MEMOIRS OF THE NATIONAL ACADEMY OF SCIENCES. 225 



From the inspection of the tiguro by DoubleiUiy (jjiobably copied from Abbot's colored 

 -drawing) of the larva of Lochmwus mnnteo Doubleday, I feel sure that Heterocampa siibalbicans 

 (Irote is a synonym. Indeed, it has been referred witli a doubt by Mr. Grote to his species. 

 I iun indebted to Professor Eih'y for an opportunity of examining and (U'scribing a series in 

 ah'oliol of the larvffi in all the five stages (No. 2759 from box 12, 1.55), and have myself collected 

 the caterpillar in its hist two stages, while Professor Riley has given me a blown S])ecimeu and 

 the opi)ortunity of examining his own series. 



Larva, Stage I. — Length, 4-G 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. Tiiere are six to 

 seven minute piliferous warts, the Idack set;e arising froai them being unusually large and stiff, and 

 tai)eriug at the end; around the base of the warts are brown discolorations, and the row of warts 

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

 brownish baud. 



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

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

 on the-prothoracic and first abdominal segments arc of about the same size, and or.ly 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 first 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-likc and black; near the middle 

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

 •excremontiferal bristle. The anal legs are long and slender, being as long as the ninth segment, 

 and are slightly retractile. The four anterior pairs of abdonunal legs bear on the plant;? from 

 sixteen to eighteen crochets. The setiB 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 

 and second and seventh and eighth abdominal segments is a series of singular battledoor-like 

 ■setiTp, 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 seta^, are very short, only from one-third 

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

 bulbous expausion, the surface of which is striated or wrinkled longitmlinally, while the tip 

 appears under a half inch objective to be clear. There is also a i)air of i-emarkable foliaceous 

 oval appendages at the end of the 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 i)reserved in the alcoholic specimens examined, may be described in 

 the abseuce 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 setre 

 are brownish, aud there are pinkish stains at the base of the prothoracic and first aud 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. — Length, 10-11 mm. The head is now proportionately smaller tlian before, the 

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

 abdominal segments, while uot much larger than tlie others, are much darker reddish brown, with 

 pink 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 tuliercles, 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 yeUow line is distinct. The stigmata ou the eighth abdominal segment is twice as 

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

 seta- in this stage. The anal legs are provided with crochets. 



' Proceediui's Bost. Soc. Nat. Hist., 1800. 

 S. Mis. .50 15 



