MEMOIRS OF THE NATIONAL ACADEMY OF SCIENCES. 



()9 



aiidthiM- I'l'ddish piirpli' line. Otlicrw isc tli(> iiuirkings are the same. The siinuiiil plate, liowever, 

 is edged with K'liion yellow, hoiiiir the contiiiuatiori of thi' hiteral yellow hand. 

 Thoracic and ahdoiniiial leys "oroeii tipi)cd with hi-owii" (Jewett). 



An cxaniiiiation of tit;-. !' (in the text) will illustrate better than a proli.x verbal description the 

 apjiearance of the spines in statues I and II of this s))(>cies. They are all drawn with the camera, 

 and it is to be observed that the "horns" are niort> like those of Cif/ieronia M/dlis than Earles 

 impenaliii. a, one of th(> horns on the second thoracic segment; a', the extremity enlarged, 

 showing the circular corrugations; n". the same more magnified; a'", a terminal spine enlarged, 

 showing its mode of insertion; it contains a central mass of minute globules; i, the first 

 abdominal segment enlarged to show the position of the dorsal, subdorsal, supraspiracular and 

 spiracular stripes, the latter inclosing the spiracle; also the position of the four spines, one dorsal 

 (i), one subdorsal (ii), and two infraspiracular; the spines are all minutely barl)ed; e, a dorsal 

 spine (/), bearing a spinule (ii) at its base; (/, ''caudal horn" or medio-dorsal spine on eighth 

 abdominal segment; ix. that on the ninth segment; it is small, conical, and forked at the end, 

 each fork bearing a long seta. All the foregoing in stage I. _/", a "horn" from the second 

 thoracic segment, stage II; the two terminal spines have etitirely changed in shape, being larger 

 and longer and bearing a tapering fine 

 liristle; a third smaller conical tubercle 

 has appeared near the base of one of the 

 forks. The spinules on the trunk now 

 bear a bristle; e, "caudal horn" of stage 

 II: now large and high, deeply forked at 

 the end; the spines or tubercles on the 

 trunk of the horn now bear each a slender 

 bristle. 



S'fafft' ///.—Molted July 20, 27. Length, 

 13-15 mm. (PI. XLVI, tig. 1). The head is 

 now inuch larger, high, the face subtrian- 

 gular, not black as before, with a green 

 lateral stripe, but pea-green with a yellow 

 stripe on each side, shaded more or less 

 with black between the j^ellow V; and on 

 the outside, in one example, the black is 

 reduced to a diffuse patch inside, while in 

 another larva it is outside of the yellow V. 

 The head is now nearly as wide as the 

 body. 



The eight horns are still about one-third 

 as long as the whole body and are now paler than before, being reddish chestnut and yellow at 

 base, with black spinules and blackish at the tips, which are now not bulbous, but irrogularlv 

 forked, the fork much shallower than in stage II; they are thicker than before, and the outer 

 ones of the first pair are much shorter than the dorsal ones. The spines along the body are 

 larger and stouter than before, with shorter setie; the tubercles at base are deeper yellow than 

 before, tipped with black, while the high, conical, or (sometimes) rounded granulations are snow, 

 white. The lateral yellow stripe along the body is more distinct than before; it is bordered 

 above with pure white, and above this is the linear dark purple spiracular line, shaded above 

 more distinctly than in the ijreceding stage with deep blue-green or verdigris-green; the caudal 

 horn considerably higher than before, being one-tifth as long as the whole body; it is pink, with 

 white spines bearing black bristles. The larva also differs from that of stage II in the suranal 

 plate, which is more deeply forked, the forks being thicker, larger, and with several tubercles; 

 the sides of the jjlate are heavily spined and G:>the surface are about six central, small, conical 

 spines. Now, the dorsal abdominal spines arc distinctly ivory-white on the outer side from the 

 base up to the dark tip. The spiracles are much larger than before, distinctly interrupting the 

 dark purple spiracular line, which is paler than before. 



Fig. 9. — A. bicolor. armature of stages I and II. 



