154 



BY MESSES. E. M. JOHNSTON AND A. MORTON. 



remains of Acrolepis Hamiltoni, recently described by us in 

 the Proc. of the Royal Soc. of Tas. (1889). The species here 

 described is much better preserved, and though closely allied 

 to the former it is very distinct. The chief differences are 

 the greater prolongation of the sub-caudal fin, giving greater 

 symmetry to the caudal fork ; the greater number of scales 

 or plates in the lateral and transverse series ; and also the 

 relatively greater development of the vertical fins. 



The ornamentation of the scales or plates, although of the 

 same character, also appear to be much finer. The position 

 and relative dimensions of fins also differ to some extent. 



Good photographs have been taken of the two sections 

 disclosed by the splitting of the rock in which the specimen 

 was imbedded. 



Along with these are given magnified views of the under 

 and upper surface of the scales or plates, and also an enlarged 

 view of the dorsal fin, showing the subdivided extremities of 

 rays. The fine series of fulcral scales can be discerned 

 forming a serration along the anterior margin of dorsal fin. 

 There is a probability of a larger number of these interesting 

 fish remains being obtained when operations in certain 

 quarries are again carried out. 



