NATURAL SCIENCES OF rHILADELPIITA. 221 



December 8. 

 The President, Dr. Ruschenberger, in the chair. 

 Twenty-eight members present. 



Continuous Oroivth in Fungoidal Excrescences. Mr. Thomas 

 Meehan exhibited some excrescences, growing on branches of 

 Querciis tivctoria.^ the black oak, gathered from ab(3ve tlie remarka- 

 ble quarry of broken rocks at Edge Hill, which had been brought 

 to the notice of the Academy last year by Mr. Rand, and remarked 

 that all familiar with our forest features must have often seen 

 similar excrescences, which were the work of insects, and partook 

 of the nature of galls. An examination of these exhil)ited showed 

 them to be of fungoid origin, and similar in their nature to the 

 familiar knots on the plum and cherry, whicli through the re- 

 searches of the late Mr. Walsh and Prof Peck, of Albany, were 

 now known to be of fungoid, and nut of insect origin. These, 

 however, and he believed most of the excrescences of this character, 

 completed their groAvth within one year, becoming dead and dry 

 the subsequent season. Sometimes new matter would form near 

 the point of issue of the old one; but this was wholly from the 

 branches, and added nothing to the growth of the foi'mer year. 

 In the case of these Edge Hill sjiecimens, the growth of the 

 excrescence was as regularly continuous as the other woody 

 jiortions of the tree, and seemed to endure while the tree lasted. 

 The first season the excrescences were small, the second as large 

 as marbles, and the third often equalled a walnut in size, while 

 some on the trunks and main branches were as large as an average 

 sized oyster-shell. The minute fungoid organisms that formed 

 these excrescences were usually short-lived ; and their longevity 

 in these instances he considered remarkable. 



On a New Mastodon and Bodcnt. Prof Cope made a commu- 

 nication on the Elephants obtained by himself in New Mexico and 

 Colorado during the past season while attached to the Wheeler 

 Survey. He had obtained Elephas primigenius vav. Columbi from 

 post-pliocene beds at the base of the Zandia mountains, and the 

 Mastodon ohioticus from corresponding beds near Taos. The 

 former species he had also obtained from the valle\' of the South 

 Platte in northeastern Colorado. The pliocene sands of Santa Fe 

 contained numerous remains of a Mastodon which Leidy had re- 

 ferred to his 31. obscurus,^ but which is obviousl}^ a different species, 

 and being without name, Prof. Cope proposed to call it M. produc- 



> Report of Geolog. Surv. Terrs., Vol. I. 4to., p. 235. 



