640 The American Naturalist. [July, 
The metathorax is but little shorter and smaller than the 
mesothorax, and remarkable for the widely separated halves of 
the scutum, a Neuropterous character (compare Ascalaphus and 
Corydalus) in which it differs from Micropteryx. The slope of 
the scutellum is that of a low, flattened triangle. 
As regards the abdomen, attention should be called to the 
disparity in size and shape between the sexes, also to the male 
genital armature, which is very large and completely exserted: 
and reminds us of that of Corydalus, in which, however, the 
lateral claspers are much reduced, and also that of certain 
Trichoptera (Sericostoma, Tinodes, Stenophylax, Hydropsyche, 
etc.). 
The larval characters of this sub-order it would be difficult 
to give, for in the remarkable larva of Hriocephala calthella as 
described and figured in Dr. Chapman’s elaborate account, we 
appear to have a highly modified form, entirely unlike the 
simple apodous larva of Micropteryx, and perhaps quite un- 
like the primitive stem-form of Lepidopterous larve. We are 
indebted to Dr. Chapman for mounted specimens in a slide 
kindly given us by him. The body is broad and flattened, the 
segments very short in proportion to their width, the prothor- 
acic segment, however, very long in proportion to the others, 
but the surface rough and corrugated, not with a hard, smooth 
dorsal plate as in many Tinide, Tortricide, ete., since it is not 
a boring insect. The eight pairs of abdominal prop-like tuber- 
cles, which we should hardly regard as homologues of the 
abdominal legs, are, like those of the Panorpide, simple tuber- 
cles armed with a curved spine. The tenth or last abdominal 
segment is armed with a pair of dorsal spines, arising from a 
tubercle. The singular flattened and fluted sete represented 
by Chapman are unique in Lepidopterous larve. He also de- 
scribes a trefoil-shaped sucker on the under side of the ninth 
and tenth abdominal segments, “ very unusual;” though as it 
appears to be paired, it does not, as Chapman thinks, seem to 
us to indicate “a further point of relationship to Limacodids.” 
Chapman states that “the head is retractile, so far, that it 
may occupy the interior of the second thoracic segment,” 
and he says that “the antenne are remarkably long for a 
