1885.] natural sciences of philadelphia. 49 



March 17. 



Mr. George W. Tryon, Jr., in the chair. 



Twenty-four persons present. 



The following papers were presented for publication : — 



" Entomologia Hongkongensis. — Report on the Lepidoptera of 

 Hongkong," by F. Warrington Eastlake. 



" Description of a supposed new species of the genus Cyano- 

 corax," by Alan F. Gentry. 



The death of Titian R. Peale, a member, was announced. 



March 24. 

 The President, Dr. Leidy, in the chair. 

 Twenty-six persons present. 



Remarks on Mylodon. — Prof. Leidy remarked that among the 

 fossils of Mastodon, Equus, etc., from the salt mines of New 

 Iberia, La., noticed in the Proceedings of 1884, p. 22, there are 

 three teeth, which are probably to be referred to the reputed 

 Mylodon Harlani. Of this species we are sufficiently well 

 acquainted with the posterior three lower molars, but know little 

 of the first lower molar, and nothing of the upper teeth. One 

 of the Louisiana specimens accords in form and size with the 

 third lower molar, in the best preserved jaw-fragment (see 

 Extinct Sloth Tribe, pi. xiv, 1, 2), from Big-bone-lick, Ken., 

 regarded as characteristic of Mylodon Harlani. The other 

 Louisiana specimens, in comparison with the complete dental 

 series in both jaws of Mylodon robustus, as represented in the 

 famous memoir of Prof. Owen, are so unlike any of the teeth of 

 this animal, that they might readily be considered as pertaining 

 to another genus. One of the specimens, of which the tritu- 

 rating extremity and a transverse section are represented in the 

 outline figures 1; 2, he took to be a first lower molar. It has lost 

 all its cementum, but is otherwise well preserved. It is worn off 

 in deep slopes, of which the posterior is more than an inch 

 long, and the anterior little less than an inch. The transverse 

 section is reniform, widest in front, and agrees in shape and size 

 with a fragment of the corresponding tooth (pp. cit., pi. xvi, 19 a) 

 retained in the jaw-fragment from Kentucky. In all the teeth of 

 Mylodon robustus, the triturating surface inclines comparatively 

 little from a level. Such also is the case in all the teeth of the 

 ramus of a lower jaw, from Natchez, Miss., attributed to a half- 



