\A. I'LATVSTETHUS. ^91 



14. PLATYSTETHUS. 



Body oblong, compres.sed, with smooth scales of modei'atc size, 

 which have the edge minutely serrated ; cleft of the mouth narrow, 

 oblique; snout obtuse, of moderate extent. Prajopcrcular margin 

 entire. The first dorsal continuous, with eight stout sjjincs ; the 

 second and the anal arc much more developed, and can be received 

 in a scaly sheath ; finlets none ; anal spines three. Pectorals and 

 ventrals rather short. Minute teeth in the jaws ; palate smooth. 

 Branchiostegals five or six. . . 



Norfolk Island. 



1. Platystethus cultratum. 



SciiBna cultrata, Forstcr, 



Cichla cultrata, lil. Sclui. p. 343. 



Seriola cultrata, Richanls. Ann. l^ 3Iuij. Nat. Hist. xi. 1843, p. 109. 



B. 5-6. D. 8|Jj. A.|. L. lat. 60. L. transv. 5/14. Vert. 25. 



Uniform silvery. 

 Norfolk Island. 



a. Type of the species. Norfolk Island. Cook's Voyage. 



b. Bad state. Norfolk Island. From the Collection of the Royal 



College of Surgeons. 



Description. — The body is oblong and compressed, the edge of the 

 abdomen rather sharp. The lateral portion of the breast is fiat, and, 

 in consequence of the high position of the pectoral fin, rather elevated. 

 The greatest depth of the body is below the origin of the soft doi'sal, 

 and one-fourth of the total length. The length of the head is 5^ in 

 the total. The snout is 1 1 the diameter of the eye, which is 4| in 

 the length of the head. The cleft of the mouth is very oblique, and 

 the lower jaw projects slightly beyond the upper. The maxillary is 

 broad and rounded posteriorly, and reaches to the vertical from the 

 anterior margin of the eye. The nostrils are situated on the upper 

 side of the snout, and nearer to the eye than to the extremity of the 

 snout. The interorbital space is, like the crown, smooth and convex, 

 and its width is much more than the diameter of the orbit. The eye 

 is situated high up the side of the head. The cheek is scaly, there 

 being four series of small scales between the procorbital and the in- 

 terior praBopercular ridge. The prteoperculum has the limbs of equal 

 length, and meeting at a right angle, which, however, is rounded. 

 The other opercles are smooth and scaleless ; the operculum has the 

 posterior margin rounded ; the sub- and interoperculum are rounded, 

 and of nearly equal length. 



The dorsal spines are stout, but rather short, the length of the 

 longest being 3| in that of the head ; they are connected by a mem- 

 brane, and can be received in a sheath on the back. The distances 

 of the occiput fi'om the first dorsal spine and from the extremity of 

 the snout are equal. The soft dorsal begins with a spine, a little 

 before the middle of the distance between the occi])nt and the. root 

 of the caudal ; it is ratlun- low, and can be recei^•ed in a scalv shcalli ; 



