162 MEMOIKS OF TUE XATIOXAL ACADEMY OF SCIENCES. 



diverging tubes, out of wliidi the spraj' is probably forced. Tlieir ends do not reach to the sides 

 and are not visible from them, but the gland is nuicli as tliat of Ceiiua as figured by I'onltou 

 (Trans. Ent. Soc. London, 1887, PI. X, fig, 7.) 



littKje III. — August (i. Length, 11 mm. The head is now pale amber, but still dusky on the 

 vertex, and it is also still wider tlian the body. On each side of the body is a faint whitish 

 subdorsal line. The "caudal horn" is dark brown, now nearly as long as the eighth segment is 

 thick vertically. The horn is slightly retractile in tliis stage, and the base is movable, being 

 capable of withdrawal and extension and is distinctly nutant, the apex sometimes hanging over 

 backward. The sides of the body along the base of both the thoracic and abdoniina! legs are 

 now dark reddish chocolate brown, being of the same color as the horn. 



Till- liitcrul ydluw line is ircll iiiarl,-ciL The body beneath is pale green. The spiracles form 

 a dark dot surrounded by pale greenish. 



Stage IV. — Length, 20 mm. August L'o. The body is now thicker than before. The head 

 is distinctly bilobed, lounded, narrowing a little toward the vertex. The caudal horn is now 

 large!', higher, and more acute than in the preceding stage; it is freely elevated or allowed to fall 

 over backward, is soft and flexible, but very slightly retractile, and bears a few scattered fine 

 bristles. It has a blackish shade extending up from a point above the last spiracle to the apex, 

 which is dark. The bodj' is chocolate colored; the head redder, finely mottled with i)alcr 

 reddish. The suranal plate is well rounded behind, the surface roughened, witli no piliferous 

 warts, and this and the anal legs are nuire reddish than the body, being of a reddish pink hue. 

 The spiracles are much larger than in Stage 111, and are blackish, surrounded by a broad, jjale, 

 Hesh-colored ring. The middle abdominal legs have a shining chitinous black patch above the 

 l)lanta. there being no such jjatch on the anal legs. The thoracic legs are dark, pitchy and)er. 



Mature larva. — Length, -Id mm. The head is usually of the reddish color of the body, but 

 ligiiter and mottled. Now all the characters of the larva are assumed. The body is of a iicculiar 

 pearly hue, with a porcelain like polish, the head being of the same tint as the body. The head 

 is smooth, not quite so wide as the ])rothoracic segment, which is much smaller than the 

 somewhat swollen second thoracic segment. All the segments are sliglitly swollen in the nuddle. 

 The eighth abdonnnal segment is swollen dorsally, and is surmuuuted by a high, rather stiff, well- 

 deveh>ped horn, which is not granulated, but somewhat annulated; it is black, this tint extending 

 as a blaek lateral line below and l)ehind the si>iracle. The suranal plate is of |)eculiar shape, 

 being long crescentie, and l)earing a small knob in front, the surface of the whole plate being 

 coarsely granulated, rust-red, beconnng greenish in front. The thoracic feet are deep amber-red 

 or saluKin color. Of the alxlominal feet the first four i)airs are large and thick, conical, blackish 

 in tlie middle, while the anal pair are very small, with a rustred callous spot exteinally. On the 

 underside of the abdominal segments is an irregular greenish median line. Spiracles conspicuous, 

 black, ringed with yellowish white or nearly white. One observed August .'50, immediately after 

 nn)lting, had a very large head, nearly twice as wide as the slender body, and the suranal jtlate 

 was enormous, very wide in i)roport,ion to the width of the body. Horn freely movable, wrinkled 

 around the base, veiy black, and tlie black line on each side descends nearly to the spiracle, and 

 is very distinct on the purplish reddish skin. 



Rfcapifuldtion. — I. (Congenital characters.) The median dorsal tubercle or incipient "horn" 

 on the eighth abdominal segment is in Stage I plainly seen to be double, the result of the 

 coalescence and specialization of wdnit wei-e originally two dorsal warts. In Stage II this 

 tubercle becomes a well developed, high, conical, liesliy horn. 



li. (xVcipiired or adaptational characters). The prothoracic plate of Stage I disappears in 

 Stage II. 



.'}. Ajiijcaranee in Stage II of the dark reddish brown spots and band on the sides of the body. 



4. A])pearance in Stage III of traces of a whitish subdorsal line, while the lateral yellow line 

 is well marked. 



5. Horn in Stage IV becoming mui'li as in the last stage, though more flexible. 



Cocoon. — "While ."Mr. (ioodiiue states that "the transformation takes i)lace in a slight cocoon of 

 dead leaves fastened together with a few silken threads, on the surface of the ground, nuich in the 

 nmnner of Darapsa myron,"' Mw Tepper remarks that the caterpillar enters the ground to jjupate. 



