THE SLENDER GOBY. 245 



This fish, although closely allied to the other species of 

 the same genus, is undoubtedly quite distinct from them ; 

 the black spot on the first dorsal fin being far more constant 

 and conspicuous than any character which distinguishes 

 the rest of the British gobies. The only species it can well 

 be mistaken for is the G. rrmiutus ; but differs from it in 

 having a black spot between the fifth and sixth ray of the 

 first dorsal fin ; the second dorsal with eleven rays, and the 

 tail fin even at the extremity. Whereas the G. minutus has 

 no black spot between the fifth and sixth ray of the first 

 dorsal fin ; the rays of the second dorsal ten in number, and 

 the tail fin rounded at the end. 



GoBius GRACILIS. — The Slendeu Gobv. Jch. 



Specific Characters. — Dorsal fins remote ; anterior rays of the second 

 dorsal fin shorter than the succeeding ones ; first dorsal fin with six 

 rays, (See Plate XXIX.) 



Description. — From a specimen two and a quarter inches in length. 

 Dorsal line nearl}' straight ; profile falling gradually from the forehead ; 

 body rather elongated, rounded, compressed at the base of the tail ; 

 flattened on the nape ; operculum and preoperculum rounded ; cheeks 

 tumid ; under jaw the longest. Colour of the back and sides reddish- 

 brown ; freckled and streaked with a dark brown ; dorsal and caudal 

 fins barred with the same ; lateral line crossed with seven or eight 

 dark spots, occasionally the middle one extending nearly the depth 

 of the side ; ventral and anal fins dusky, sometimes nearly black. 

 Eyes approximating, situated high on the head, in a line over the 

 angle of the jaw ; first dorsal fin commencing in a line over the up- 

 per third of the pectorals, and ending over the end of the pectoral 

 rays ; all the rays spiny and flexible ; the second, third, and fourth, 

 of equal length. Second dorsal fin taking its origin in a line over the 

 vent and terminating over the last ray of the anal ; the anterior rays 

 shorter than the terminating ones, all branched except the first ; anal 

 fin corresponding to the second dorsal, but commencing a little fur- 

 ther back ; in front of the first ray a small adipose tubercle ; ventrals 

 united so as to form but one fin, placed under the thorax, a little be- 

 hind the base of the pectorals, the middle rays the longest, reaching 

 to the vent ; pectorals on being reflected reach back as far as the 

 middle of the orbit ; the central rays the longe.><t ; tail slightly rounded 



