[450 



30 



Ap2}le variety. 



Body black, with four narrow, 

 pale-yellow stripes upon the 

 sides, nariower than the inter- 

 vening spaces. 



Upper side of the neck, or 

 first segment, deep, wax-yel- 

 low. 



Hairs upon the body whitish 

 — about as long as the width 

 of the body. 



Sumach variety. 



Body black ; in some speci- 

 mens, very dark-red, with 

 bright lemon-yellow stripes as 

 wide as the intervening spaces. 



Top of neck black, sometimes 

 with a narrow anterior margin 

 of yellow. 



Hairs same. 



Black Walmit variety. 



Body whollj- black, without 

 stripes. 



Top of neck black. 



Hairs pirre white — twice as 

 long as the width of the body. 



The dissimilarity of the black walmit variety from the otliers, is very 

 remarkable; so much so, that judging- from the mature larv* alone we 

 should never suspect them to be the same, or even a closelj^ allied spe- 

 cies. But previously to the last moult, this variety is striped like the 

 others, and it has jirecisely the same manners in feeding and moulting ; 

 and I have seen individuals, after the last moult, with short hairs as in 

 the other varieties. 



With respect to the coloration of the corresponding moths of these 

 three varieties, a certain relation can be observed to that of their re- 

 spective larvie. The. moths proceeding from the apple-feeding variety, 

 are of a russet or reddish-brown color, varying considerably in shade in 

 different individuals. These may be taken as the types of the Datana 

 ministra proper. The moths from the sumach larvte, with their broader 

 and brighter yellow stripes, are of a pretty uniform buff-yellow color, with 

 a conspicuous dusky spot a little below the upper extremity of the second 

 transvense liue, and a smaller dot opposite to it, between the tirst and 

 second lines. This variety partially combines the characters of D. per- 

 spicAia and D. major of Grote and Eobinson, having the bright, buff- 

 yellow color of the former, but without its continent first and second 

 cross lines, and the discal spots and other characters of the latter. 



Tlie moths from the unmixed black caterpillars found ui)on the black 

 walnut, are much darker tliau the others, being of a smoky-brown color of 

 different shades, but sometimes approximating- to the russet brown of 

 the a])ple ai.d the oak varieties. The space between the first and sec- 

 ond cross lines is usually darker in this variety, than the rest of the 

 wing. 



Besides their diversities of color tlie varieties of Datana ministra differ 

 also, but only in a slight degree, in the number and direction of the 

 cross lines, the proportional width of the wings, and the depth of tlie 

 crenulations or little rounded notches in the teiminal margin of the up- 

 per wings. But Mr. Walsh has shown by the comparison of many spe- 

 cimens, (Proceedings of the Ent. Soc. of Philadelphia for 1865, page 

 IM) that these variations ])ass into each other by insensible gradations, 

 and therefore that they cannot be relied upon as specific characters. 



