowish-white caterpillar, striped with 
black and white, with a large head, wandering incessantly over the bnshesaad feed- 
ing very rapidly ; spinning no cocoon, but the chrysalis, yellowish and black, attached 
by the tail to fences, &c. 
This is, by its numbers and familiar habits, one of the best known 
and most destructive insects of California. The following accouut has 
been furnished me for Hayden's Report by Mr. Henry Edwards:* 
"This insect is also very destructive to our young oaks, the caterpillars, which are 
naked perfectly and with the head almost monstrous in size, making their appearance 
about the same time as those of Clisiocampa. They are 
restless little creatures, wandering incessantly over the 
trees and feeding very rapidly. They spin no cocoon, 
but hang by the tail, like the larva of Vanessa, etc. The 
change to the chrysalis is undergone in April and May, 
and the moths appear in about fifteen or sixteen days. 
There is a second brood of these insects, the imagos of 
Fig. 38.-Caliibrnian Phrygani- the laUer appearing in September and October. Indeed, 
<lia. — From Packard, after „ , ,, ., , ., 
_ fresh specimens are now upontr.e wing, though the sec- 
ond brood is by no means so abundant as the first. I have 
observed that Phryganidia and Clisiocampa never associate upon the same tree, and 
I think that the former has always the mastery. This is perhaps owing to some ex- 
cretion from its body which is unpleasant to the Clisiocampa, but of course I do not 
speak with certainty as to this fact. It is, how r ever, sure that they are never found 
in large quantities on the same tree. I am inclined to think that Phryganidia is more 
destructive to the oaks than the other species, as it feeds solely upon Quercus, while 
the other, as I have said, is not so particular in the choice of its food. I inclose my 
published description of the eggs of Phryganidia.'' I quote Mr. Edwards's description 
of the egg and larva: 
" The egg is spherical, a little flattened above, shining, yellowish-white at exclusion, 
attached in clusters of about ten or twelve to the upper sides of the leaves. The 
third day the apex of the egg assumes a dull orange hue, afterwards changing to a 
bright reddish-purple and gradually to a duller shade as the young larva emerge. 
The eggs were laid by a female in my possession on July 5. In the young larva the 
head is very large, almost monstrous, pale olive-brown, with a narrow black line at 
basr ; body pale canary-yellow, with four rows of black spots arranged longitudi- 
nally in lines. 
* A. S. Packard, jr., Report on the Pocky Mountain Locust, *Vc. Hayden's Report 
U. S. Geological Survey of the Territories for 1876. 
