DAVIS : OSTRA CACANTHUS DILATATUS. 
195 
majority of its congeners that a naturalist might be well 
acquainted with almost all the fossil ganoids and yet not 
recognise a sturgeon as a member of the group, — it will 
not seem difficult to admit the existence of a Teleostean 
among the Devonian ganoids, even though that Teleostean 
should in some, even important, points differ from those with 
which we are familiar." 
It may be somewhat premature, considering the frag- 
mentary nature of the specimen, to express an opinion that 
a fish resembling the Teleostean Ostracion has been found in 
the Coal Measures. The spine and its peculiar attachment, 
however, are totally different from every other form of 
icthyodorulite with which I am conversant, and providing 
the evidence on which Prof. Huxley bases the arguments 
given above is held to be correctly applied, and that the 
oldest Devonian fishes have many points of similarity 
and relationship with the Siluroid family of the Teleosteans, 
the probability of the occurrence of fishes of a somewhat 
similar type during the succeeding carboniferous age is 
rendered at least plausible. I have therefore thought it 
advisable to bring this peculiar fossil to your notice, not with 
any wish to dogmatise on its relation to the modern Ostracion, 
but merely to afford the members of this Society taking an 
interest in fossil fishes an opportunity of thinking on the 
subject, and with the hope that some more perfect specimens 
may soon be discovered which shall place the present one in 
its true position. 
I take the liberty of distinguishing the specimen with 
the generic name of Ostracacanthus* from the resemblance 
of the spine to those of the Ostracion, and adding the 
nomen trivicde, dilatatus, in reference to its wide and dilated 
base. 
* "Oa-rpaKou, a hard shell or testacea, and anavda, a thorn. 
