NATURAL SCIENCKS OF PHILADELPHIA. 137 



dilia. Similar differences exist between the Illinois Batrachian and Dendrer- 

 peton (Owen) ; the latter possesses also a double row of teeth. Hylonomus, 

 (Dawson), supposed to possess Lacertilian affinities, exhibits ribs and bicon- 

 cave vertebra. The ribs of Telerpeton will distinguish it also. The only 

 genus as yet known to approach closely that under consideration, has been 

 described by Prof. J. Wyman under the name of Raniceps.* This animal is 

 only known from a study of the inferior aspect of a portion of the skeleton ; 

 nevertheless it is certainly different, being nearly double the size, and having 

 relatively longer and stronger anterior limbs. The angles of the mandible 

 appear to have been considerably more incurved than in the Illinois species. 

 They may have belonged to the same genus ; in that case the name here given 

 will not prove superfluous, as the older appellation was previously applied 

 to a genus of Gadid fishes. 



The name Amphibamus grandiceps has reference, first, to its two 

 modes of progression ; its flattened oar-like tail enabled it to swim in the 

 waters of the swamps. of the coal period, and its elongate, clawed digits indi- 

 cate ambulatory power ; perhaps it climbed upon the low limbs of the Sigil- 

 lariaa that rose above the water. The animal was most probably nocturnal 

 in its habits. The humors of the eye could not have escaped far beyond 

 their natural envelopes, so that the subsequently formed limestone has been 

 hardened, and so fractured in nearly the form of the ball. On the fractured 

 surface below and under the remaining palpebral scales, the mineral is dis- 

 tinctly blackened, as by the pigmentum nigrum ; below the margin of the lid 

 this is interrupted by a discoid spot of the form and dimensions of an iris, 

 which presents a median lenticular vacuity, again revealing the pigment, ob- 

 viously the vertical pupil of a nocturnal animal. The preservation of the out- 

 line of color is certainly remarkable in a specimen of such great antiquity. 

 A somewhat parallel case occurs in the preservation of the ink-bags of the 

 Sepia? ; these do not date further back th*n the Jurassic. These appearances 

 cannot be explained on any supposition of artificial production. 



August 1st. 



Mr. Cassin, Vice President, in the Chair. 



Twelve members present. 



The following paper was read and referred to a committee : 

 " Descriptions of new species of fossil Crinoidea, &c." By F. B. 

 Meek and A. H. Worthen. 



August Sth. 



Dr Ruschenberger, in the Chair. 



Ten members present. 



The following papers were read and referred to committees : 

 " Notes on a species of Whale found in the River Delaware," By 

 E. D. Cope. 



" On some Conirostral Birds from Costa Rica." By John Cassin. 



* Anier. Journ. Sci. and Arts, 1858, p. 158. 



1865.] 



