FAMILY ECHENEID^ — ECUENEIS. 307 



FAMILY ECHENEID.E. 



A flattened disk on the upper part of the head, composed of numerous transverse cartilagi- 

 nous movable plates, hy means of which the animal is enabled to attach itself to other 

 bodies. Eyes one on each side of the head. 



Obs. The position of tlii.s family here, is very doubtful. By some ichthyoloi^ists it lias been 

 arranged among the Spine-rayed fishes. Tiieru are but few species, and those chiclly of the 

 tropical seas. 



GENUS ECHENEIS. Linneus. 



Body elongated, covered leith small scales. A single dorsal, placed opposite to the anal. 

 Mouth wide, luith numerous small pectiniform teeth on the jaws. Teeth on the vomer. 

 Branchial rays eight. No air-bladder. Contains feiv species. 



THE WHITE-TAILED REJMORA. 



ECIIENEIS ALEICAUDA. 



PLATE LIV. FIG. 177. — (STATE COLLECTION.) 



The TMtite-taited Rcmora, Echcncis albicauda. Mitchill, Am. Month. Magazine, Vol. 2, p. 21L 

 The Indian Rtniora, E. naucratcs. Stoker, Massachusetts Report, p. 153. 



Characteristics. All the fins margined with white. A dusky longitudinal band along the body. 

 Length twelve to twenty inches. 



Description. Body cylindrical, elongated. Skin granular, and covered with a viscid mucus. 

 Head nearly one-si.tth of the total length ; flat above, with a broad disk extending from the 

 tip of the upper jaw, and beyond the margin of the opercles ; it is surrounded by an elevated 

 border, and is divided throughout its length by a fleshy partition, on each side of which are 

 from twenty-one to twenty-three pair of transverse plates. In four specimens which I exa- 

 mined, the plates varied in number as just noted. The lower jaw broad and rounded, pro- 

 jecting 0' 5 beyond the upper jaw, with numerous recurved card-like teeth. Two scries ot 

 teeth on the upper jaw, and likewise on the vomer and pharyngeals. Opercles smooth, 

 rounded. Eyes large. 



The dorsal fin arises just in front of a line vertical to the vent ; it is long and low, elevated 

 in front, and gradually diminishing behind. The pectorals broad, arising at a point near the 

 dorsal outline of the body, and above the branchial aperture. Ventrals below the pectorals, 

 and united by a delicate membrane. Anal corres|)onding in j)Osition and shape with the dorsal, 

 and beneath that fin. Caudal even at the extrenuty, rounded at the tips ; its rays arc soft and 

 branclied, and surround the extremity of the elongated tail. 



