42 CALIFORMIA ACADEMY OF SCIENCES. 



Arius Bleeker, Ichthyol. Arch. Iiidici Siluri, 1858 

 (m'ius). 



Arius Bleeker, Nederl. Tijdschr. Dierkunde, i, 1863, 

 91 (grandicassis). 



Sciades Miiller & Troschel, Horae Ichthyol. ill, 8, 1849 

 (sp.) 



Sciades Bleeker, 1. c. (eni'ph.ysehis) not Sciades Blkr., 

 Ichthyol Arch. Indici Siluri, 62 (jnctus). 



Ariodes Miiller & Troschel, 1. c. iii, 9, 1849 (sp.) 



Ariodes Bleeker, Ichthyol. Arch. Indici Siluri, 62, 

 1858 (arenarius). 



Hexanematichthys id., 1. c. 61 (sundaicus). 



Cephalocassis id., 1. c. 62 (melanochir). 



Netunna id. 1. c. (nasuta). 



Guiratinga id. 1. c. (commersonii). 



Sciadeicldliijs id. 1. c. (emiiihysetus) not Sciadeichthys 

 Blkr., Nederl. Tijdschr. Dierkunde, i, 1863, 99 (pic- 

 tus)= Sciades. 



Selenaspis id. 1. c. (herzhergii). 



Hemiarius Bleeker, Nederl. Tijdschr. Dierkunde, i, 

 1863, 90 (stormi). 



Pseudarius id. 1. c. 1863, 91 (arius)= Arius Blkr., 1858. 



Leptarius Gill, Proc. Philad. Acad. Nat. Sci. 1863, 170 

 (doiuii). 



Notarius Gill, 1. c. 171 (grandicassis). 



Cathorops Jordan & Gilbert, Bull. U. S. Fish Com. 

 1882, 39 (hypopldhalvfius). 



This genus is composed of many well-marked sub- 

 genera, and it is, therefore, difficult to define it other- 

 wise than by describing the sub-genera. 



The species of this genus are usually marine; many 

 are, however, found in the rivers of South America. It 

 is found in all continents but Australia. 



