340 [May, 



knowledging the receipt of the Proceedings of the Academy, Vol. 6, 

 Nos. 1 6, and Journal, Part 3, Vol. 2, new series. 



From M. Prosper Farbe, dated Philadelphia, 22d May, 1855, ac- 

 companying the donations acknowledged this evening. 



Mr. Isaac Lea read a paper, intended for publication in the Proceed- 

 ings, entitled " Description of a new Mollusk from the Red Sandstone 

 near Pottsville, Penn. j" which was referred to Dr. Leidy, Dr. Wilson 

 and Mr. Vaux. 



Dr. Leidy stated that he had received from Dr. Nott the bones of the 

 so-called fossil man, exhibited in New Orleans several years since. The 

 skeleton was 18 feet in length. There were two molar teeth, each 

 weighing two pounds, and the fragment of a canine. The bones are 

 those of the Mastodon. Dr. Leidy described the mode in which the 

 skeleton was made up. 



Dr. Leidy also announced to the Society that the fine skeleton of the 

 Narwhal, (Monodon monoceros) which had been presented by Dr. Kane 

 in 1851, had been mounted, and was now in the Museum. 



May 29th. 



Vice President Bridges in the Chair. 



The Committee to which was referred the following paper, by Mr. 

 Isaac Lea, reported in favor of publication in the Proceedings : 



Description of a new Mollusk from the Red Sandstone near Pottsville, Pa. 



By Isaac Lea. 



A few weeks since Dr. Leidy had the kindness to place in my hands an in- 

 teresting specimen, consisting of a cast of a bimusculose mollusk which that 

 gentleman had found last summer at Tumbling Run dam, about a mile south- 

 east of Pottsville. 



The discovery of this small specimen in these Red Sandstones (Formation No. 

 11 of the Pennsylvania Survey, by Prof. Rogers) is of great importance, as it is 

 believed to be the first mollusk which has been observed in these Red Sandstones, 

 underlaying the conglomerate of the coal measures of Schuylkill County, known 

 as the southern coal field of Pennsylvania, and consequently congenerie with 

 the Sauropus primcevus , Lea, and Plumites, Rogers.* 



The extreme paucity of organic life yet observed in these Red Sandstones ex- 

 cites the more interest, as the fact of such deficiency of types renders the position 

 of this formation in the series a matter of doubt in the minds of some geologists. 



It is hoped that by patient' research other mollusks may be discovered, and 

 that, by the palaeontology of this portion of the Palaeozoic rocks, its true position 

 may be determined. 



The specimen is simply a cast of the exterior of the two valves, entirely 

 flattened out. In its facies it approaches the Cypricardia rhombea, Phill., (Geology 

 of Yorkshire, pi. 5, f. 10,) from the Mountain Limestone of Northumberland, 

 England. It is, however, rather more quadrate, and is a much smaller shell. It 

 has strong affinities to Posidonia, particularly in the strice, and may possibly 



* Mr. Hall, in the New York Reports, part 4, p. 292, describes a Cypricardia 

 (contracta) from the " Conglomerate and Sandstone" under the great western 

 coal measures, near Panama, Chatauque County. It is quite oblong, and of much 

 greater breadth and of a larger size than the species described herein. 



