fi-AS [December 



Sesia Thysbe Fabr. 



Larva. 1.75 in. long, .28 in. broad. Head elliptical, granulated, dull 

 green; when at rest, partially buried within the first segment. Mandi- 

 bles yellow, black tipped. Body tapering anteriorly from the seventh 

 segment, clear green, lighter dorsally, shading darker to the stigmata, 

 below which to the prolegs it is of a uniform darker hue; underneath, 

 from the third pair of legs to the terminal pair, dull rose, bordered ex- 

 ternally by a buff stripe, continued to the sixth segment, and inflated 

 above the prolegs. First segment carinated on its antei-ior margin su- 

 periorly, upon which are about sixteen light yellow granulations. Col- 

 lar studded with smaller light green granulations. Vascular stripe, 

 bordered by two white lines, commencing on the second segment, be- 

 coming wider and more distinct on the central segments, and uniting 

 anterior to the base of the caudal horn. A white, sometimes yellow- 

 green subdorsal line, commencing on the second segment, running 

 midway between the stigmata and dorsum, and terminating in the .sides 

 of the caudal horn, made up of a white spot on each annulation. except 

 on the smooth eleventh segment, where it is continuous ; white ocella- 

 tions on the annulations ab)ve the stigmata. Stigmata red, with a 

 white dot at each extremity. Caudal horn, .2 in. long, curved lio-ht 

 blue, yellow tipped, granulated with white laterally, with black anteri- 

 orly, and a few black granulations posteriorly. Caudal shield and 

 plates granulated like the collar. Legs, basal joint black, tips red. 

 Prolegs green, with a fusiform black spot exteriorly. 



Feeds on the 8now-ball ( Viburmnn opului<) (\\\r\n<>; the last of Auoust 

 and first of September. For the knowledge of the food-plant of this 

 larva I am indebted to Mr. Gregg Johnson, of this city, who informs 

 me that for several years he has found it to be quite common, several 

 usually occurring on the same shrub. 



Its readiness for pupation is indicated by a marked change of color, 

 noticeable about twenty-four hours before it commences the construc- 

 tion of its imperfect cocoon, which is composed merely of a few leaves 

 drawn together by a very slight spinning, and placed in an angle of 

 the box in which it is confined. Its head changes to purple ; the "ra- 

 nulations of the first segment, ochre-yellow; between the sub-dorsal 

 lines, purple or reddish-brown ; laterally and ventrally, pea green. 



