31. CYPEINID^. 147 



R. Lateral line iucomplete. 



Hemitremia, 83. 



RR. Lateral line complete Cliola, 84. 



PP. Teeth 2, 4-4, 2. 



S. Lateralliue complete.. MiNNiLUS, 85. 

 SS. Lateral line incomplete; scales 

 small.PKOTOPORUS, 86. 

 00. Mandible, interopercle, and 8iil)orbital witli 

 couspicnons, externally 

 visible, cavernous cham- 

 bers; teeth 1, 4-4, 0. 



Ericymca, 87. 

 NN. Lower jaw with the lip developed as a fleshy 

 lobe on each side ; teeth 

 4-4 ; dorsal anterior. 



PllENACOBIUS, 88. 

 LL. Maxillary with a small barbel at its extremity. 



U. Premaxillaries not jirotractile ; 

 teeth 2, 4-4, 2; scales 

 small ; dorsal jiosterior, 

 Rhinichthys, 89. 

 UU. Premaxillariesiirotractile. 

 V. Teeth 4-4, or 1, 4-4, 1, or 1, 4-4, 0. 

 W. Scales very small ; dorsal 

 posterior. 

 X. Lateral line complete. 



Agosia, 90. 

 XX. Lateral line incomplete. 

 Apocope, 91. 

 WW. Scales large; dorsal me- 

 dian; lateral line com- 

 plete. 



Ceratichthys, 92. 

 VV. Teeth 2, 4-4, 2. 



Y. Head convex above ; 

 teeth without grinding 

 surface ..Couesius, 93. 

 YY. Head flattened above ; 

 teeth with grinding sur- 

 face.. -Platygobio, 94. 

 KK. Teeth in the main row 5-5 or 4-5. 



Z. Maxillary with a bar- 

 bel; premaxillaries i)ro- 

 tracti le. 

 a. Teeth hooked, none of them molar ; teeth in the lesser row 2. 

 b. Caudal fin synmietrical, its rudimentary basal rays not greatly developed. 



c. Barbel minute, lateral ; teeth without grinding surface Semotilxis, 95. 



cc. Barbel terminal; teeth with grinding surface Symmetrurus, 96. 



bi. Caudal fin unsymmetrical, the upjier lobe much the longer, tlio basal caudal 



rays greatly developed Pogoniciithys, 97. 



an. Teeth partly molar, much enlarged, obtusely truncate, lesser row with 2 teeth ; 



scales small Mylociiilus, 98. 



ZZ. Maxillary without 

 barbel. 

 d. Upper jaw not protractile ; 2 or 3 teeth modified, molar ; teeth 2, 5-5, 2, or 2, 

 5-4, 2 Mylophakodon, 99. 



