40 THE VOYAGE OF H.M.S. CHALLENGER. 



than the lengtli__of the liead, and contained thrice and three-sevenths in the total length 

 (without caudal) ; snout rather short, as long as the eye, the diameter of which is two- 

 sevenths of the length of the head. The maxillary reaches the front margin of the 

 eye ; lioth jaws with four canine teeth in front, the upper with a posterior one ; oper- 

 culum dilated into a large flap ; three series of scales on the cheek ; sub- and inter- 

 operculum scaly ; pra^orbital as high as the orbit. Dorsal spines rather slender. 

 Rose coloured ; a blackish spot below the sixth and seventh dorsal spines on the lateral 

 line ; another above the end of the lateral line above the caudal fin. Length of specimen, 

 4 inches. Arafura Sea. 



Chosrops cyanodon, Rich., Somerset. 



Chceroj^s ommopterus, Rich. Station 186 (trawl). 



Ophidmm muroenolepis, n. sp. (PI. XX. fig. A). 



The length of the head equals its distance from the vent, which is somewhat nearer to 

 the end of the snout than to that of the tail. (In Ophidium hroussoneti the distance of 

 the vent from the end of the tail is nearly twice that from the end of the snout. ) The 

 scales are extremely small, not imbricate, elongate, and obliquely arranged as in an eel. 

 The outer pair of barbels is considerably longer than the inner, and much shorter than 

 the head. The lower branch of the outer branchial arch with four gill-rakers, which are 

 very short, scarcely one-third of the diameter of the eye. No hook-like prominence at 

 the ethmoid. Head entirely naked. Dorsal fin with a blackish edge. Ki Islands. 

 Length of specimen, 7 inches. Station 192; 129 fathoms. 



Pseiidorhombus russelli, Gray, Arafura Sea ; 35 to 49 fathoms. 



Rhomboidichthys angustifrons, n. sp. (PI. XXI. fig. B). 



D. 83, A. 62, L. lat. 80. The height of the body is a little more than one-half of the 

 total length with the caudal ; the length of the head one-fourth ; head about as high as 

 long ; anterior profile of the head parabolic, with a small notch in front of the inter- 

 orljital space. Cleft of the mouth narrow, with the lower jaw prominent, and with the 

 maxillary extending to below the front margin of the orbit ; snout a little shorter than 

 the eye, the diameter of wdiieh is two-sevenths of the length of the head. An inconspicu- 

 ous knob superiorly on the maxillary, and on the front margin of the lower orl)it. 

 Length of the maxillary a Httle less than one-third of that of the head. Interorbital 

 space very narrow, deeply concave, smooth. Vent on the left side. Scales of the 

 coloured side ethmoid, of the l^lind side smooth. No spines along the base of the dorsal 

 and anal fins. In the single specimen observed, the anterior dorsal rays are nearly 

 detached and produced. Light brownish with indistinct darker spots, of which a series 



