MEMOIES OF THE XATIOXAL ACADEMY OF SCIENCES. 
139 
Expanse of wings, S , 30 inin.; lengtF of body, S , 14 imn. 
Tins not uncommon species differs from all the others in the distinct S-shaped portion of tl»e 
fourth or outer line, situated between the costal edge and the cubital vein, the outer curves of 
the S being lilled in with reddish brown. Also the basal line is not dislocated, both this and the 
second line crossing the entire wing and being parallel. 
Var. apecijiva Dyar. Under this name Dr. Dyar briefly mentions a form of this species 
captured at jManitou, Colo., May 2, “which differs from the ty[)e by its much paler (tolor.^^ 
Colorado (Fi-ench). 
Eg {/. — “Of a hemispheric form and dark brown, with a wide glaucous gray ring on the outer 
margin.” (Fitch, p. 275.) 
Larru.— The following description is drawn up from Mr. Bridghain's colored drawings of the 
thi'ee last stages an<l an alcoholic specimen of the mature larva. It occurred on the iioplar, d nly 9 
to 13, those in the three last stages occurring at these dates. Other specimens were reared by 
Mr. Bridgham and the moths obtaim*d from them. (For stage II see Appendix A.) 
Larva in Stage 111. — Lengtli, 20 mm. Head as wide as the bod}’, reddish. The body reddish 
on the sides, and green along the back, interrupted by a reddish patch on the first and one on the 
eighth abdominal segments, each of which incloses a median tubercle. The green back incloses 
three parallel dark green, indistinct, interrupted lines. There are two greenish tubercles on the 
side of the body, one above and the other below the siiiracle. 
Stage IV, — Length, 30. mm. The hair is still reddish, but the body has now lost its green 
shade on the back, which is jiale, with three darker pai*allel dorsal lines. The two median 
tubercles are now as well developed as in the last stage. The side of the body is pale reddi.sh, 
with dark lateral tubercles on the thoracic and first abdominal segments, those on the succeeding 
segments being yellowish, as on the abdominal legs, including the anal jiair and suranal plate. 
The thoracic legs are pale. 
Full-fed larva. — Length, 30 mm. Head hardly as wide as the body, black, with a y-shaped, 
pale browm line in front, formed of a median line extending down from the vertex to tlie apex of the 
ciypeus, and then dividing so as to extend down on each side, ending before reaching the antenna*. 
The head is fattened and densely covered with grayish hairs. The three thoracic segments bear 
each six lateral, rather large, yellowish warts, the lowest one the largest, ea ii bearing about six or 
seven hairs of unequal length. There is a high median linger-shaped, fleshy nutant black tubercle 
on the first abdominal .segment, bearing numerous short, une<|ual hairs; it is rather high, linger- 
shaped, and bent over backw'ard. On the eighth segment is a shorter, smaller, iialer one. It is 
evidently of double origin, its longest diameter being transverse to the body, and somewhat 
wedge-shaped; the end is somew'hat swollen on each side, with a slight valley betw^een the 
sw’ellings, showing that it wms originally formed of tw'o separate tubercles, and this is also 
suggested by the fact that each sw'elling bears eight or ten short unequal hairs. The thoracic legs 
are black; the abdominal legs are dark, especially toward the plaiita. 
Colors (described from Bridgham’s figure): Body straw’-yellow, with three dorsal, more or less 
interrupted grayish or pearly pale browm lines and a broad lateral stripe, below which the 
tubercles are yellow^ ocherous. The suranal plate is flattened, rounded in outline, and hairy, with 
the surface rather rough and hairy. In my single alcoholic specimen there is no sign of a 
prothoracic slweld or i)late. 
Although the imago of I. aplealis- is very near that of J. ineima in markings, the larva is very 
different, there being no median dorsal tubercle on the first abdominal segment. In the lack of 
these tuber(*les I. strigosa resembles J. apiealis. On the other hand, the larva of I. albosigma, in 
respect to the presence of the two dorsal abdominal tubercles, appi’oaches that of I. ineluHa. 
These two species, then, as larvm. belong to the same genus, wdiile the tAvo other species (apicaJis and 
5/r/V/o,va), as resi>ects the larva*, differ generically I'rom inclusa and albosigma^ tiiongli the moths 
are congeneric. It is eviden t that the larva of apiealis and strigom are more generalized, since they 
lack the rather highly specialized dorsal tubercles so prominent in the tw'o other species of the 
genus. If we regarde<l the moths alone we might erroneously consider that apiealis and inclusa were 
both coeval, Avhereas apiealis must be a mucli older, more generalized form; hence, specidations on 
the phylogeny of Lepidoptera based on the imagines alone may often be uncertain. 
