180 CLASSIFICATION OF FISHES. 



adhere at ditferent places, by blood-vessels passing from 

 one to another : the number of these partitions in a 

 column one inch in length, appeared to be 1 50 ; this 

 proportion was so regular in several individuals^ that it 

 seems, as the fish grows, new partitions are added to the 

 extremity of the column from the fascia : the partitions 

 are very vascular. The arteries are branches from the 

 veins of the gills, which convey the blood which has 

 received the influence of respiration : they pass, along 

 with the nerv'es, to the electric ortran. and enter with 

 them ; they then ramify in every direction. The veins 

 of the electric organ pass out close to the nerves, and 

 run between the gills to the heart : the nerves inserted 

 into each electric organ^ arise from three very large 

 trunks placed on the lateral and posterior part of the 

 brain, and then ramify in every direction between the 

 columns. 



('160.') The number and ma2;nitude of the nerves, 

 bestowed U'^on these organs, in proportion to their size, 

 must, on reflection appear as extraordinary as the pheno- 

 mena they afford. Nerves are given to parts either for 

 sensation or action : if we except the more important 

 senses of hearing, seeing, tasting, and smelling, which 

 do not belong to the electric organs^ there is no part, 

 even of the mosr perfect animals, which, in proportion 

 to its size, is so liberally supplied with nerves ; nor do 

 the nerves seem necessary for any sensation which can 

 be supposed to belong to the electric organs ; and with 

 respect to action, there is no part of any animal, how- 

 ever strong and constant its natural action may be, 

 which has so gi-eat a proportion of nerves. If it be, 

 then, probable that those nerves are not necessary for the 

 purposes of sensation or action, may we not conclude 

 that they are subservient to the formation, collection, or 

 raana gement of the electric fluid ? especially as it ap- 

 pears evident, from Walsh's expermients. that the will 

 of the animal does absolutely control the electric powers 

 of its body, which must depend on the energy of the 

 nerves. 



