200 MEMOIRS OF THE NATIONAL ACADEMY OF SCIENCES. 



mark in my male, but a loug, slender, two-scalloped discal line, sending four black lines outward 

 along the veins. In the 9 a round, distinct discal dot. An outer, obscure, zigzag, double-sordid 

 white line, shaded externally with reddish brown, and indicated when obsolete by a double series 

 of short, longitudinal, black vcnular streaks. The venules beyond marked with black scales. 

 Fringe whitish, dusky toward the apex, and marked with dusky spots. Wings beneath, whitisli, 

 dusky on the costal region. 



Hind wings in S white, slightly dusky on the outer edge, and a dusky diffuse i)atch on the 

 internal angle. Abdomen iu both sexes olive whitish ash, becoming jialer toward the end, which, 

 iu my single male, is uot forked as usiaal in the genus. 



The 9 differs very much from the S , and is nuich more common in collections. The fore wings 

 are uniforndy of a peculiar stoue-ash or leaden gray, the basal aiul outer lines obsolete; a minute 

 black discal dot present. There is, as in the S , a broken black line at the base of the wing in the 

 submedian space. The outer edge of the wing is clear ash-gray. A series of longitudinal black, 

 sometimes red, wedge-shaped streaks just within the clear whiter marginal border, those opposite 

 the discal dot being the largest. 



Hind wings of 9 uniformly mouse-gray, with no distinct dusky patch near the internal angle. 

 Beneath, both wings uniformly dusky, becoming clearer, paler gray on the outer edge. Fore 

 wings with four pale marks on the outer third of the costa. 



Expanse of wings, S 30 mm., 9 3Gmm.; length of body, S 15mm., 9 l."i mm. 



Tliis species differs from S. ipomme, besides other points noted above, in the longitudinal black 

 streaks on the fore wings, in the absence of an inner line, in the linear black discal spot, and in 

 the peculiar white, frosty gray hue or ground color of the fore wings, there being no reddish or 

 brownish shades, except what is faintly shown in the extradiscal line. It differs from 8. unicornis 

 in the longer and more pointed fore wings and in the absence of reddish brown shades. From 

 both it differs in the peculiar black triangular mark on the thorax. The females are at once 

 recognized by the peculiar uniform leaden ash-gray ground color of the fore wings. 



E;i!/. — Transverse diametei', 1 mm., of the same size and shape as those of S. ipomea: Ilemi- 

 spherical, moderately high, and under a high Tolles lens seen to be very finely pitted; under a 

 half inch objective of Tolles the surface is seen to be divided into five and six-sided areas, with a 

 distinct raised edge; the surface smooth and more often with(uit the bead so common in eggs of 

 8^ ipomew. 



Toward and at the micropylar region the cells become longer, minuter, and more crowded, and 

 in this respect the egg seems to differ from those of 8. ipomea^ in which the areas are more or less 

 obsolete in the micropylar region. 



Freshly hatched larva. — Length, 3 mm. The head is very large, nearly twice as wide as the 

 body; deep honey-yellow. 



Prothoracic segment of the same tint as the head, but green behind. The rest of the body is 

 pale yellowish green, with rather large honey-yellow warts. The first and eighth abdominal 

 segments are deep cherry-red, while the sides of the second to seventh segments above the legs 

 are the same color. On the first and eighth segments is a pair of dorsal cherry-red tubercles, those 

 on the first somewhat larger than those on the eighth segment; those on segments 2 to 7 are small, 

 of nearly uniform size, and concolorous with the greenish yellow segments. The end of the body, 

 including the anal legs and the ninth and tenth segments, is upheld as usual in the geuus. The 

 thoracic and first four pairs of abdominal legs are dark. The anal legs smaller than those in front, 

 and are pale, being of the same color as the- end of the body. The glaiulnlar hairs are distinctly 

 seen to be bulbous at the tip and long and unequal in length, the two longest ones, i. e., those on 

 the prothoracic segment, being about three times as long as the body is thick. 



Compared with the larva of 8. ipomew of the same stage, the two dorsal warts on the 

 prothoracic segment appear to be a little smaller. The glandular hairs seen under a half inch 

 objective are of the same length and general shape as in 8. ipomea', but do uot appear to be (piite 

 so bulbous. ' 



' With the above description may be compared the following one drawn up from Riley's alcoholic specimens: 



Fimt stai/e. — Length, 4 mm. The larva of this 8taf;e is very similar to that of S. ipomeiv, the shape of the head, 

 of the tubercles, dorsal and lateral, and of the peculiar paddle-shaped glandular hairs being identical. I can only 



