THE AMERICAN ENTOMOLOGIST. 



151 



may often be found in the latitude of St. Louis 

 as early as the beginning of May, and more 

 abundantly in June, while scattering individuals 

 (probably of a second brood) are even met with, 

 but half-grown, in the month of September. 

 The young larvas are whitish with brown trans- 

 verse lines, the colors not contrasting so strongly 

 as in the full-grown specimens, though the black 

 spots are more conspicuous. They feed beneath 

 the leaves and can let themselves down by a 

 web. The full-grown larva often conceals itself 

 within a folded leaf. It is of the form of our 

 figure, and is marked transversely with white 

 and black lines, each segment having about 

 eight light and eight dark ones. The bluish 

 appearance of this caterpillar is owing to an 

 optical phenomenon from the contrast of these 

 white and black stripes. The head and the 

 shield on the first segment are of a shiny bright 

 deep orange color, marked with black dots, 

 and there is a prominent transverse orange- 

 red band, faint on segments 2 and 3, conspicu- 

 ous on 4 and 11, and uniform in the middle 

 of each of the other segments. In the middle 

 segments of the body each orange band con- 

 tains eight black elevated spots, each spot 

 giving rise to a white hair. These spots are 

 arranged as in the enlarged section shown in 

 the engraving (Fig. lOt), b), namely, four on each 

 side as follows: the upper one on the anterior 

 border of the orange band, the second on its 

 posterior border, the third just above spiracles 

 on its anterior border — each of the three inter- 

 rupting one of the transverse black lines — and 

 the fourth, which is smaller, just behind the 

 spiracles. The venter is black, slightly varie- 

 gated with bluish-white, and with the orange 

 band extending on the legless segments. The 

 legs are black, and the false legs have two black 

 spots on an orange ground, at their outer base; 

 but the characteristic feature, which especially 

 distinguishes it from the other two species, is 

 a lateral white wavy band — obsolete on the 

 thoracic segments, and most conspicuous on 10 

 and 11— running just below the spiracles, and 

 interrupted by the transverse orange band.* 



•We quote here Harris's full description of this larva 

 (Correspondenct, p. 2Sii) , as it agrees with ours, except in 

 giving the number of transverse black lines as B on each 

 segment, instead of 8, from the fact that he does not include 

 the two which hurder the orange banil, on account of their 

 being interruiiled. We have preferred to consider each 

 segment of this worm as 8-banded, to distinguish it more 

 readily from tlie other tTo species, wliich have respectively 

 onlv SIX and four: "Length, when at rest, one inch and iwo- 

 teuths, very pale blue, transversely banded with orange 

 on the middle of each segment, the bands dotted with 

 small black points, producing hairs, and Burinounted by 

 black lines, and between each of the bauds six transverse 

 black lines. A large, iriegular, white spot on the side of 

 thj; tenth and eleventh segments, and a series of smaller 

 white spots on each of the other segments except the Urst 

 three. Head orange dotted with black. Legs blacki^h ex- 



This larva transforms to chrysalis within a 

 very slight cocoon formed without silk, upon, 

 or just below, the surface of the earth, and issues 

 soon after, as a very beautiful moth of a deep 

 blue-black color, with orange shanks, yellow 

 shoulder-pieces, each of the front wings with 

 two large light yellow spots, and each of the 

 hind wings with two white ones. Our illustra- 

 tion (Fig. 100, c) represents the female, and the 

 male diflers from her iu having the wing spots 

 larger, and in having a conspicuous white mark 

 along the top of his narrower abdomen. 



We have on one or two occasions known 

 vines to be partly defoliated by this species, but 

 never knew it to be quite so destructive as it 

 is represented in the following communication 

 from Mr. W. V. Andrews, of New York city, 

 wliich we take from the February (18fii>) num- 

 ber of the American ]}fati<ralint : 



"That a man should desire to raise his own 

 Isabellas is laudable and praiseworthy; and I 

 see no reason why such desire should exist 

 exclusively in the breasts of our bucolic friends. 

 The inhabitants of New York, as a general 

 thing, clearly are of the same opinion, as is 

 evidenced by the number of grape-vines orna- 

 menting the doors and trellis-work of ihe houses 

 of our citizens; not, of course, in the benighted 

 regions of Wall street, but up-town; sa\- from 

 Sixteenth street, northward. A friend of mine 

 residing on Thirty-fourth street, shov^ed nie, in 

 March last, a very fine vine, which he calculated 

 would produce him sundry pounds of very 

 choice grapes, and in the i)ride of his heart ha 

 invited me to '-call along" occasionally, and 

 feast my eyes on the grudnal development of 

 the incipient bunches. Thinking that August 

 would be a good month for my visit, I " called 

 along," wondering in ray mind whether my 

 friend would, when the time of ripe grapes came, 

 desire me to help myself out of his abundance; 

 or whether he intended to surprise me with a 

 little basket of nice bunches, garnished with 

 crisp, green leaves. The first glance at the 

 grape-vine banished all doubts on this point. 

 There were an abundance of bunches on the 

 vine, in a rather immature condition, of coarse, 

 but of foliage there was not a trace. Of course 

 I expressed my surprise, though, for certain 



temally. The full-grown have a decidedly bluish tinge, 

 entirely owing, however, to an optical phenomenon h'ura 

 the contrast of the white with the transverse black lines. 

 The head is of a pale dirty orange or rusty yellow, with about 

 eight black dots on each side; a semicircular plate on the 

 top of Ihe lirSt segment and the anal valves are pale orange 

 dotted with black. There is atrausverse series of black dots 

 on the second aid third segments, without an orange band. 

 Each of the other segments is transversely banded « ith 

 orange and dotted with black; the dots being in two alter- 

 nate rows, and all of them emitting distmct, long, whlll^h 

 hairs. Between each .if the bands there are six slender, 

 continuous, black transverse lines. The points are aloo con- 

 nected by interrupted black lines. Legs at base orange, 

 black externally and at tip, except the anal pair whii-h sre 

 orange, dotted with black The larg- w Int.- lateral ^p..t is 

 common to the side of the tenth ami eleventh se'.'iu.ius. 'I he 

 other lateral white spots are situated iiiniu'dialely liehind 

 the hands on the fourth, fifth, sixth, seventh, eighth and 

 ninth segments, the anterior spots being largest; ami Iheiiee 

 thev diiiiinish tii the ninth, while again the posterior spot 

 i> very large and very distinct The orange bands are inter- 

 rupted on the top of the seventh, eighth and ninth segments. ' ' 



