Jordan and Evermanii. — Fishes of North America. 2273 



837. RHOMBOCHIRUS, Gill. 

 Bhombochirufi, Gill, Proc. Ac. Nat. Sci. Phila. 1863, 88 (osteochir). 



This genns agrees with Femora in every respect excepting the structnre 

 of the pectoral tins. These are short and hroacl, rhombic in outline, the 

 rays all flat, broad and stiff", being partially ossified, although showing 

 the usual articulation ; upper rays of pectoral broader than the others. 

 One species known, {fjojti /Joi,rhomh; jez'p, hand.) 



2609. UnOMBOCHIKUS OSTEOCHIR (Ciivior). 



Head 4f in length ; disk 2J ; width between pectorals 5. D. X VIII-21 

 to 23; A. 20 or 21; P. 20. Mouth very small, maxillary not nearly reach- 

 ing to the line of the orbit ; outer series of teeth longer than the others. 

 Disk very large, broader and rougher than in liemora remora, extending 

 forward beyond the tip of the snout. Caudal fin emarginate, with rounded 

 angles. Light brown ; underside of head, ventral line, part of ventrals 

 and a sjoot on pectorals pale. West Indies north to Cape Cod; parasitic 

 on species of Tetrapttirus ; rather rare, {odreov, bone; x^iP> hand.) 



Eeheneis osteochir, Cdvier, Regne Animal, Ed. 2, vol. ii, 348, 1829, no locality given ; 



GiJNTHEE, Cat., n, 381,1860; Jordan & Gilbert, Synopsis, 418, 1883. 

 Eeheneis tetmpturorum, Poey, Memorias, ii, 256, 1858, Cuba. (Coll. Poey.) 



Group TRACHmOIDEA. 

 (The Trachinoid Fishes.) 



A large group of transitional forms, some of them of doubtful relation- 

 ships, showing affinities with the rercoidea on the one hand and with the 

 Batrachoidida: and Blennoidea on the other. In general, the spinous dorsal is 

 short or weak, the soft dorsal long and similar to the anal, and the squama- 

 tiou is less complete and less ctenoid than in the Percoidea. The skull is, in 

 general, depressed, with the supraocular crest low, and the suborbital stay 

 is wanting, although in some genera the suborbital bones are enlarged. 

 The bones of the skull are not strongly armed, and the ventral fins are 

 often inserted well forward, and they are sometimes reduced in size. 

 Tlie group is divided by Dr. C4ill into Fercophidoidea, Trachinoidea, and 

 Uranoscopoidea. The two latter groujis are natural and related, but, as 

 Dr. Gill observes, "the Fercophidoidea are undoubtedly a heterogeneous 

 group and need a thorough revision." The relations oi Bathy master, Tricho- 

 don, and Latilus especially are uncertain. Several of the leading families 

 of this group are confined to the South Temperate Zone, and none of the 

 Trachinidw occurs within our limits. 



a. Mouth horizontal or moderately oblique, the lips notfrin<;ed; eyes lateral; ventral 

 rays I, 5, their insertion more or less before the pectorals ; suborbitals moderate ; 

 gills 4, a slit behind the fourth. 

 h. Snout subcouic, not prolonged and spatulate; ventrals not widely separated, 

 c. Body covered with scales; dorsal spines flexihle. 



d. Lateral line complete ; caudal fin forked ; vertebras 24 to 27. 



Malacanthidje, cxo. 



