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those which more especially distinguished Agassiz’s conception of 
“ Amblypterus punctatus” from his A. nemopterus with which he 
contrasted it as occurring in the same beds, it seemed to me more 
appropriate to relain his name u punctatus" for the species of which 
these peculiarities are characteristic. For the other I propose the 
name Elonichthys intermedins ; it is very closely allied both to E. 
nemopterus and E. striolatus, and will be described in my next com- 
munication on the fossil fishes of the Edinburgh district. 
The peculiar dentition of Gonatodus was, however, first correctly 
described by Mr E. Walker* in a fish from the oil shales of Pitcorthie, 
Fifeshire, to which he gave the name of Amblypterus anconocech- 
modus } the horizon in which it occurred being probably that of the 
Burdiehouse Limestone. Mr Walker’s fish undoubtedly belongs to 
the same genus with that described above, and may possibly he 
the same with G. punctatus — if not, it is certainly very closely allied, 
— but I have had no opportunity of instituting a comparison by 
means of actual specimens. Mr Walker, however, makes no men- 
tion of punctures as a scale ornament, and his figures represent the 
entire surface of the scale covered — as he says in the text — “ with 
fine striae which run parallel with the anterior and lower margins,” 
and “are more conspicuous on the scales of some specimens than on 
those of others.” f Eegarding the arrangement of the teeth in the 
lower jaw, Mr Walker also states that they “ are placed alternately 
one close to the outside margin, the next to it is fully half its own 
thickness farther in, and so on the whole length of the bone,” — an 
appearance of which I have observed some slight indications in 
G. punctatus , but not with the regularity described. 
Geological Position and Locality. — The specimens from which the 
above description of Gonatodus punctatus has been drawn up are in 
the Museum of the Eoyal Society of Edinburgh and in the private 
collection of the author. They are all preserved in nodules of clay 
* “On a New Species of Amblypterus and other fossil fish remains from 
Pitcorthie, Fife.” Trans. Edin. Geol. Soc. vol. ii. pt. 1 (1872), pp 119-124. 
t In the Wardie specimens the scales appear for the most part dull, and deli- 
cately striated all over ; this is, however, internal structure , not external sculp- 
ture, and is due to the flaking off of the external ganoine layer. When this 
is preserved in situ, as it is here and there in many specimens, the surface of 
the scale is brilliant, largely punctured, and the appearajice of striation more 
or less limited or obsolete, as already described. 
