156 proceedings of the academy of [1880. 



April 6. 



The Tresideiit, Dr. Ruschenberger, in the chair. 



Forty -two persons present. 



The death of Wm. Theodore Eoepper, a correspondent, was 

 announced. 



April 13. 

 The President, Dr. Ruschenberger, in the chair. 

 Twenty-eight persons present. 



A paper entitled " Description of a New Species of Catosto- 

 mus (C. cypho), from the Colorado River," by Wm. X. Locking- 

 ton, was presented for publication. 



The death of M. Laporte, Count de Castelnau, a correspondent, 

 was aimounced. 



Remarks on Pond Life. — Prof. Leidy remarked, that at the 

 invitation of Mr. Joseph W. Griscom, he had recently visited 

 some little ponds in the vicinity of AVoodbury, New Jersey, 

 which were remarkable for the profusion of minute invertebrate 

 life. The ponds oceup}' hollows in the woods, and consist mostly 

 of accumulated rain water, though several are likewise supplied 

 by springs. Several are completely di'ied up during the summer. 

 Mr. Griscom says they continue rich in animal life even during 

 the winter. 



Of animals, entomostracans are. exceedingly numerous and 

 varied. Amono- some of the most beautiful and conspicuous were 

 noticed abundance of Brancliipus, of which two species from, 

 the same locality have been recently described by Mr. Ryder, 

 under the names of Chirocephalus holmanii and Streptucejihalus 

 sealii. There are also wonderful multitudes of many species of 

 copepods, ostracods and cladoceres, several of which are con- 

 spicuous for their large size and bright red color. 



In one of the ponds a bright green Hydra was frequent, and in 

 another a pinkish one was abundant. These appear to be the 

 H. gracilis and H. carnea of Agassiz, but it is a question whether 

 they are not the same as the H. viridis and H. fusca of Europe. 

 Some of the Hydras were of a bright red color, and Mr. Griscom 

 intimated that this was due to the pinkish variety feeding on red 

 entomostracans. This was confirmed by some of the pink ones 

 which were brought home and kept in a jar with abundance of 



