530 PROCEEDINGS OF THE NATIONAL MUSEUM. vol. xxv. 



Tetnujonoptrus Bleeker, Rev. Famille Cheetodontoides, 1877, p. 52 {Mriaha^; 



scales below in horizontal series; spinous dorsal not more than half longer 



than soft) . 

 Cfurtodonfop^ Bleeker, Rev. Famille Chietodontoides, 1877, p. 53 (scales on lower 



parts in ascending series). 

 Hemichtrlodon Bleeker, Rev. Famille Chjetodontoides, 1877, p. 53 {capistratus; 



scales b'ilow running downward and backward, forming an angle with those 



above ) . 

 Lcpkhchivtodon Bleeker, Rev. Famille Chpetodontoides, 1877, p. Hi {uni^iactda- 

 lm; scales anteriorly much enlarged). 

 Gonochivtndon Bleeker, Rev. Famille Cluetodontoides, 1877, p. 54 {triangulniii; 



body very deep; the base of posterior half of soft dorsal and anal vertical). 

 Oxychaiodoti Bleeker, Atlas Ichth. Chiet., 1877-78, p. 51 {Uiieolata.s; scales very 



large, snout pointed). 

 Chxtodon Jord.\n and Gilbert, Synopsis, 1883, p. 614 (restriction to capidratus). 

 Anisochsciodon Klunzinger, Fische des Rothen Meeres, 1884, p. 54 {auriga). 



Body .short, deep, very strongh^ compressed, especially above and 

 behind; head small, compressed, almost everywhere scaly; mouth 

 very small, terminal, the jaws provided with long, slender, iiexil)]e, 

 bristle-like teeth; vomer sometimes with teeth; preoperculum entire 

 or nearly so, without spine. Dorsal tin single, continuous, not notched, 

 the spinous part longer than the soft part, of 12 or 13 spines, the spines 

 not graduated, some of the middle ones being longer than the last; last 

 rays of soft dorsal usuallj' rapidl}^ shortened, some of them occasion- 

 ally filamentous; caudal peduncle short, the caudal tin fan-shaped; anal 

 similar to soft dorsal, with 3 strong spines. Bod}- covered with rather 

 large ctenoid scales, somewhat irregidar in their arrangement; the 

 lateral line curved, high, parallel with the back. Gill-openings rather 

 narrow, the membranes narrowh" joined to the isthnuis; l)ranchioste- 

 gals 6. A very large genus of singular and beautiful tishes, abounding 

 in the tropical seas, especially about volcanic rocks and coral reefs; 

 most of them have the body crossed by transverse black bars. They 

 are all very active, feeding on small animals. 



[xaiTjf^ bristle; oSovs^ tooth.) 



a. Linophora: Rows of scales and dark stripes on anterior part of Ijody sloping 



downward and forward, meeting posteriorly almost at a right angle with 



similar rows and stripes running downw^ard and backward; a black ocular bar; 



dorsal rays XII, 23 to XIII, 25; anal rays III, 20 to 25; scales about 45. 



b. Dorsal with a soft ray in front produced in a filament; soft dorsal with a black 



ocellus setifer, 7. 



bb. Dorsal without produced soft ray; no dorsal ocellus ragabiindus, 8. 



aa. Rows of scales of lower part of body horizontal or nearly so; no lines meeting 



at a sharp angle; scales about 45. 



c. Ch^todontops: Rows of scales on lower parts in series ascending behind; 



a dark ocular bar, but no crossbar on body; dark streaks on sides, 



forked at their tips; no ocellus; ventrals yellow; D. XII, 23; A. Ill, 20. 



rullaris, 9. 



cc. Rows of scales nearly horizontal, not emphasized by longitudinal streaks. 



d. Rabdophorus: Ocular regioia with a distinct crossbar. 



e. Anal rays about III, 21; dorsal rays, XII, 25; soft dorsal with a black 



ocellus; sides with faint brown crossbars modestuf<, 10. 



