536 , [December 



under the circumstances I prefer to retain the one proposed by Mr. A. 



S. Packard, Jr. 



Halisidota tessellaris, Abbot and Smith. 



From Mr. Benj. D. Walsh's description of Halesidota Anttphola. 

 Proc. Boston Soc. Nat. Hist. February, 1864, p. 288, I am enabled to 

 refer it as a synonym to the present species. That the imago is en- 

 tirely identical with Abbot and Smith's species is conceded by Mr. 

 Walsh in the first lines of his description : " The imago of this species 

 is utterly undistinguishable from that of H. tessellaris^ Sm. Abb. and 

 Harr." The validity of the supposed species rests upon a stated differ- 

 ence of larval structure affecting the location of the "' hair pencils," a 

 differing coloration of the latter and a varying food-plant. Subsequent 

 investigation, I am informed, has contradicted the first of these asserted 

 differences, which, indeed, on the supposition that it existed, would ra- 

 ther indicate a generic than a specific character, and I consequently 

 omit any further remarks upon it. There remains, then, a differing 

 coloration of the larval " hair pencils" and a differing food-plant as the 

 totality of specific characters which are to constitute the new species. 

 Analogous instances of larval variation in the coloring of the "hair" 

 among members of the present family have been discovered without 

 having been made the basis for the description of a new species, and 

 may be correctly regarded as simple variations within the " well defined 

 limits of the species," while the habits of the differing larva as to the 

 food-plant, especially in such an essentially polyphagous family as the 

 Arctiidae, can with difficulty be drawn in as a specific character, even 

 upon much more detailed and perfect evidence than Mr. Walsh has 

 offered in the present instance. Should my views on this description 

 of Mr. Walsh's obtain, and more especially on a second to be hereinaf- 

 ter mentioned, it will ensue that the "Entomological Speculations" 

 based upon the view of the validity of these of Mr. Walsh's species, 

 and given in so-called "gradations" on page 298, 1. c. will of them- 

 selves fall to the ground. It is not the most inconsistent part of Mr. 

 Walsh's Paper, that while H AnfijjJiola is published as ■' n. sp.," it is 

 regarded on page 298 as merely in process of "formation;" no sucb 

 forms have been hitherto announced in Entomological Science, and a 

 specific name in its present acceptation is only improperly to be applied 

 to them. 



