140 



[July, 



Mr. Ord transmitted a letter from Matthew Bsrr, dated Paisley, 21st 

 June, 1856, acknowledging the receipt of ^64 lis. 7d. as a contribu- 

 tion to the Wilson testimonial fund. 



Dr. Leidy stated, that in consequence of the unsatisfactory results of bis in- 

 vestigations, wliich had formed the subject of "A Memoir on the Extinct Dico- 

 tylinas of America,"* from the time of writing that memoir he had been col- 

 lecting material, both recent and fossil, towards a more positive determination 

 of the number of extinct species of Dicotylinae. The results of his subsequent 

 investigations appear to be as follows : 



1. The extent of variation in the characters of the skull, and especially of the 

 teeth, is as great in different individuals of the recent Dicoiyles torquaivs, as it 

 is in all the extinct genera and species heretofore indicated by Dr. Le Conte and 

 himself. 



2. The evidence, so far as it has been derived from osteological characters, 

 appears to refer all the extinct genera and species of North American Dicoty- 

 linse, as heretofore indicated, to one single species. 



The name of the latter and its synonyma are as follows : 



DicoTTLES coMPRESsus, Leidy. 



Syn. Platigonus compressus ; Hyops depressifrons ; Proiochoervs prismaiiciis ; Di- 

 eotyUs depressifrons ; Dicoiyles costatus, Le Conte. Euchoerus macrops, Leidy. 



July \btJi. 



Dr. Bridges, Vice President, in the Chair. 



A paper was presented for publication in the Proceedings, entitled 

 '< New species of Plyla, by John Le Conte," which was referred to a 

 Committee consisting of Dr. Hallowell, Mr. Cassin and Dr. J. A. Meigs. 



July ^9lh. 



Vice President Bridges in the Chair. 



The Committee on Dr. Girard's paper, read 8th inst,, reported in 

 favor of publication in the Proceedings ; which report was adopted. 



On a New Genus and Species of Urodela, from the collections of the U. S. Expl. 

 Exped., under Comm. Charles Wilkes^ U. S. N. 



By Charles Gieard, M. D. 



A species of this group was collected in Oregon by the U. S. Exploring Ex- 

 pedition, showing such a striking external resemblance with Aneides lugubris, that 

 upon a first examination we referred it to the latter genus. A closerexamination of 

 its structure made us acquainted with an ensemble of characters which has 

 induced us to establish a genus distinct from Aneides : by the shape of the mouth, 

 which is linear, instead of being undulating; by the maxillary teeth, which are 

 exceedingly minute, and the disposition of the vomero-palatine teeth, upon a 

 double ogee, instead of an obtuse angled triangle. 



HEREDIA. 

 Head subelliptical, broader than the body ; snout blunt and rounded, protru- 

 ding beyond the lower jaw. Cleft of the mouth oblique and rectilinear. Maxil- 

 lary teeth exceedingly minute, scarcely perceptible. Vomero-palatine teeth dis- 



Trans. Am. Phil. Soc. x., 323. 



