On some Fossil Fish of the Carboniferous Period. 189 



XXI. — Observations on Mr. McCoy's Paper on some Fossil Fish 

 . of the Carboniferous Period. By Sir Philip de Malpas 

 Grey Egerton, Bart. 



To the Editors of the Annals of Natural History. 



Gentlemen, 

 I HAVE just perused a paper in the Number of your Journal for 

 July last by Mr. M^Coy, in which he proposes a very important 

 alteration of Agassiz^s arrangement of the Ganoid Fishes from 

 the Palaeozoic formations. The passage I allude to is the fol- 

 lowing : — 



*' I provisionally propose to establish a distinct family under the 

 above name {Placodermi), to include those Ganoid fish of the palaeo- 

 zoic rocks having the head and body encased in a series of odd or 

 central, and of subsymmetrical or lateral, bony, variously tubercu- 

 lated plates of large size. It might probably include all the genera 

 described by Agassiz in his ' Monog. du Syst. Devon.^ &c., under 

 the title Cephalaspides, except Cephalaspis, to which that family- 

 name might be retained, the other genera having no obvious affi- 

 nity with it ; in addition to these, the present group will conve- 

 niently embrace the genera Bothriolejns, Aster olepis and Psammos- 

 tens, which, although widely separated from the former by Agassiz 

 and placed by him in his family of Coelacanths, are so obviously 

 and closely allied to some of them (e. g. Chehjophorus, Coccosteus, 

 &c.), that they cannot be separated either by general appearance 

 or any points of structure with which we are acquainted ; while 

 they differ, on the other hand, from the other Ccelacanthi by the 

 body not being covered by imbricating scales/' 



TS^ot having seen the specimens which have induced Mr. M'Coy 

 to propose this new classification, I am unable to form any opi- 

 nion as to whether he is justified or not in making the change; 

 I cannot however allow a charge to be brought against my friend 

 Professor Agassiz, in his absence, of having grouped together 

 genera under the title Cephalaspides, having no obvious affinity 

 with the genus Cephalaspis, and having widely separated genera 

 so obviously and closely allied to some of them, that they cannot be 

 separated either by general appearance or any points of structure, 

 without claiming that in justice to Agassiz, his opinions on this 

 subject may be accorded in your pages the same publicity which 

 Mr. McCoy's observations have already received. The following 

 passage must surely have escaped Mr. M'Coy's memory when 

 he claims to have discovered affinities (supposed to have befin 

 overlooked or disregarded by Agassiz) of sufficient value to jus- 

 tify a re-classification of the Palseozoic Ganoids : — " II y a un 

 rapprochement evident entre les Coccostees et les genres large- 



