1868.] 349 



Boston, Jan. 2Gth, 18G3, severally acknoNvleilging their election to Corres- 

 ponding Membership in the Society. 



A communication was read from Bonj. !.). Walsh, Esq., dated Rock 

 Island, TIL, Jan. 19th, 1863, submitting the following observations on 

 Papilio glaucus and Papilio turnus: — 



" That Turnus and Glaucus are identical, seems to be proved by two facts, 

 the one positive, the other negative. First ^ I am informed by Mr. Ed- 

 wards that Mr. Newman and Mr. Wood of Philadelphia both say they 

 have raised the black 9 , together with several shades of color between 

 yellow and black, from the same laying of eggs. Si'roiuJ, nobody ever 

 saw a % Glaucus. — Mr. Edwards indeed once informed me that he 

 knew of such a specimen, but it proved subsequently, on a closer examin- 

 ation by him, to be a 9 . Now .Glaucus is so common in southern lati- 

 tudes, that if it were a true species, not a mere sexual distinction, some- 

 body or other ynust have met with the % , particularly as in Papilio the 

 males are generally three or four times as numerous as the females. 



There is another phenomenon connected with this species of Papilio, 

 which has never, I believe, been hitherto elucidated. In New York and 

 the New England States, as I learn from Mr. Edwards, the 9 of Turnus is 

 always yellow. " He never" he says "saw a black 9 himself, or knew of 

 one being taken by any of his correspondents in that region, though he 

 has often taken the yellow 9 . But from Philadelphia south there are 

 many black ones." In the summer of 1861, when I was myself entomol- 

 ogiziug in the extreme southern point of Illinois, I captured in one clover 

 field between 70 and 80 specimens of Turnus, with the express object of 

 investigating this question of the sexes. Every single yellow one was a 

 % , and every single black one a 9 , the former being to the latter about 

 as 4 or 5 to 1. There was indeed a single black one which from the 

 shape of the abdomen I thought at first might be a S , but on squeezing 

 out the contents of the abdomen, eggs made their appearance, and eifectu- 

 ally demolished the supposition. On the other hand, in Ptock Island, 

 which lies in about 41° 30', both black and yellow 9 9 occur, but the black 

 form is 5 or 6 times as numerous as the yellow, judging from the careful 

 observation of five years. The point in southern Illinois just referred to 

 was in the same latitude as Richmond, Virginia. 



On these data, which however require to be confirmed by additional obser- 

 vations, I incline to the opinion that south of about 38° in the Valley of 



