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Show 6 MR. G. A. BOULENGER ON THE [Jan. 15, premaxillaries and maxillaries. Supraoccipital in contact with the frontals, widely separating the small parietals. Operculum and suboperculum well developed; preoperculum small; interoperculum enormous, covering the gular region and overlapping its fellow; symplectic absent: only three slender branchiostegal rays; no pharyngeal teeth. Ribs stout, sessile, nearly completely encircling the body; slender epineurals ; no epipleurals ; caudal region very short. No postclavicle. Pectoral fins inserted low down, folding like the ventrals ; latter with 6 rays. PHRACTOL^EMUS, gen.n. Body elongate, subcylindrical, covered with large striated scales; lateral line complete, formed of a series of straight tubes extending along the entire length of the exposed part of the scales. Head small, strongly ossified, covered with thiu skin; mouth small, proboscidiform, capable of being thrust forward, when at rest folded over and received into a depression on the upper surface of the head; a single narial orifice, preceded by a barbel; eyes small, lateral. Gill-openings narrow, restricted to the sides; gular region protected by the interopercles, that on one side (usually the right) overlapping that on the other side. Four gills: no pseudobranchise. Pectoral fins small, with 18 rays; ventrals far back, with 6 rays; dorsal short, with 6 rays, opposite to the space between the ventrals and the anal; latter short, with 6 rays ; caudal fan-shaped, with 18 to 20 rays ; all the fin-rays articulated. Air-bladder very large, extending as far back as the anal fin. Stomach with 3 pyloric appendages ; intestine extremely long and much convoluted. 5. PHRACTOL^EMUS ANSORGII, sp. n. (Plate II.) Depth of body 5 to 6 times in total length, length of head 6| to 7 | times. Head depressed, with very broad, slightly convex interorbital region ; diameter of eye 44 to 5 | times in length of head, 3 to 3 | times in interorbital width ; barbel nearly j length of head. Dorsal with the two anterior rays simple, the other four bifid; the first ray equally distant from the head and from the root of the caudal; second ray longest, 1| length of head. Anal similar to dorsal, but rays shorter, the second or longest only | length of head. Pectoral rounded, a little shorter than head, as long as ventral, which is pointed and equally distant from head and from anal. Caudal rounded. Caudal peduncle compressed, nearly as long as deep, as long as head. Scales large, longitudinally striated, 35 to 37 in a longitudinal series, 'fL in a transverse series. On the caudal region the scales of the lateral line and those of the series above it may bear a central sclerous tubercle (probably a seasonal character). Uniform olive-grey. The vertebra?, in a male specimen of which a skeleton has been prepared, number 34, 26 precaudal and 8 caudal, the last bearing 6 bypurals lo support the homocercal fin ; the ribs are subequal, |