tp:rtiary fishes. 
17—257 
species, wliich inhabit the warmer seas. Numerous fossil species have been indicated 
from the lower and middle tertiaries, of which the following are the most important. 
D. tetmispinus, Ag,^ from the eocene of Monte Bulca, is of comparatively small 
dimensions ; B. erinaceus, Ag,^ is founded on specimens now in the British Museum, 
and is of exceedingly small size ; D. scillce, Ag,® from the tertiaries of South Italy and 
Malta is of considerably larger size, and has the edges of the dental lamellae 
crenulated^ ; some of the type teeth of this species are in the British Museum, and 
the specimens from the miocene of Malta noticed by Leith-Adams® are also in the 
same collection, and appear specifically identical. Another species has been recorded 
by Prof. Leidy from the tertiary of N. America as D. vetus^^ but is insufficiently 
^described. 
Species. Diodon foleyi, nobis? 
(From the eocene of Bamri Island. J 
History . — The type specimen has been already described by the present writer 
in the passage cited. 
Dental plate . — The worn dental plate on which this species is founded is 
represented in plate XXXV. figs. 10, 10a; it was obtained many years ago by 
Captain Foley from beds which are probably of eocene age in Rdmri Island, off the 
Arakan coast. The structure of the specimen indicates without doubt its generic 
position ; it is of large size, and characterized by the crenulation of the external 
borders of the component lamellse, and the concavity of the worn surface. 
Affinities . — Compared with the dental plate in a skeleton of D. hystrix in the 
British Museum measuring about twenty inches in length, the fossil indicates a 
considerably larger individual, and is distinguished by the concavity of its wear. 
The geological age of the specimen leaves little doubt as to its distinctness from all 
living species. D. erinaceus and D. tenuispinus are far inferior in size to the present 
form, and the writer cannot identif)^ the latter with D. scillce : it cannot be compared 
with D. vetus, owing to the absence of a figure. 
Although it cannot be certainly affirmed that the present specimen is specifically 
distinct from all other forms (if indeed the dental plate alone affords sufficient 
grounds for specific distinctions), yet such is probably the case, and the provisional 
name of D. foleyi may accordingly be retained. 
I “ Poissons Possiles,” vol. II. p. 275. 2 £oc. cit. 3 Zoo. cit. 
4 Vide Pictet “ Traite de Paleontologie,” 2nd ed. vol. II. p. 123 (1854), 
5 Vide Leith- Adams ‘ Quart. Journ. Geol. Soc.’ vol. XXXV. p. 529 (1879). 
6 ‘ Proc. Ac. Nat Sci. Philad.’ vol. VII. p. 397 (1855— vol. dated 1856). 
<■ ‘ liec. Geol. Surv. Ind.’ vol. XIII. p, GO (1880). 
E 
