OV NATURAL HISTORY. 499 



from twelve to fixteen inches long, and gradually augment, 

 both in number and lize, till about the end of July or begin- 

 ning of Auguft, when they weigh from fix to nine pounds. 

 This is a very rapid growth. But a gentleman of credit at 

 Warrington informed Mr. Pennant of a growth ftill more 

 rapid. A falmon, weighing feven pounds and three quar- 

 ters, was taken on the feventh day of February. It was mar- 

 ked on the back, fin, and tail, with fcifTars, and then turned 

 into the river. It was retaken on the I7th day of the fol- 

 lowing month of March, and then it weighed feventeen 

 pounds and a half. The feafon for filhing falmon in the 

 Tweed begins on the 30th of November, and ends on old 

 Michaelmas day. In that fingle river, it is computed that 

 no lefs than tiOSOOO, at a medium, are annually caught, 

 -which, together with the products of many other rivers on 

 both (ides of Scotland, not only afford a wholefome and pal- 

 atable food to the inhabitants, but form no inconliderable 

 article of commerce. 



Herrings are likewife a<Sluated by the migrating principle. 

 Thefe flflies are chiefly confined to the northern and tenv 

 perate regions of the globe. They frequent the highefl lati- 

 tudes, and are fomctimes found on the northern coafts of 

 France. They appear in vaft flioals on the coad of America, as 

 far fouth as Carolina. In Chefapcak bay there is an annual in- 

 undation of herrings •, and Mr. Catefby informs us, that they 

 cover the fhores in fuch amazing numbers as to becom.e offcn- 

 five to the inhabitants. The great winter rendezvous of the 

 herrings is within, or near the Arctic Circle, where they re- 

 main feveral months, and acquire firength after being weaken- 

 ed by the fatigues of fpawnlng, and of a long migration. In 

 thefe feas, infect food is much more abundant than in warm- 

 er latitudes. They begin their migration fouthward in the 

 fpring, and appear off the Shetland iflands in the months of 

 April and May. Thefe, however, are only the foreruimers 



