FISH. 



141 



ing wide, the membrane free all round, with six rays. Opercle terminating behind in a blunt 

 point : there is also a kind of double spine concealed in the thickness of the branchial mem- 

 brane, in front of the ordinary branchial rays, the extreme end of one portion of which projects 

 a little beyond the margin. 



The dorsal commences a little beyond the middle of the entire length, and leaves a space 

 between it and the caudal ; the rays nearly equal, except the first, which is short. The anal 

 begins under the fourth or fifth dorsal ray, and extends a trifle further than that fin. Caudal 

 slightly rounded. 

 Colour — (In spirits.) Back and sides light brown, reticulated with black : the reticulations have 

 a tendency to form three or four broad fasciae across the back. Under parts yellowish. 



Habitat, Archipelago of Chiloe. 

 This and the following species appear to belong to the genus Gobiesox of 

 Cuvier's " Regne Animal," and are probably new. Two specimens of the one 

 above described were found by Mr. Darwin under stones off the island of Lemuy, 

 in the Archipelago of Chiloe. 



2. Gobiesox po2cilophthalmos. Jen. 



Plate XXVII. Fig. 2. 

 G. fuscescenti-albidus, immaculatus : dentibus anterioribus majoribus, supra et subtus 

 incisivis : operculo postice spina acuta armato ; membrand operculari margine, supra 

 spinam, cirris paucis filamentosis fimbriate- ; membrand branchiali spina nulla : pin- 

 nis dorsali et anali septem-radiatis. 



B. 6; D. 7; A. 7; C. 12; P. 23; 

 Long. unc. 1. lin. 10. 

 Form. — General form the same as that of the last species, including the proportion of head to body. 

 Snout equally rounded. Teeth on the whole similar, but the upper ones in front, as well as 

 the lower, incisor-like. Eyes rather larger, closer together, less than a diameter apart. Differs 

 essentially from the G. marmoratus in the form of the opercular spine, which is much sharper, 

 as well as somewhat longer and slenderer ; also in having no spine concealed in the branchial 

 membrane : the lower part of the opercular membrane, just above the spine, is fringed with a 

 few thread-like filaments. The number of branchial rays is the same. 



The dorsal and anal are both shorter, and appear to have only seven rays each : the anal 

 reaches a little nearer the caudal. The pectorals on the contrary have rather more rays. 

 Colour — (In spirits.) Every where of a uniform very pale brown, or brownish white, without any 

 markings whatever. The eyes were probably very brilliant in the living fish, the irides still 

 showing traces of what seems to have been blue and golden pink. 



Habitat, Galapagos Archipelago. 



A single individual of this species was obtained by Mr. Darwin in tidal pools 

 at Chatham Island, in the Galapagos Archipelago. 



