44 INSECTS INJURIOUS TO FOREST AND SHADE TREES. 
Gastropacha never associate upon the same tree, and I think that the former has 
always the mastery. This is perhaps owing to some excretion from its body which is 
unpleasant to the Gastropacha ; but of course I do not speak with certainty as to this 
fact. It is, however, sure that they are never found in large quantities on the same 
tree. I am inclined to think that Phryganidea 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 
eges of Phryganidea. 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 larve 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 
base; body pale canary-yellow, with four rows of black spots arranged longitudi- 
nally in lines. 
The larva is slender, with the head prominent, globose; last segment but one 
humped; head pale brown; body black above, dirty green below, with a broad dorsal 
line of dirty greenish, divided by three narrow black lines, and the sutures faintly 
marked with same color. There is also a narrow, broken, stigmatal line of dirty 
greenish, and a similar line above each of the abdominal legs. Tip of the last seg- 
ment horny, the segment not being used to assist in progression, but usually slightly 
elevated; body smooth, transversely wrinkled. Younger specimens chiefly differ in 
the disproportionate size of the head. Length 0.90 to 1.00 inch. 
Pupa, naked, suspended by the tail, greenish white, with black markings; all the 
sutures of the head, thorax, legs, and antenn lined with black. The mesothorax has 
a central black line; the abdomen has a dorsal row of black points on the front edge 
of each segment, and a lateral row blending into each other towards the anal seg- 
ment, which is black; below with two sublateral series of black transverse spots 
nearly blending into two longitudinal bands. Length 0.75 inch. (Stretch.) 
Mr. Behrens, of San Francisco, writes me that three generations of 
the Phryganidea appear in a year. “In 1875 it, with the larva of the 
Gastropacha californica, ate our evergreen oaks to broomsticks. You 
could hear the caterpillars eat and their manure drop, the latter cover- 
ing everything; it could be swept together by the bushelful. In the 
wake of both followed ichneumon parasites.” 
This singular insect was originally, from a study of the moth alone 
referred by me to the Psychine, but Mr. R.H. Stretch, with a knowledge 
of its transformations, has shown that I was in error, and has placed it 
very properly in the Zygaenide, in his valuable work entitled ‘ Illus- 
trations of the Zygaenide and Bombycide of North America” (1873). 
Having recently received specimens of the larvee and pup from Mr: 
James Behrens, it was atonce evident on a cursory examination that the 
early stages show all the characteristic features of Alypia and Eudryas 
and the other higher members of the Zygaenide. The venation of the 
moth is, however, aberrant, and this together with the dull-brown color- 
ation and semi-hyaline wings misled me into placing it near Psyche. 
