404 FISHES OF THE FIRTH OF FORTH. 



form to pentagonal, covered with a number of large osseous plates 

 arranged in five longitudinal rows ; the first row commences at the 

 nape, and runs down the back ; the central plates the largest and 

 more elevated than the rest ; the second row arises over the pos- 

 terior margin of the operculum, and runs down the side as far as the 

 end of the tail ; the third row runs from the pectoral down the side 

 of the abdomen ; rows similar to the two last are also observed on 

 the opposite side of the trunk ; each dorsal plate has a broad base, 

 with a sharp elevated keel, terminating in a point directed backwards ; 

 the sixth, seventh, and eighth plate, more raised than those preced- 

 ing ; the base of each is rough with granulations ; the keel smooth, 

 and plain. Colour of the back dusky grey ; belly dirty white ; fins 

 dusky ; keel's of the scales white. Skin rough, with minute plates 

 and points of various shapes, scattered irregularly over the surface ; 

 head sloping in front, covered with rough broad osseous plates ; 

 snout pointed, somewhat of a conical form ; four barbules on the 

 under surface, arranged in a cross direction, placed about half-way 

 between the point of the snout and the anterior margin of the mouth ; 

 mouth situated beneath, about in a line with the eye, of an oval 

 form, without teeth, bordered by cartilage, capable of being greatly 

 protruded. Eyes small ; operculum large, flat, and osseous, marked 

 with a number of granulated striae, radiating from a centre. Dorsal 

 fin placed very remote from the head ; caudal bilobed, the upper 

 lobe much the largest ; anal placed under the posterior half of the 

 dorsal ; ventrals a little in advance of the dorsal ; pectorals situated 

 low down, in a line with the posterior margins of the gill-covers. 

 Number of fin rays — 

 D. 33; A. 23; C. 127 ; V. 23 ; P. 28. 



The Sturgeon inhabits both fresh and salt water, and is 

 a common fish in most of the northern parts of Europe. 

 In some of the American rivers they are found in such vast 

 abundance during the months of May, June, and July, 

 that as many as six hundred are said to have been taken 

 in two days. On the British shores they are by no means 

 common ; seldom more than one individual is taken in the 

 same locality during the season, and then almost invariably 

 in estuaries, or at the mouths of large rivers. They are 

 mostly taken in salmon-nets, but no instance has been re- 

 corded of their being found on lines, or of their taking 



