The Fresh Water Fishes of the Island of Formosa. 295 



Genus Rhinogobius Gill. 



1859. Rhinogobius Gill, Proc. Ac. Nat. Sci. Philad., p. 145. (Type Rhinogobius 

 siinilis Gill.) 



Body oblong, compressed. Head oblong, not much compressed. 

 Eyes high, anterior, close together; opercles unarmed. Mouth 

 moderate, the lower jaw unusually short. Teeth on jaws only; conical, 

 ill few or several series, those in the outer row enlarged; no large 

 canines; tongue usually truncate. Isthmus broad. Shoulder-girdle 

 without fleshy "flaps or papill?e. Skull depressed, abruptly widened 

 behind the eyes and without distinct median keel. Scales moderate 

 or large, ctenoid, permanently covering the body; cheeks naked; 

 opercles naked, or scaled above only; belly generally scaly. Dorsal 

 with six rather weak spines; pectoral well-developed, the upper rays 

 without free or silk-like tips; ventrals completely united, not adnate 

 to the belly; caudal lin usually obtuse. (Jordan & Snyder.) 



Distribution: Philippine Islands; Formosa; China; Corea; Japan; 



North America. 



Synopsis of the Formosan Species. 



I. Opercles entirely naked. 



a. Nape with a naked area. 



b. Dorsal spines filamentous. 



c. Scales about thirty-six; head with many raucous pores. taiwanus. 

 bb. Dorsal spines not filamentous. 



c. Scales thirty-six to thirty-eight; head without mucous pores. 



candidius. 



cc. Scales twenty-nine; head without mucous pores formosaniis. 



aa. Nape closely scaled. 



b. Scales about twenty-nine; dorsal spines not filamentous; teeth in two 



series giurinus. 



bb. Scales about twenty-eight; dorsal spines not filamentous, teeth in 

 villiform band, lower jaw with two canine teeth on each side. caniniis. 



67. Rhinogobius candidius (Regan). 



1908. Ctenogobiiis candidius Regan, Ann. Mag. Nat. Hist. (8), I, p. 153; Lake 

 Candidius, Formosa. 



Head 3.77 in length; depth 5.5; caudal peduncle 2. 11 in head; eye 5; 

 interorbital space 4.75; snout 2.71; D. VI, 9; A. 9; P. 20; thirty-six 

 scales in a lateral series, ten scales between origins of the second dorsal 

 and anal; gill-rakers 3 -|- 6. 



Body robust, a little deeper than wide; caudal peduncle compressed; 

 head slightly depressed; snout rather long and sharp; mouth terminal, 

 a little oblique, its angle not reaching a vertical through the anterior 



