1, 



2. Suborder Cyprinoidea. 



(Eventognathi Gill). 



Skin with cycloid scales, exceptionally naked. Parietals not 

 united with supraoccipital, distinct from each other by median 

 suture or by a fontanel. Mouth more or less protractile, toothless. 

 Maxillaries generally excluded by the intermaxillaries from 

 the border of the mouth. Barbels present or absent. The 

 maxillary barbel not supported by the maxillary as in Silu- 

 roidea. No adipose fin. Symplectic and opercular bones all 

 present. Inferior pharyngeal bones falciform, parallel with the 

 branchial arches, armed with mostly large and specialized teeth. 

 Branchiostegals 3. Pseudobranchiae nearly always present. 

 Anterior vertebrae more or less distinct. Ribs mostly sessile. 

 No parapophyses in the thoracic region. Rays of fins articulated, 

 the segments of the second and third dorsal ray may coossify 

 and form a spine consisting of two coossified halves. None 

 of the pectoral rays are ossified. Lateral line nearly always 

 present and complete. 



Key to the indo-au stralian families of the 

 suborder of Cyprinoidea. 



1. Pectoral and ventral fins horizontally inserted, the 

 former generally with several of their outer and some- 

 times of their inner rays simple. No movable spine 



before or below eye. At least 6 barbels Homalopteridae p. 2. 



2. Pectoral and ventral fins not horizontally inserted!, * ^ ; > 

 only one of their outer rays simple. 



a. A simple or bifid movable spine may be present -. \ > ;..' *;-* 



before or below eye, which has a free orbital margin 

 or is covered by skin. Mouth inferior, with 6, 8 or 



more barbels Cobitidae p. 21. 



b. No movable prae- or subocular spine; eye with a 

 free orbital margin ; mouth anterior or inferior 

 with never more than 4 barbels Cyprinidae p. 43. 



INDO-AUSTRALIAN FISHES III. i 



