70. ECHENEIDID^ RHOMBOCHIRUS. 417 



Maxillary barely reacliiiig vertical from nostril. Head 5 J in length ; 

 disk 3|; width between pectorals about 7^. D. XXI-XXV— 32-41 ; 

 A. 34 (32-38). In all warm seas, north to Cape Cod and San Francisco. 



(Liun. Syst. Nat.; Giiuther, ii, ;?84 : Lepteehencis naucrates Gill, Proc. Acad. Nat. 

 Sci. Pliila. 1864, GO. EcluufiH naiicrateoides Ziiieuw, Nova. Acta. Acad. Sci. Imp. Petro- 

 pol. iv, 279, Leptechentis naucralcotdcs Gill, Proc. Acad. Nat. Sci. Phila. 1864, 61, Ech- 

 encis albicauda Mitch. Amer. Monthly Mag. ii, 244. Echcneis lineata Holbr. Ichth S. C. 

 1860, 102, and Echeneis holbrooki, Giiuther, ii, 382, are names applied to specimens with 

 the disk comparatively long, but with only 21 lamina3.) 



aa. Body rather robust ; vertebrcC 12 -j- 15. (Tiemora* Gill.) 

 h. Dorsal rays about XVIII-23. 



658. E. rcniora L. — Bemora. 



Uniform dark brown. Body and tail comparatively robust, the latter 

 compressed. Pectoral fins rounded, short, and broad, their rays soft 

 and flexible; ventral fins adnate to the abdomen for more than half 

 the length of their inner edge. Tip of lower jaw not produced into a 

 flai). YertebriB 12 + 15. Head broad, depressed Disk longer than 

 the dorsal or anal fin. Maxillary scarcely reaching front of orbit. 

 Caudal lunate; vertical fins rather high; pectoral f length of head. 

 Head 4; disk 2f ; width between pectorals S^. D. XVlII— 23; A. 25. 

 Warm seas, north to New York and San Francisco, usually found at- 

 tached to large sharks. 



{Eclieneis remora L. Syst. Nat. : Ecliene'is jacoboea Lowe, Proc. Zool. Soc. London, 1839, 

 89: Echeneis remora Giinther, ii, 378: Beinora jacohoca Gill, Proc. Acad. Nat. Sci, Phila. 

 1862, 239.) 



aa. Dorsal rays about XVI-30. (Uemoropsis Gill.) ' 



659. E. bracliyptcra Lowe. 



Light brown, darker below; fins paler; body robust, the greatest 

 depth nearly twice the length of the short pectoral fins; disk shorter 

 than base of dorsal, rather broad; upper jaw angular. Caudal nearly 

 truncate. Head nearly 4; width between pectorals C^. D. XVI — 30; 

 A. 2C. Warm seas, north to Massachusetts. 



(Echeneis hrachijptera Lowe, Proc. Zool. Soc. Lond. 1839, 89: Echeneis quatuordecetnlam- 

 iiiatus StoriT, Hist. Fish. Mass. 400: Echeneis hrachijptera Giiuther, ii, 378: Eemoropais 

 bruchypterus Gill, Proc. Acad. Nat. Sci. Phila. 1864, 00.) 



207.-RBIOMBOCH1RUS Gill. 



(Gill, Proc. Acad. Nat. Sci. Phila. 1863, 88: type Echeneis osteochir Cnv.) 



This genus agrees with Remora in every respect excepting the struc- 

 ture of the pectoral fins. These are short and broad, rhombic in outline, 



*Gill. Proc. Acad. Nat. Sci. Phila. 1862, 239: type Echeneis remora L. {Remora, an 

 ancient name, "holding back.") 



Bull. Nat. Mus. No. IG 27 



