NATURAL SCIENCES OP PHILADELPHIA. 257 



April 1. 



The President, Dr. Ruschenberger, in the chair. 



Twent3'-nine members present. 



The following paper was presented for publication : 

 " On the Affinities of the Sirenians." By Theo. Gill. 



Dr. Leidy presented an interesting specimen of bituminous 

 coal from the mines of the Westmoreland Coal Company, West- 

 moreland Count}', Pennsylvania. This specimen is a gift to tlie 

 museum, from George C. Hewett, Esq., Mining Engineer, who 

 furnislies the following details : The seam from which the speci- 

 men is taken is noted for its regularity and freedom from faults. 

 Occasional cracks, however, occur sometimes several hundred feet 

 in length. In these cracks incrustations of iron pyrites are found 

 in various forms, of which an unusual one is shown in the present 

 specimen, viz., in the form of stalactical prolongations. The 

 remaining portions of the vein consist of remarkabl}'^ pure coal 

 especially suited for the manufacture of illuminating gas. 



Prof. Leidy remarked that the rat presented this evening by 

 Mr. L. Fussel was a specimen of the l>lack Rat, or Mus rattus, 

 which had been caught on board a ship in the vicinity of the city. 

 This rat is exceedingly rare, but is said to have once been com- 

 mon enough, and is also said to have been nearly exterminated 

 by the common brown or Norway Rat. 



Prof. Leidy also exhibited a specimen of iron ore, recently 

 sent to him by Dr. George W. Lawrence, of Hot Springs, Ark. It 

 was the mineral Dufreynite, and was found in Polli Co., Ark. 



April 8. 

 The President, Dr. Ruschenberger, in the chair. 

 Twenty-eight members present. 



Dr. LeConte announced the death, at Davidsburg, York Co., 

 Pa., on the 10th March, of Friedrich Ernest Melsheimer, M.D., a 

 correspondent of tlie Academy, aged nearl}' ninety-one years. . He 

 inherited great taste for entomology from his father, E. F. Mels- 

 heimer, a clergyman, who cultivated natural science with much 

 success, and not only was a highlj^ esteemed correspondent of 

 Knocii and other European entomologists of the end of the past 

 and beginning of the present century, but an active collaborator 



