FISH. 97 



fins, and consequently a larger interval between the anal and the caudal ; also, in 

 the number and arrangement of the dotted lines on the cheeks. The colours are 

 likewise different ; and, in the living fish, in which they were not noticed, probably 

 the dark longitudinal lines, alluded to in the description above, are much more 

 conspicuous than they are at present. 



This species was taken by Mr. Darwin off Chatham Island, in the Galapagos 

 Archipelago. 



2. Gobius ophicephalus. Jen. 



Plate XIX. Fig. 3 

 G . pallenti-plumbeus,fiisco-reticulatus : corpore elongato, gracili, undique alepidoto : 

 capita lato, depresso, gents tumidis ; his et rostro punctis valde salientibus, creberri- 

 mis, lineis undantibus dispositis: maxillis cequalibus : dentibus velutinis ; externis, 

 prcesertim lateralibus, fortioribus, aculeiformibus ; caninis nullis : oculis parvis, 

 prominulis, intervallo plus quam diametrum aquante : pinnis dorsalibus subcontiguis, 

 altitudine subcequalibus ; pectoralibus radiis omnibus membrand inclusis ; caudali 

 rotundatd, radiis clausis, subacuta. 



D. 8 — 1/16 ; A. 1/13 ; C. 17, &c. ; P. 21 ; V. 1/5. 

 Long, una 2. lin. 11. 



Form. — Body considerably elongated, and compressed posteriorly : the greatest depth beneath the 

 first dorsal, equalling rather less than one-eighth of the entire length : thickness at that point 

 rather less than the depth. Head broader than the body, very much flattened in the crown 

 behind the eyes, with the cheeks tumid, and, on the whole, snake-like in appearance : its 

 length one-fifth of the entire length ; its breadth two-thirds of its own length. Eyes small, but 

 rather prominent, high in the cheeks, with a diameter scarcely exceeding a line in length, or 

 about one-sixth that of the head ; the space between a little hollowed out, and nearly a 

 diameter and a half across. Snout short and obtuse: jaws equal; the gape not quite reaching 

 to beneath the middle of the orbit. The teeth form a broad velutine band in each jaw, with 

 those in the outer row strong and slightly hooked : of these last there are about twenty in the 

 upper, the lateral ones being stronger than those in front ; in the lower they are not so 

 numerous, and more irregular : none that can be strictly called canines : likewise no vomerine 

 or palatine teeth. 



Pectorals one-sixth of the entire length, oval, with the middle rays longest; all the rays 

 included in the membrane. Ventrals united; about two-thirds the length of the pectorals. 

 First dorsal extending beyond the extremities of the pectorals ; the rays very gradually 

 decreasing in length, the membrane beyond the last also sloping very gradually down till it nearly 

 reaches the second dorsal, which it does not quite touch. Rays of the second dorsal of nearly 

 uniform height, about equalling the longest of those in the first, also equalling the depth of the 

 body beneath. The last ray in both these fins is double, as in the last species. The anal com- 

 mences beneath the fourth ray of the second dorsal, and terminates a little sooner than that fin. 

 The caudal, when the rays are spread, appears rounded ; but when closed, somewhat pointed : 



o 



