36 Dr. Albert Giinther on the 



VIII. — A ContrUndion to the Fauna of the River Tigris. By 

 Dr. Albert Gunther, F.E,.8., Assistant Keeper of the 

 Zoological Department, British Museum. 



[Plates Vin. & IX.] 



Dr. Siiarpey, F.E.S., has presented to the Trustees of the 

 British ]\Iuseum a collection of fishes made by his nephew, 

 William Henry Colvill, Esq., at Bagdad. This collection 

 was the more welcome as we have hitherto experienced con- 

 siderable difficulty in obtaining zoological specimens from 

 Mesopotamia, and as the examples sent were in an excellent 

 state of preservation and of a fair size. On a close ex- 

 amination of its contents it proved to add considerably to our 

 knowledge of the fishes of the Trigris, as will be seen from 

 the following notes. 



Perhaps the most interesting specimen of the collection is 

 a beautiful example, 2^ feet long, of Carcharias gangeticus 

 (M. & H.). It was previously known that this species enters 

 freely the large rivers of India, and tliat it inhabits the fresh 

 waters of Viti Levu. But it is a matter of surprise to find a shark 

 in a river at such a distance from the sea, Bagdad being about 

 350 miles from the Persian Gulf in a straight line, and many 

 more if all the windings of the river are taken into considera- 

 tion. It would be a point of great interest to ascertain whether 

 this fish spawns in the river (as it actually does in Viti Levu, 

 where it inhabits a lake shut out from the sea by a cataract), 

 or whether it descends to the sea for that purpose. 



Of Acanthopteiygians, there is only one adult example of 

 the eel-shaped JIastacembelus aleppensis in the collection: it has 

 thirty spines ; and its coloration agrees with the figure given 

 by Heckel. 



Of Siluroids there are two species, both of which appear to 

 be common in the Tigris. The first is the Silurus trtostegus 

 described and figured by Heckel ; the second is an undescribed 

 species of Macrones, with which I associate with great pleasure 

 the name of its discoverer : — • 



Macrones ColvilUi. Plate VIII. 



Much more slender than M. aleppensis, to which it is closely 

 allied. 



D. 1/7. A. 12. 



The height of the body is contained six and a half times in 

 the total length (without caudal), the length of the head five 



