The Chub is a well-known fish that is common in the Thames, and many other rivers of England: it is said to be plentiful in the Wye, and other rivers of Wale, it is also recorded as an inhabitant of the Annan, and other rivers in the south of Scotland.
In its nature the Chub is timid, frequenting deep holes in the more quiet parts of the sides of the stream, and sheltering itself generally under or near any bush or tree that will screen it from view. It feeds on worms and on insects in their various stages ; and is mostly caught by anglers with a fly or other bait at the surface of the water, by a mode of fishing called dibbing. The Thames anglers for Chub "cause themselves to be landed on an ait in the river, the banks of which, under the shelter of the willows, with a long rod, a short line, and a lively cockchafer, they often have good sport." The insect used as bait, whatever it happens to be, whether large moth or cockchafer, hangs pendent from the point of the rod, just touching the water ; and by repeatedly but gently tapping the butt-end of the rod, the bait is moved in a manner exactly resembling the struggles of a living insect that had by accident fallen into the water.
Mr. Jesse says of the Chub, detained with other fish where their actions could be noticed, that they were always restless and shy, but could never resist a cockchafer when thrown to them.
The Chub spawns about the end of April or the beginning of May but does not acquire a large size ; five pounds' weight is the most that I can find recorded. It is considered a coarse fish, and broiling with the scales on is one of the best modes of preparing it for table.
The length of the head compared to the length of the head and body to the end of the fleshy portion of the tail is as one to four ; the depth of the body rather greater than the length of the head ; the mouth large ; the head wide or chubby ; the nostrils in a circular depression, one-third nearer the eye than the end of the nose ; the diameter of the eye equal to one-fifth of the length of the whole head : the scales on the body large ; the number forming the lateral line forty-four, with an oblique line of six scales above it to the base of the dorsal fin, and of three scales below it to the origin of the ventral fin ; the lateral line descending by a gentle curve till even with the end of the pectoral fin-rays then straight to its end.
The dorsal fin commences half-way between the point of the nose and the end of the fleshy portion of the tail ; the first ray short, the second the longest, both simple ; the others branched, diminishing in length gradually to the last, which is the shortest ; the seventh ray as long as the base of the dorsal fin : the pectoral fin rather small ; the ventral fin arising on the same vertical plane as the dorsal; the anal fin large, commencing in a line with the end of the dorsal fin when its rays are pressed: the tail large and forked.The colour of the top of the head blackish brown, with a streak of the same dark colour passing down behind the free edge of each operculum as far as the origin of the pectoral fin : the whole of the upper part of the back bluish black, the edge of each scale the darkest part ; the sides bluish white, passing into silvery white on the belly: the dorsal and caudal fins dusky; the pectoral fins reddish brown ; the ventral and anal fins reddish white ; the irides golden yellow, the upper part dusky ; cheeks and gill-covers rich golden yellow.
The fish described was a male of thirteen inches in length, and the milt appeared on pressure.