170 NEPHTHYACE^. 



agitation continued only a few seconds, when the animal subsided to 

 the bottom, unable to exhibit any further signs of motion than some 

 partial convulsive twitches in different parts of its body, or a quiver- 

 ing here and there in its segments or articulations. The skin of the 

 body was contracted in various places, so as to present a wrinkled or 

 withered appearance. In six minutes from the immersion the animal 

 seemed perfectly dead; the wrinkled appearance of the skin was 

 gone, and not the slightest mark of irritability appeared in any part. 

 The other specimens, eight in all, exhibited the same phsenomena 

 with little variance. None of them showed any appearance of vitality 

 after ten minutes' immersion. Three of them protruded very slowly 

 their remarkable ventricose proboscis (if the latter term can be at all 

 appropriate) during their last expiring moments, and so it remained 

 after death. 



" I allowed the above specimens to remain in water all night ; and 

 on the following morning, on going to put them in spirits in order 

 to preserve them, I was surprised to find them so rotten, that they 

 fell in pieces by their own weight, and were quite useless as speci- 

 mens. They had not, however, acquired any offensive or putrid 

 smell. 



" Some days afterwards I obtained a fresh supply of living speci- 

 mens, some of which were entire ; but a number of them were in 

 fragments, having been cut through by the spade in digging. The 

 latter were quite alive, and seemed to have suffered no more in point 

 of vitality by having been cut, than the common earthworm does 

 under similar circumstances. I had proof, too, that the being cut 

 through does not prove fatal ; for, in one of the entire specimens, 

 about two inches of the tail end was a new production. The animal 

 had, at some prior period, been severed by the bait-digger, and a 

 new portion had been restored. This portion, as is generally the 

 case with reproductions, was smaller in diameter than the rest of the 

 animal. It was also of a paler hue, and the line of demarcation 

 between the old and the new parts was very distinctly marked. 



*' The separate pieces of the cut worms, even those which wanted 

 both head and tail, were affected by the fresh water in the same way 

 as the entire specimens : they were first thrown into violent convul- 

 sions, then became affected with transient spasms, and, in a few 

 minutes, all appearance of vitality was extinguished. 



" The first idea that struck me, as to the possible cause of these 

 phaenomena, was, that perhaps the water, from wanting the density 

 of sea water, was unfit for respiration, and that therefore the animals 

 had died of suffocation. Pennant states that the torpedo dies in 

 fresh water almost as soon as in the open air ; but I had already 

 ascertained that these worms will remain in air for many hours, 

 without seeming to suffer any inconvenience. 



** I had a number of specimens lying on a plate motionless ; for, 

 unless disturbed, they are little inclined to move. I dipped my hand 

 in fresh water, and with a jerk, sprinkled some drops of it over the 

 plate, and the specimens on it. In about two seconds the worms 

 were all in violent agitation, rolling round on the longitudinal axis of 

 their bodies, and writhing together in apparent agonies. After a 



