272 FISHES OF THE FIRTH OF FORTH. 



Cobitis barbatula is very much allied to Betta trenia^ dif- 

 fering from it in having no spines in front of the nose ; 

 whereas B. tcBmah&s a large spine just behind each nos- 

 tril. 



In September last, I rather think that a specimen of 

 Betia tcenia came under my observation in the river Teith, 

 as far as I was able to judge through the dense medium in 

 which it was placed, but failed in obtaining it, in conse- 

 quence of the wind being high, and the water discoloured. 



Family II. ESOCID^E.— Dorsal fin one ; mouth large, 

 with sharp teeth ; intestinal canal short, destitute of caeca; 

 body shaped like the Pike ; nearly all possess a swimming 

 bladder. 



Genus ESOX. — Snout rounded, broad, and depressed ; 

 teeth in both jaws, as well as on the vomer, palatines, 

 tongue and pharyngeans. 



Esox lucius.* — The Pike. 



Specific Characters. — Eye placed half-way between the tip of the 

 snout and the posterior margin of the operculum. 



Description. — From a specimen two feet in length. Body rather 

 elongated ; greatest depth less than the length of the head ; head 

 one-fourth of the whole length, caudal fin included. Colour liable 

 to much variation. " During the earliest stage of its life it is of a 

 greenish hue ; in the second year it becomes grey with pale spots, 

 the latter ultimately acquiring a yellowish colour. Instances have 

 occurred of its being perfectly white." Dorsal fin placed near the 

 tail, the first ray commencing a little in advance of the vent, the last 

 ray in a line over the eleventh ray of the anal ; the middle rays the 

 longest, as long as the base of the fin ; anal fin arising in a vertical 

 line under the seventh ray of the dorsal ; the middle rays the long- 

 est, more than equalling the base of the fin ; caudal fin forked, the 



* Esox lucius, Linn., Cuv., Yar., Jen.,Penn., Don. Pike, Jack, Pickerell, 

 Luce, Gedd. 



