TION. 



354 THREE SPINED S. BACK. Class IV. 



be the multitudes that have been washed out of 

 the fens by the floods of several years, and col- 

 lected in some deep hole, till overcharged with 

 numbers, they are periodically obliged to at- 

 tempt a change of place. The quantity is so 

 great, that they are used to manure the land, 

 and trials have been made to get oil from them. 

 A notion may be had of this vast shoal, by saying 

 that a man employed by the farmer to take them, 

 has got for a considerable time four shillings a 

 day by selling them at a halfpenny per bushel. 

 Descrip- This species seldom reaches the length of two 

 inches -, the eyes are large; the belly promi- 

 nent ; the body near the tail square ; the sides 

 are covered with large bony plates, placed trans- 

 verselv. On the back are three sharp spines, 

 that can be raised or depressed at pleasure; the 

 dorsal fin is placed near the tail ; the pectoral 

 fins are broad ; the ventral fins consist each of 

 one spine, or rather plate, of unequal lengths, 

 one being large, the other small ; between both 

 is a flat bony plate, reaching almost to the vent ; 

 beneath the vent is a short spine, and then suc- 

 ceeds the anal fin ; the tail consists of twelve 

 rays, and is even at the end. The color of the 

 back and sides is an olive green; the belly 

 white ; but in some the lower jaws and belly 

 are of a bright crimson. 



