78 WHITEAVES ON FOSSIL FISHES FEOM 



graph, whether the Canadian species is identical with it or not, it seems safer to give the 

 latter a provisional name, until the true specific relations of each shall have been ascer- 

 tained by a direct comparison of specimens from both sides of the Atlantic. 



A second species of Glyptolepis, apparently of the type of G. hptopterus, Agassiz, 

 appears to be indicated by two large isolated scales collected by Mr. R. W. Ells in 1880. 

 These scales, which are nearly an inch in diameter, are ornamented with the wavy costse 

 and semilunar or crescentic area of backwardly directed points peculiar to the genus. It 

 is, however, possible that they may have belonged to large and adult examples of 

 G. Quebecensis, and that the specimen upon which that species is based may be a A^ery 

 immature individual. 



EusTHENOPTERON FooRDi, WliUeaves. 



(Plates V, fig. 5, VI and YII.) 



Eusthenopteron Foordi, Whiteaves, 1881. Can. Nat. and Quart. Journ. Sc, N. S., Vol. X, 

 p. 30. 



The following are the original diagnoses of this genus and species : — 



" Eusthenopteron,' G-en. Nov. 



" Generic Characters. — Dermal plates of the head densely and irregularly corrixgated 

 externally, the corrugations varying in size in different parts of the same plate, but rarely 

 or never coalescing with each other so as to form a complete network. The larger 

 corrugations have a tendency to become tubercular. Teeth, at least the smaller ones, 

 compressed-conical, with a sharp, cutting edge on each side. Scales of the body, cycloid, 

 imbricating ; their exposed sixrfaces marked either with minute, close-set, irregular, 

 radiating, tubercular ridges, — or more rarely with a semi-circular area of concentric rows 

 of small, distant, isolated tubercles, upon a surface ornamented with exceedingly fine, 

 wavy, radiating lines. Dorsal fins two, separated by an interval about equal in length 

 to the height of the body between them.^ Pectoral fins unknown. Ventrals small, short, 

 broad and placed a little behind the first dorsal. Anal fin large and broad, placed 

 opposite to the second dorsal. Caudal fin also large and broad, heterocercal, with an 

 unusually well developed upper lobe. 



" Vertebral centres not ossified ; neural and hsemal spines and interspinous bones 

 well developed and completely ossified. Neural and haemal spines anterior to the second 

 dorsal and anal, and for a short distance behind them, blade-like and flattened, with more 

 or less acute margins. Neural spines of the upper lobe of the tail simple, much elongated, 

 subcylindrical and slightly curved. Fin rays of the lower lobe of the tail supported by 

 nine or ten osselets, each of which is articulated by a transverse joint to one of the modi- 

 fied hœmal spines. On the anterior or lower side of this lobe and nearest to the anal fin, 



' From ciwdenric, stout, and nrepov, a fin, in reference to the strongly developed [bony supports of the] anal and 

 second dorsal- 



^ The interval between the first and second dorsal is now known to have been about equal to one-half the 

 height of the body between them. 



