﻿ELONICHTHYS STRIOLATUS. 



57 



becoming more equilateral as we pass backwards, till on the caudal body-prolongation they 

 are small, and, as usual, acutely lozenge-shaped. They are crossed by fine, wavy, 

 branching, and anastomosing striae (PI. VI, fig. 2), which persist over the greater part of 

 the body ; on the tail-pedicle, however, we find the strige tending to become obsolete, and 

 to be replaced, towards the hinder margin of the scale, by small punctures. On the 

 caudal body-prolongation the scales are nearly absolutely smooth, excepting on the large 

 V scales bordering it above, in which the striae persist so far as the specimen extends. 



Observations. — In its dentition, in the relative position and size of the fins, save the 

 ventral, which seems a little smaller in proportion, and in the structure of the fin-rays, 

 this species approaches exceedingly closely the two others already described from the same 

 locality, namely, Elonichthys semistriatus and E. caudalis. It differs, however, from 

 both in the more oblong form of the body and the greater relative depth of the tail- 

 pedicle. The nature of the scale-ornament separates it very distinctly from E. semi- 

 striatus, though in this respect its resemblance to E. caudalis is greater ; the striae, 

 however, are rather more delicate than in the latter Fish, and the pattern slightly different 

 in general aspect. 



Geological Position and Locality. The specimen of Elonichthys oblongus just de- 

 scribed, and the only one which I have seen, belongs to the collection of Mr. John 

 Ward, E.G.S., of Longton, and is from the shales accompanying the " Knowles 

 Ironstone" of Fenton, Staffordshire. It is therefore as yet only known from the Coal- 

 measures. 



4. Elonichthts striolatus, Jgassiz, sp. Plate VII, figs. 4 — 15. 



Pal^oniscus striolatus, Jgassiz. Poissous Poss., t. ii, pt. I, p. 91 ; Atlas, t. ii, tab. 



10 a, figs. 3 and 4, 1835. 

 — — Morris. Catalogue of British Fossils, p. 337, 1854. 



Description .The most perfect example of this species which I have seen is con- 

 tained in the Hugh Miller Collection, Edinburgh Museum of Science and Art, and is 

 represented in PI. VII, fig. 4. It measures 5| inches in length by 1£ in depth at 

 the commencement of the dorsal fin. The length of the head is contained four times in 

 that of the entire fish up to the bifurcation of the caudal fin, and four times and three 

 quarters up to a point opposite the extreme termination of the upper lobe ; the greatest 

 depth of the body is contained nearly four times in the total, and is equal to two and 

 a half times the depth of the tail-pedicle. 



The original of Agassiz's figure, preserved in the Museum of the Royal Society of 

 Edinburgh, is a fish o'f nearly the same size as the above, but its form is a little distorted 

 and its scales considerably broken up. Another specimen in the Edinburgh Museum, 

 8 



