1855.] 395 



The Committee on a paper by Dr. J. Aitken Meigs, entitled " Re- 

 lation of Atomic Heat to Crystalline Form." reported in favor of publi- 

 cation in the Journal. 



On leave granted, Dr. Leidy presented for publication in the Pro- 

 ceedings a paper entitled " Indications of twelve species of Fossil 

 Fishes," which was referred to the following Committee : Mr. Cassin, 

 Dr. Le Conte and Dr. Hallowell. 



On leave granted, Dr. Carson presented a paper, intended for publi- 

 cation in the Journal, entitled " Descriptions of a new species of Carica, 

 by Jose del Solar, of Lima, Peru." Referred to Dr. Carson, Dr. Bridges 

 and Major Le Conte. 



ELECTION. 



The Rev. Henry S. Spackman, Mr. Stacy B. Barcroft, Dr. Richard 

 Clements, and Dr. Henry Tiedemann, of Philadelphia, were elected 

 Members. 



August 28th. 



Vice President Bridges in the Chair. 



The Committee to whom was referred Dr. Leidy's paper, entitled 

 " Indications of twelve species of Fossil Fishes," reported in favor of 

 publication in the Proceedings. 



Indications of Twelve Species of Fossil Fishes. 

 By Joseph Leidy, M. D. 



1. Myliobates serratus. Based upon a specimen consisting of four median 

 dental plates, with parts of two others and the first row on each side of lateral 

 dental plates. The triturating surface of the specimen is quite level, except that 

 it is slightly depressed along the median line, and slopes off in a concave manner. 

 The median dental plates are united by sutures slightly convex forward, and 

 distinctly serrated at their outer part. The first row of lateral dental plates are 

 nearly hexagons, and they are connected with each other and with the median 

 plates by distinctly serrated suture. 



The attaching surface of the specimens forms two planes inclining to a median, 

 convex angle. 



Breadth of median plates 10 J lines, width antero-posteriorly If lines. 



Locality. Discovered by Dr. C. H. Budd, in the Green Sand of Burlington Co., 

 New Jersey. 



Remarks. The specimen closely resembles a corresponding one characterized 

 by Agassiz, as Myliobates suturalis. 



2. Myliobates rugosus. Based upon a specimen, consisting of four median 

 dental plates, indicating a large species of the genus, though not so large as the 

 Myliobates Holmesii, Gibbes, which, however, appears rather to be an Aetobatis, 

 judging from Dr. Gibbes' figures,* of the same type as the A. eximius. The two 

 latter might be considered as the representatives of a new genus, in which there 

 exists a median row of dental plates, and a single row laterally of small tri- 

 lateral plates. It would be intermediate to Aetob-itis and the true Myliobates, and 

 might be called Mesobatis. The triturating surface of the specimen of Myliobates 



* Journ. Acad. Nat. Sc. 2d s. i. pi. 42, fig. 1. 



