MEMOIRS OF THE NATIONAL ACADEMY OF SCIENCES. 225 



From the inspection of the figure by Donbleday (probably copied from Abbot's colored 

 •drawiii.i;) of the larva of Lochnueiis manteo Doubleday, I feel sure that Heterocampa sitbalbicans 

 Grotc is a syiiouyin. Indeed, it has been referred with a doubt by Mr. Grote to his species. 

 I am indebted to Professor Kiley for an opportiuiity of examining and describing a series in 

 alcohol of the larviB in all the five stages (Xo. 2759 from box 12, 155), and have myself collected 

 the caterpillar in its last two stages, while Professor Eiley has given me a blown specimen and 

 the opportunity of examining his own series. 



Larva^ Stage /.—Length, 4-0 mm. The head is very large, nearly twice as wide as the body, 

 and flattened in front, the outline seen from in front being somewhat six-sided. There are six to 

 seven minute piliferous warts, the black setne arising from them being unusually large and stiff, and 

 tapering at the end; around tlie base of the warts are brown discolorations, and the row of warts 

 on each side of the median line, together with the outer row, are connected by an irregular, faint, 

 browuisli baud. 



The body narrows in width to the end. The dorsal and lateral tubercles are well developed, 

 the dorsal ones being quite high, but on the whole rather small and all of the same shape; those 

 on the prothoracic and first abdominal segments arc of about tlie same size, and only a little larger 

 than those on the second and third segments; the two dorsal ones on the eighth abdominal 

 segment are of the same size as those on the lirst abdominal segment, but are nearer together and 

 with somewhat larger bases. The ninth and tenth segments are rather long, with well developed 

 tubercles. The supra-anal plate is well developed, being rounded, not so long as broad, bearing 

 on the edge eight hairs, of which the two posterior ones are bristle-like and black; near the middle 

 of the plate are two black dorsal bristles. The paranal lobes are large and full, each bearing an 

 ■excrementiferal bristle. The anal legs are long and slender, being as long as the ninth segment, 

 and are slightly retractile. The four anterior pairs of abdominal legs bear on the planta- from 

 sixteen to eighteen crochets. The setie arising from the dorsal and lateral tubercles are long and 

 ■large, and though apparently tubular, taper, some to a point, while others are slightly docked, 

 but they do not, as usual, end in a broad clear tip. But along the extreme lower side of the first 

 aiid second and seventh and eighth al>dominal segments is a series of singular battledoor-like 

 •setfe, a pair to each of the segments named, and arising from the lowest tubercle on the side of the 

 segment. 



These battledoor hairs, which are modified secretory setip, are very short, only from one-third 

 to one-half as long as the other seta-, and have a slender ])edicel enlarging into an elongate 

 bulbous expansion, the surface of which is striated or wrinkled longitudinally, while the tip 

 appears under a half inch objective to be clear. There is also a pair of remarkable foliaceous 

 oval appendages at the end of tlie thoracic legs, which we have not seen in the few other larva 

 whose feet we have specially examined. These are described and figured in our paper on the 

 " External structure of caterpillars." ' 



The colors, being well preserved in the alcoholic specimens examined, may be described in 

 the absence of the living. The head is amber, mixed with resinous. The body is whitish above; 

 the tubercles and their bases pale straw-yellow, as are the anal region and anal legs; the setaj 

 are brownish, and there are pinkish stains at the base of the prothoracic and first and eighth 

 abdominal dorsal tubercles. Hence it seems that in the first stage of this species the mode of 

 coloration of the final stage (V) is already indicated. 



Second stage.— Lengtlh 10-11 mm. The head is now proportionately smaller than before, the 

 dark spots more exaggerated, and the twin dorsal tubercles on the prothoracic and first and eighth 

 abdominal segments, while not much larger than the others, are mucli darker reddish brown, with 

 piidv stains around their bases, and thus contrast with the others, which are yellow. The two 

 double dorsal pink lines, connecting the prothoracic and first abdominal tubercles, also the four 

 short lines in front of and behind the tubercles on the eighth segment, are now distinct: also the 

 subdorsal, white, lateral band on the outer side of the dorsal tubercles, while the subspiracular, 

 narrow, pale yellow line is distin(;t. The stigmata on the eighth abdominal segment is twice as 

 large as the others. The hairs are veiy long, black, and tapering. I can not see any battledoor 

 ■setic in this stage. The anal legs are provided with crochets. 



I Proceedinga Bost. Soc. Nat. Hist., 1800. 

 S. Mis. .50 15 



