234 ZOOLOGT. 



lengtli about nine times, or a little over. The greatest thickness stands, in regard to the 

 length, as one to six or two to thirteen. The dorsal outline is more convex than in Perdclithys 

 cMlensis, and mayhap also the belly, which contributes not in a small degree to give to this fish 

 that more contracted appearance already alluded to above. The head is sub-conical, and par- 

 ticipates in the short aspect of the body. Its upjier surface continues, towards the tip of the 

 snout, the declivity of the nape with scarcely any inflexion upon either the occiput or the ocular 

 region. The snout itself is blunt and rounded, slightly overlapping the lower jaw when the 

 mouth is shut. The upper arcade of the mouth is but little protractile, and, when in the latter 

 state, causes the maxillaries to move more downwards than forwards. There are minute card- 

 like teeth on both the upper and lower jaws, and closely set together. Velvet-like teeth may be 

 observed on the front of the vomer, disposed upon a small triangle. , The palatines exhibit a 

 few rudimentary teeth upon their anterior extremity in contact with the vomer. The palate is 

 otherwise smooth. The pharyngobranchials are large, elongated, and convex, and closely set 

 with prickly teeth ; the inferior pharyngobranchials are smaller, subtriangular, and slightly 

 concave, likewise set with similar teeth. The tongue is smooth, flattened, tapering anteriorly. 

 The mouth is moderate, the posterior extremity of the upper maxillary reaching a vertical 

 which would pass in advance of the orbit only. The eye is subcircular, and well developed; its 

 horizontal diameter being contained a little over four times in the length of the side of the head. 

 The anterior suborbital is broadly developed, overlapping considerably the wpper jaw. Its ex- 

 ternal edge is minutely crenated. The serratures of the ascending branch of the preopercle 

 are rather more developed than in P. cMlensis, though the spines on the lower branch are pro- 

 portionally of the same size. The opercular apparatus, as a whole, is constructed upon the 

 same pattern in both P. cMlensis and P. melanops. The inferior margin of the sub and inter- 

 opercle are similarly crenated, and a flattened spine may be seen across the middle of the oper- 

 cle, extending its point beyond the edge of that bone, mayhap a little more acute and more 

 conspicuous in P. mdanops than in P. cMlensis. The suprascapular is likewise crenated, and 

 the coracoid expansion above the base of pectoral fins, wanting, however, the minute spines ob- 

 served in P. cMlensis. The branchiostegals, six in number, are flattened and curved. The 

 gill openings communicate together under the throat, being shaped exactly as in P. cMlensis. 

 The distance between the tip of the snout and the origin of the first dorsal is a little greater 

 than the base of both dorsals. The general structure of these fins is the same as in P. cMlensis, 

 with the exception that the third spine is the longest instead of the fourth. The membrane 

 between the spines is deeply emarginated. Eight rays constitute, properly speaking, the ante- 

 rior fin ; two are intermediate between the eighth and the eleventh, which is situated at the 

 anterior margin of the second or posterior fin. The central rays of the latter bifurcate also 

 twice, and their tips extend evenly with those of the anal. The anal is preceded by three spines, 

 and its soft rays are bifurcated in the same manner as those of the second dorsal. The poste- 

 rior margin of the caudal is subemarginated with its central rays thrice bifurcated ; it consti- 

 tutes a little less than the sixth of the entire length of the fish. The origin of the ventrals cor- 

 responds to a vertical line which would pass immediately behind the base of the pectorals. They 

 are broad and rounded exteriorly ; their central rays being bifurcated three times, with the an- 

 terior spine longer than in P. cMlensis. The pectorals are rather short, and broad when ex- 

 panded; their tijw do not extend as far backwards as those of the ventrals; the rays are slender 

 and bifurcate twice. 



Br. VI; D XI. 10; A III. 9; C 6. I. 8. 7. I. 5; VI. 5; P 15. 



The scales are of medium development, and very minutely, if at all, crenated upon their pos- 

 terior margin, which is irregular])'- rounded. Their anterior margin is straight, and the ujiper 

 and lower edges linear and parallel, the scales being much longer than broad. There are ten 

 distinct rows between the lateral line and the anterior margin of the first dorsal, besides some 

 few irregularly dis]iosed near the base of that fin ; twenty row8 and more may be counted 



