194 TRANS. ST. LOUIS ACAD. SCIENCE. 



larvae could be separated with any certainty, while the chrysali- 

 des are wrongly represented hanging by the tip of the body, at 

 right angles from the point of attachment (which they never do), 

 rounded and entire dorsally (they are notched and angular), and 

 without a single generic character that belongs to them. Nor au- 

 thors nor draughtsmen, if they ever saw the earlier stages of these 

 butterflies, could have looked at them with any degree of care ; 

 and it is quite natural that neither the descriptions in Morris's 

 " Synopsis," which are abridged from the /conograp/iie, nor the 

 figures in Glover's unpublished Plates, which are copied from 

 the same, should gain in lucidity. Dr. Asa Fitch* makes a brief, 

 allusion to J/erse, but the information he communicates is evi- 

 dently obtained from the Iconographie just mentioned, as it contains 

 the same errors. None of our other standard entomological 

 authors refer to these butterflies, for which reason a few facts re- 

 garding them may not be uninteresting. 



They both feed on Hackberry (Gf/Ziy), and, so far, I have found 

 them on no other plant. The Hackberry is suflficiently common 

 in the bottom lands of Missouri, and two tolerably constant forms 

 are easily recognizable : i — {occidentalis Linn.) with broad, rough- 

 ish, sharply serrate leaves, purple-black drupes, and rather pale 

 bark, which on the trunk is rough and strongly cleft so as to look 

 as if hacked ; 2 — {Mississippiensis Bosc.) with smaller, narrower, 

 darker leaves, less serrate and often entire, yellow drupes, and 

 darker bark, the trunk appearing knotty. A third form {crassifolia 

 Lam'k), having most the aspect of Ulmus^ occurs less frequently. 

 It is much \^e occidentalism but with more supple limbs, and rough- 

 er, thicker leaves, which, when plucked, wilt much more rapidly 

 than do those of the other forms. Botanists differ as to whether 

 these forms are specific or varietal. Dr. Gray refers them all to 

 occidentalism and, as intermediate varieties are found and the seed- 

 lings from the same tree are exceedingly variable, this seems the 

 proper course. But Prof. Planchon, who has monographed the 

 genus, considers i and 2 good species, and the third doubtful. 

 The two butterfly larvae I am about to speak of feed indiscrimi- 

 nately on all three, but, so far as my experience goes, show a 

 preference for occidentalis. 



♦jrdN.Y. Rep , § 83. 



