New Fish from Mesozoic Rocks of Victoria. 149 



The exact position of the specimen in the zoological series, 

 owing to the imperfect nature of the remains, is somewhat 

 difficult to fix. There seem to be only two families which need 

 to be taken into consideration as afibrding a possible resting place 

 for our specimen, namely Palaeoniscidae and Chondrosteidae. 



In the latter family only one genus, Chondrosteus, is at aU 

 well known, and from this our specimen differs in three par- 

 ticulars, namely, it has fulcrals on the dorsal, the dorsal is 

 partly over the anal, and the neural arches are more completely 

 ossified than in Chondrosteus.^ 



These characters might perhaps be regarded as merely generic, 

 and as our fish is naked except on the upper caudal lobe, where 

 thick rhombic scales occur, is devoid of ribs, and agrees in general 

 build with Chondrosteus, it may possibly find its resting place in 

 the same family. 



As regards its relationship with the Palaeoniscidae we again 

 find no characters as laid down by Smith "Woodward" for this 

 family which would prevent its inclusion in it. "When, however, 

 we come to its generic position there is no place into which it 

 will tit. Comparing it with our Australian genus Coccolepis, 

 there is the difference in squamation of the body and in the 

 presence of the large fulcral scales both on dorsal and caudal, as 

 well as the difference in the position of the dorsal which forbid 

 their close association. 



Leptolepis, Agassiz, 1832. 



Leptolepis crassicauda, n.sp. 



Distinguishable from the other described Australian species of 

 the genus by the great comparative width of the pedicel of the 

 tail which is one half of that of the body at the front end of the 

 dorsal. The position of the fins is also somewhat different, the 

 dorsal arising slightly in front of the ventrals and not behind 

 them; while the anal arises a little behind the mid-point between 

 the posterior end of the ventral and the caudal. The observable 

 characters agree closely with those of the genus as detailed by 



1 A. Smith Woodward, Cat. Fossil Fishes in Brit. Mus., pt. iii., p. 27, pi. i., f. 4. 



2 L. cit., Part II., p. 426. 



3a 



