in the Nahiral Hlslory of the common EeL 275 



if a solitary qnany-pit, which had been excluded for a 

 dozen years even from day-light, were to discover to us an 

 occurrence which is never displayed in our multitudinous 

 open pools, where the same animals are equally restricted 

 from escape. 



In contradistinction to the vast emigration of old eels 

 down the streams in autumn, an immensely greater mi- 

 gration of young ones comrntnjces up the streams in spring 

 and sunnner. Their size varies between the smallest and 

 the largest darning needle. They are called elvers, and 

 abound in some of our large rivers to an inconceivable ex- 

 tent. In some places biishels of them are taken with bas- 

 kets fixed on to the ends of poles, and drawn swiftly through 

 the water. Their progress is always along the banks, and 

 numerous portions pass up into all the lateral streams. The 

 smallest brook and the minutest rill that can run receive 

 their proportion; and it is solely in this way that every piece 

 of water, however or wherever it may be situated, receives 

 the eels that are found in it. The smallest possible trick- 

 ling of water from any pool to the nearest brook, is suffi- 

 cient to enable these little indefatigable animals to wind 

 (heir way up to the source. The instinct, indeed, which 

 impels tiiem upwards against all moving water seems 

 incessant and irresistible; it surmounts every difficulty, 

 and perseveres successfully against every obstacle how- 

 ever imperious. During the low state of streams in the 

 early part of summer, "they may be found at weirs, mill- 

 dams, cascades, and other elevations across the streams, 

 Qsccnding by the margin of the water perpendicular walls 

 many feet in height, where the least crevice in the stone, 

 or patch of moss'J affords them a hold ; and they will even 

 find their way over vertical dry boards, by adroitly em- 

 ploying their glutinous exterior. 1 have taken them in 

 handfuls from patches of wcbmoss against erect walls, com- 

 pktcly out of the water, and where the height and distance 

 to be surmounted would require the persevering efforts of 

 many days. In very snjall pellucid brooks, adjacent to 

 rivers where they abound, they may be seen wriggling up 

 the little streams in endless succession for weeks together. 

 Great numbers doubtless perish by ascending the temporary 

 rills produced from rain, and by reaching spring-heads, 

 and situations where the water is insufficient for their 

 growth and support; but in this, as in every other instance, 

 provident nature has guarded against all such casual ex- 

 penditure by the superabundance of the production. 



S 2 In 



