OF ARTS AND SCIENCES. 77 



Stage V. — Moulted July 15-18. Length 40 mm. It differs from 

 the preceding stage in the rarely beautiful pale turquoise-blue edging 

 on the edge of the sur anal p^ ate and anal legs, and in the pale bluish 

 tint on the ends of all the tubercles, and at the base of the middle 

 abdominal legs. 



The head is lemon-yellow as before, about one half as thick as the 

 body, and is bluish on the region of the eyes. The prothoracic seg- 

 ment is lemon-yellow, edged with pale blue, while the tubercles are of 

 a beautiful pale turquoise tint. The tubercles are still long and 

 slender, those of the thoracic and last two segments scarcely larger 

 than the others. 



In this genus the tubercles are remarkably long, with short, small, 

 pale radiating bristles, much shorter and slighter than in Platysamia. 



The suranal plate also in Stage V. bears two low bosses ivithout 

 bristles (only their rudiments), while in P. cecropia these tubercles 

 with their bristles are well developed ; it also differs in the black spots 

 of the last stage. 



Those of the dorsal and subdorsal rows are pale whitish green at 

 base, passing towards the end into pale turquoise-blue. The infra- 

 spiracular row of tubercles are ringed with black at the base. The 

 black spots on the body are as in the previous stages. The thoracic 

 and abdominal legs are lemon-yellow, the latter pale bluish at base 

 and on the planta. The suranal plate and dorsal region of the 9th 

 segment are lemon-yellow, the thickened much swollen edge of the 

 suranal plate is turquoise-blue, including the tubercles, and the edge of 

 the anal legs is of the same tint, the blue suddenly expanding on the 

 lower side above the crotchets. 



In this stage the body in general is turquoise bluish white, rather 

 than pure white or slightly yellowish white, as in Stage III. 



August 20th one spun a cocoon, and the others stopped growing, 

 perhaps partly on account of the cooler climate than their parents had 

 experienced, though the season of 1890 was a warm one for Maine. 



By the larval characters this Chinese or Eastern Asiatic genus is 

 much more closely allied to Platysamia than to Attacus, though the 

 imago perhaps has more of the habit and general form and appearance 

 of Attacus. It differs from Platysamia in the rather slenderer body, 

 the decidedly longer tubercles, and the slighter, shorter bristles arising 

 from them, and in coloration by the pale lemon-yellow skin, with the 

 conspicuous black spots, and the beautiful turquoise-blue markings, 

 as well as the peculiar soft white bloom on the skin. How far this 

 style of ornamentation adapts it to its native Asiatic food plant we 

 do not know. 



