NATURAL SCIENCES OF PHILADELPHIA. 37 



Genus XIV. Opistoonema Gill. 



Syn. Clupanodon Lac, partim, Hist. Nat. des Poissons, vol. 



Body oblong oval. Teeth in a longitudinal row on the tongue. Dorsal fin 

 with its last ray filiform. 



Type. Opisthonema thrissa Gill. 

 Syn. Clupanodon thrissa Lac. 



Genus XV. Aladsa (Cuv.) Val. 



Syn. Alosa Cuv. Regne Animal 



Alausa Val. Hist. Nat. des Poissons. vol. xx., p. 389. 



Teeth absent, or only some small and easily caducous ones on the jaws. 

 Scales not pectinated. Dorsal fin over the ventrals. Head of moderate size. 



Type. Alausa vulgaris Cuv. 

 Syn. Alausa vulgaris Val. Hist. Nat. des Poissons, vol. xx., p. 391. 



Genus XVI. Brevoortia Gill. 



Syn. Brevoortia Gill. 



Teeth absent. Scales pectinated on their posterior margins. Dorsal fin 

 nearly over the interval between the ventrals and anal. Head very large. 



Type. Brevoortia menhaden Gill. 

 Syn. Alausa menhaden Val. Hist. Nat. des Poissons, vol. xx., p. 424. 



B. 



Provided with true and spurious anal fins, entirely distinct from each 

 other ; the former of the normal size; the latter with two or more thick and 

 well developed rays. 



Genus XVII. Clupeichthts Bleeker. 



Syn. Clupeichthys Bleeker, Naturkundig Tijdschrift voor Nederlandsch Indie, 

 vol. ix., p. 274, 1855. 



Intermaxillary bones prominent; the lower little longer than the upper, con- 

 spicuous teeth on the intermaxillary, supramaxillary, palatine and pterygoid 

 bones, and in a median longitudinal band on the tongue. 



A single species is found in the rivers of the island of Sumatra.* 



Type. Clupeichthys goniognathus Bleeker. 



Group PELLONA Gill. 



Anal fin elongated, commencing under or anterior to the last rays of the dor- 

 sal, and near the ventrals. 



a. Ventral fins present, and situated anterior to or under the first rays of the 

 dorsal fin. 



Genus XVIII. Pellona Val. 



Syn. Platygaster Swainson, Natural History of Fishes, Amphibians and Rep- 

 tiles, vol. ii. p. 294, 1839. (Not Platygaster Latreille.) 



Ilisha (Gray,) Richardson, Fifteenth Ainual Report of the British Associa- 

 tion. A.S., 



Pellona Cuv. et Val. Hist. Nat. des Poissons, vol. xx. p. 301. 



Body compressed, varying in form; in the typical species, the abdomen is 



*Buchanan Hamilton, in his " Account of the Fishes found in the river Ganges and its 

 branches," p. 236, has described a Clupeoid which has also two fins, the last provided 

 with four rays, but there are said lo be no teeth. It has been referred to a new genus 

 and called Corica sobrona. If it is true that there are no teeth, the species can not be 

 congeneric with Clupeichthys goniognathus. The work of Hamilton is not at present 

 accessible to us. 



1861.] 



