lOG FISHKS OF THE FiRTH OF FORTH. 



the coast, it is by no means common in the Firth of Fortli. 

 The only places I know of its occurrence are between Bo'- 

 ness and South Queensferry, and in the vicinity of Aber- 

 lady, and then seldom more than five or six are found toge- 

 ther. Further south on the same coast, in the neighbour- 

 hood of Berwick-upon-Tweed, it is more frequently met with, 

 inhabiting brackish water in preference to either fresh or salt 

 water. The young when disturbed are remarkably active, 

 darting about in every direction, and will often, to avoid the 

 pursuer, bury themselves an inch or more under the surface 

 of the mud. They are of little or no use except as manure 

 for the land. They spawn in spring, and feed on insects, 

 worms, and the fry of other fishes. 



Gasterosteus spinui.osus.* — The Fouk-spineb 

 Stickleback 



Specific Characters. — Back armed with four spines. (See Plate 

 XXV.) 



Description. — From a specimen one inch and a half in length. Body 

 of an oval form ; sides compressed ; operculum, preoperculum, and 

 scapular plate rounded at the posterior margin ; under jaw the 

 longest; dorsal and anal fins of the same form, graduallj' decreasing 

 from before backwards ; caudal fin slightly concave ; second and 

 third dorsal spines the longest, the fourth the shortest, not half the 

 length of the first. Lateral line commencing over the base of the 

 scapular plate, following the line of the curve of the back to the base 

 of the tail. First dorsal spine placed over the base of the pectorals ; 

 second over the ascending portion of the pelvic plate ; the third 

 over the end of the ventral spine ; dorsal fin commencing close be- 

 hind the last dorsal spine, and ending over the last ra}' of the anal ; 

 anal fin commencing under the third dorsal ray. Lateral plates 

 about three in number, extending down as far as the end of the pec- 

 toral rays ; from thence to the tail the sides are naked, marked like 

 G. leiurus with linear transverse depressions ; ventral fin composed 

 of a strong serrated spine, attached behind to a small ray, placed at 

 tlie base of the ascending portion of the pelvic plate. Eyes large ; 

 teeth small and fine in both jaws, none on the vomer or palatines ; 



* Gasterosteus spuiitlosiis, Yar., .Ten. 



