2678 Bulletin 4.7 , United States National Museum. 

 1051. CITHARICHTHYS,* Bleeker. 



(WHIFFS.) 



Citha-richthys, BLEEKER, Comptes Rendus Acad. Sci. Amsterd., xm, Pleuronectoklei, (5 



1862 (cayennensis = spilopterus) . 



Orthopgetta, GILL, Proc. Ac. Nat. Sci. Phila. 1862, 330 (sordidus). 

 Metoponops, GILL, Proc. Ac. Nat. Sci. Phila. 1864, 198 (cooperi= sordidus). 



Eyes and color on the left side. "Body oblong; mouth of the large type, 

 but comparatively small, with 1 series of small, sharp teeth in each jaw; 

 no teeth on vomer or palatines. Gill rakers moderate, slender. Dorsal 

 fin beginning just in front of eye; all the fin rays simple; ventrals of 

 colored side on the ridge of the abdomen ; no anal spine ; caudal fin con- 

 vex or double truncate behind; none of the fins produced. Scales thin, 

 deciduous, slightly ctenoid. Lateral line nearly straight, simple. Lower 

 pharyngeals separate, each with a single row of teeth. Vertebra 30 to 

 40. This genus includes small flounders of weak organization, espe- 

 cially characteristic of the sandy shores of tropical America. The sub- 

 genus Orthopsetta includes species of more northern range and somewhat 

 different form, and especially noteworthy as having an increased num- 

 ber of vertebrae. The two groups intergrade so perfectly that no sharp 

 line of division can be drawn between them. (Citharus, an allied genus; 

 v$, fish a fish which lies on its H$apo$, or ribs; that is, on its side.) 



ORTHOPSETTA (6p06?, straight; ^TTO., flounder): 

 a. Yertebra3 37 to 40; interorbital ridge sharply elevated; the head not closely com- 



pressed ; eyes large ; species of the North Pacific. 

 b. Interocular space concave, scaly, at least behind. 

 c. Gill rakers x + 16 to 18. 



d. Scales 65 to 70 ; dorsal rays 95 ; aiia!77; depth 2. SORDIDUS, 3048. 



dd. Scales 46 to 50; dorsal rays 83 to 87 ; aiial 67 to 70; depth 2g in length. 



FRAGIL1S, 3049. 



cc. Gill rakers x + 10 or 11 ; dorsal rays about 84 ; anal 65 ; scales 50 ; depth 2 



in length. XANTHOSTIGMUS, 3050. 



bb. Interocular space a sharp, naked ridge; dorsal rays 85 to 90; anal 68 to 72; 



scales 55 to 60; head 3| in length ; depth 2. STIGM^EUS, 3051. 



ClTHARICHTHYS: 



aa. Vertebrae 33 to 36; interorbital ridge low and narrow, the head closely compressed. 



Species of the Atlantic or the Tropics. 

 e. Eyes large, 3 to 4 in head. 



/. Head large, 3 to 3J in length. 



g. Interorbital space very narrow, 5 in eye; snout with a spine ; pectoral 



of eyed side elongate, longer than head; maxillary 2J in head. 



D. 91 ; A. 73 ; scales 48. DINOCEROS, 3052. 



gg. Interorbital space very broad, 2 in eye ; snout without spine ; pec- 



toral of eyed side shorter than head ; maxillary 2J in head. D. 



78; A. 62; scales 43. PLATOPHRYS, 3053. 



ff. Head smaller, about 4 in length. 



h. Body comparatively elongate, the depth about 2J in length; mouth 

 very small; the maxillary 3 in head; dorsal rays 83; anal 67; 

 scales 40; eye 4 in head. ARCTIFRONS, 3054. 



* "Aa the name Citharichthys was introduced a short time before that of Orthopsetta, 

 proposed for the Ptettichthys sordidus, and was framed for a species related to that type, 

 that name must be adopted if the O. sordida is not regarded as genericaliy distinct." 



