74 GENERA AND SPECIES. 



Agonus. Plate viii. DACTYLOPTERID&. 



58. cataphractus, POGGE. Body octagonal ; barbules under throat, white. 

 The Pogge, or Armed Bullhead, bears a distant resemblance to 

 the sea-horse. It has two dorsal fins, the first with 5 spines and the 

 second with 5 or 6 rays ; in the anal fin there are 6 rays, in the 

 caudal 12 ; the pectorals have 16 rays, and the ventrals a spine and 

 2 rays. The dorsals are almost semi-circular, and the pectoral is 

 very broad, and extends beyond the middle of the first dorsal. The 

 body is divided by ridges of bony plates into 8 sides, and between 

 the two side ridges runs the lateral line of 32 scales, which are without 

 spines. The mouth nearly extends to the front edge of the eye, and 

 there are many barbules. There are no teeth except in the jaws. 

 In colour the Pogge is pinkish or yellowish grey, with broad vertical 

 bands and many spots. The pectorals are distinctly banded, the 

 other fins not so much so: This is a bottom-feeding species, haunt- 

 ing the mouths of rivers and similar places. It rarely exceeds 

 6 inches in length. 



Alburnus. Plate xxiii. CYPRINID^. 



182. lucidus, BLEAK. Tail with lower lobe longer than upper ; anal 

 fin broad and cut square. 



The Bleak has a single dorsal fin with 2 or 3 spines and 7 or 8 

 rays ; the anal fin has 2 or 3 spines and from 16 to 20 rays, and the 

 caudal has 19 rays ; in the pectorals there are 16 or 17 rays, and in 

 the ventrals there are 9 or 10. The dorsal is midway between the 

 eye and the base of the caudal ; the anal is the broadest fin and is 

 curiously square at the corners ; the pectorals are pointed. The 

 lateral line curves downwards from the nape and rises to meet the 

 caudal below the middle. It has from 47 to 57 scales, and there are 

 3^ rows of scales between it and the base of the ventral fin. The 

 mouth does not reach to the fore edge of the eye, and the lower 

 jaw is hooked and projecting. In colour the Bleak is greenish above 

 and silvery below, with a blue stripe along the side. It attains a 

 length of 8 inches, but is generally caught smaller, and is not a 

 favourite with anglers owing to its frequently taking the bait intended 

 for other fish. It swims near the surface in rivers and running 

 waters, always in shoals, which are generally more numerous where 

 drains enter the stream, and it is particularly apt at springing out ot 

 the water after flying insects, and making more fuss than its size 

 would lead one to suspect. 



Alopecias. Plate xxix. LAMNIDJE. 



227. vulpes, THRASHER. Upper lobe of tail as long as body. 



The Thrasher, otherwise the Fox-shark, is unmistakable, owing 

 to its peculiar tail. It has a stout, sturdy body, with a very large 

 pectoral fin, a forked first dorsal about the same size as the pectorals, 

 and very small second dorsal and anal. The mouth is in the shape 

 of a crescent, the teeth are small, flat, and triangular, with smooth 

 edges. The body is darker above than below, but the colour varies 

 very much, though it is generally some shade of grey. This energetic 

 shark is by no means rare in British waters, and has been caught 

 over 15 feet long. 



