MEMOIRS OF THE NATIO^■AL ACADEMY OF SCIENCES. 31 



Armatin't. -^Thi" prothoracic plate large, occupying the entire length of the segment, with 

 four dorsal glandular setse (/, //) and two subdorsal setre (tubercle v), a double one, /. /,>., one 

 with two setip, directly in front of the spiracle, and two separate ones (rt\ v/'/') at the base 

 of the leg, this arrangement tieing the same in all the thoracic segments. 



The second thoracic is considerably longer than the third thoracic segment, the anterior 

 half forming on each side a distinct swollen, smooth boss, which in the succeeding stage becomes 

 one of the four false spines or *■" horns"; directlj' behind on each side of the median line is a 

 tubercle or boss sending off two glandular hairs (i, a, PI. XLII, tig. 1); each boss is at the end of a 

 transverse ridge. The thii'd .segment repeats the .same characteristics, but the smooth bosses are 

 lower and smaller. It is thus seen that already in this stage the " horns" of this sphingid larva 

 are in no way homologous with the horns of the Ceratocampidre, which are specializations of 

 the first dor.sal tubercles (/). These bo.sses or false tubercles become a little more prominent at 

 the end of the stage. 



On each abdominal segment one to seven, the four dorsal tubercles (/', //), are arranged in 

 a trapezoid, as in nearly all primitive larva?. 



On the side is a subdorsal series (///), and directly below the spiracle tubercle iv; while in 

 front of each spiracle is tubercle v; tubercle iv is situated in a line vertical!}' with m, and mid- 

 way between it and the end of the mid-abdominal legs, /. <., just above the base of each of these 

 legs. On the apodous abdominal segments one and two are tubercles vi and vii (regarded by 

 Dyar as representing tubercle /v'), which are rather far apart from each other. 



The glandular hairs are all of uniform length and shape, being a little stouter than the other 

 seta? and enlarged or bulbous at the end. Those of the dorsal series (/, //), are much more 

 bulbous at the end than those of the sides (///-?v'/). 



There are none on the eighth, ninth, and tenth segments with bulbous tips, the seta? there 

 being somewhat acute and only slightly lilunt at the end. The suranal plate is triangular, smooth 

 on the surface, and with four glandular setw on each side. 



The caudal horn on first hatching of the larva is two-thirds as long as the body, or 2.. 5 mm. 

 in length. It is cylindrical and slowly tapers to the end, which is forked, each lobe bearing a 

 short, blunt seta, about half to a third as long as the horn is thick; it is blunt and a little swollen 

 at the end (PI. XLII. rig. 1). The horn is densely covered with microscopic glandular seta» 

 which arise from a tubercle, and are broad and forked at the end; occasionally there is one twice 

 as large as the others. 



It is worthy of notice that the fourth pair of mid-abdominal legs are remarkably thick, 

 being nearly twice as thick and long as the first pair. Also those of the first pair are smaller 

 than those of the second, and the second than the third. The larger size of the fourth pair is 

 evidently due to their exercise in grasping while the larva rests in the sphinx-like attitude, the 

 body being supported on this and the anal legs. The thoracic legs iire very pale vitreous green. 



Coloration: At about the middle of this stage the oblique pale whitish lines appear; all the 

 granulations are whitish green, paler than the pale green ground color. The seven lines nearly 

 meet on the back, nearly blending with the whitish median line. The four thoracic bosses are 

 whitish. The caudal horn is slightly fiesh colored. There are two parallel whitish dorsal lines 

 which extend along the body and include the four bosses, which are also whitish, not yellowish 

 green. There are five transverse wrinkles ("subsegments") on second and third thoracic segments, 

 the bosses being on the second wrinkle. 



The larva? molted August 12 to 16, 19U0. The young larviv either in this or the next stage 

 spins a thread, by which it hangs and assumes the sphinx attitude. 



Stage II. — Length, 12-15 mm.; width of head, 1| mm.; length of caudal horn, 2.5 mm. 

 The body is long and slender, the head at first somewhat wider than the body. The larm has 

 tiovi assumed the fundajneitfal characters of the final stage, the four thoracic false horns being 

 developed, and the integument of the head and trunk ])eing densely covered with sharp granula- 

 tions or secondary spinules. The head is pale green, with dense white conical secondary 

 tubercles or spinules of uneven size, two of which on the vertex are slightly larger than the 

 others. The trunk is yellowish green. Prothoracic segment with about twelve uneven conical 

 Vol. 9—0.5 3 



