298 



the margin of the zone they occupy as their outcrop. It is 

 obvious that a depression of the cretaceous region, such as 

 would cover the present deposits with a deep sea, would have 

 likewise overspread the low Gneissic hills to the N. VV. of the 

 Delaware, which present no traces of having ever been sub- 

 merged during the cretaceous or any secondary period. 



Mr. Ayres remarked, that of those genera of Echino- 

 derms, which Mr. Forbes regarded as deep sea genera, two 

 or three are found in North America in water not two hun- 

 dred feet deep. Terebratula, which has been generally 

 regarded as only an inhabitant of very deep water, and 

 whose structure has been described as admirably adapted 

 to the depth at which it has been found, and which Prof. 

 Owen has demonstrated cannot exist at a depth of less 

 than two or three hundred fathoms, exists at Eastport, Me., 

 in water so shallow that it can be taken by hand. In the 

 same locality and position, Radiata are found which have 

 heretofore been thought to be only inhabitants of deep 

 water. Some of Mr. Forbes's genera are also found in less 

 than ten fathoms of water. 



Dr. Kneeland exhibited a tarso-metatarsal bone of Palap- 

 teryjc, belonging to President Hitchcock, with the view of 

 confirming the opinion expressed by him at a former meet- 

 ing, that the specimen belonging to the Society indicates a 

 new species of this genus. 



The specimen exhibited was no doubt P. ingens^ as it agrees 

 remarkably with the dimensions given to it by Owen. It was 

 interesting as having a perfect upper extremity, from which Dr. 

 N. B. Shurtleff had moulded the portion wanting in our specimen. 

 It also had, just where it ought to have it, according to Owen, 

 and just where our specimen has it, a rough articulating surface 

 for a fourth, or hind toe ; it can hardly be believed that this is 

 also an accidentally abraded surface, as some thought of our 

 specimen. 



That ours belongs to a new species he was confirmed in his 

 belief from the examination of this bone of P. ingens^ and the 



