34 



versant with the fixed relations of osteological and dental characters, 

 that the three corresponding parts of three Pterodactyles for the first 

 time discovered, should be appropriated to three distinct species, I 

 have no other alternative, in obedience to the indications of nature, 

 than to adopt such determination*. 



2. Description of two nev^^ genera and some new species 

 OF Scutellid^ and Echinolampid^ in the Collec- 

 tion of the British Museum. By John Edward Gray, 

 Esa., F.R.S., P.B S. etc. 



The collection of the British Museum is extremely rich in species 

 of recent Echinoids, and fortunate in possessing long series of different 

 ages of several of the species. 



Having been recently occupied in arranging and forming a cata- 

 logue of these animals, I transmitted to the ' Annals of Natural Hi- 

 stoiT ' for February a description of several genera and species of 

 SpatangidcB. 



MM. Agassiz and Desor ha-\aug recently published, in the Mono- 

 graph of Echini and other papers on these animals, all the species of 

 these two families then known to them, and as they had every facility 

 for examining the British ]\Iuseum specimens, the species now to be 

 described are but few in number. 



Fam. 1. Scutellid^. 

 Genus Echinanthus. 



Among the species which have the base concave, of which E. ro- 

 saceus may be considered the type, are to be added — 



1. Echinanthus Australasia. 



Vent beneath, at a little distance from the edge ; back very convex 



* The same criticism or objection may be otFered to the conclusions in the text, 

 as the following one, which was called forth by my determinations of the species 

 of Balcenodon found in the red crag. " The specimens exhibited by Prof. Hens- 

 low were only eleven in number ; so that, without allowing anything for the cir- 

 cumstance of each whale having hvo tympanic bones, and the probability of some 

 of the above being in pairs, we have the first twelve determinable cetaceous bones 

 discovered in the red crag appropriated to no less thanjive species. I have no pre- 

 tensions to call in question the decision of Prof. Owen upon osteological grounds, 

 but I must own that I am disposed, upon the doctrine of chances, to consider it 

 hardly probable that these determinations are accurate." — Searles V. Wood, Feb. 

 16, 1844, London Geol. Journal, p. 35. Ihe fifth species is a gratuitous addition 

 to the four described by me, the determinate characters of which have been con- 

 firmed by numerous additional discoveries. Mr. Wood should have remembered, 

 before he attempted to discredit the determinations from anatomy, and to substi- 

 tute the numerical test, that the second mammalian fossil from the oolite, although 

 a lower jaw, like the first, was of a difi"erent species, and that of five subsequently 

 discovered unequivocal mammalian remains from Stonesfield, all are parts of the 

 lower jaw, whilst two of them demonstrate a third species. Very improbable this 

 to him, on the doctrine of chances; but only showing, as Sir Charles Lyell has 

 remarked, " the fragmentai7 manner in which the memorials of an ancient terres- 

 trial fauna are handed down to us." 



