269 
of Edinburgh, Session 1876-77. 
are in the collection of the Boyal Society of Edinburgh ; while the 
third, collected by Dr Buckland, and contained in the Oxford Uni- 
versity Museum, was forwarded to me with great liberality by Pro- 
fessor Prestwick. A comparison of these specimens with a series 
of entire fishes from the Wardie beds establishes the fact, that the 
Amblypterus punctatus of Agassiz was founded upon fragments of 
two distinct species, the specimen with the head, but without the 
hinder part of the body, being even generically distinct from the 
other two, which display the hinder part, but without the head,— 
the fishes to which they respectively appertain differing not only 
in dentition, but also in many other particulars connected with the 
head, the scales, and the fins. 
The peculiar form and arrangement of the teeth in the first of 
these render necessary the institution of a new genus, to which I 
have given the name Gonatodus * These teeth were somewhat in- 
correctly described by Agassiz as being “ en cones obtus,” this 
appearance in the specimen he examined being due to their being 
there only seen in antero-posterior vertical section, their pecu- 
liar flexures and pointed apices being invisible ; their being dis- 
posed “sur plusieurs rangdes ” seems also to be an error as far as 
the mandibles and maxilla are concerned, though probably there 
were additional teeth on the margin of the palate. Perfect 
examples of the species to which the other two type specimens 
belong show that the teeth are in it acutely conical, incurved, and 
of different sizes, large and small, and that in these and other 
respects the fish is closely allied to the Amblypterus nemopterus , 
Palceoniscus striolatns , and P. Robisoni of Agassiz, along with 
which forms it is, in my opinion, referable to the genus Elonichthys 
of Giebel.f It now, however, becomes a question for which of 
these two fishes the specific term “ punctatus ” should be retained. 
Now, although the enlarged representations of scales given by 
Agassiz (Pois. Foss. Atlas, vol. ii. tab. 4 c. figs. 6 and 7) are taken 
from the second species ( Eloniclitliys ), yet the term is indeed 
applicable to both, and as the characters of the head and teeth are 
* yow , knee; and odovs, tooth. 
t The reasons for removing these forms from the genera Amblypterus and 
Palceoniscus, and uniting them with Elonichthys, will be given in my next 
communication. 
