36 PHILOSOPHICAL TRANSACTIONS. [aNNO 1703. 



I preserved some of this dunghill-water by me 7 or 8 days, and found the 

 number of these little eels decreasing every day, till I could hardly find one in 

 it, though they were as plentiful as before in the water newly taken up. And, 

 on the contrary, I observed great numbers in the kept water, which are very 

 scarce in the fresh. Among these is one sort very singular in its shape and 

 motions: its body is spherical, only a little pointed like a pear, and it seems 

 very pliable, like a bladder filled with water, in which are a vast number of dark 

 particles in confused agitation. Their most remarkable motion is a revolving 

 one; they will turn sometimes above 100 times, sometimes not half so fast, in 

 a minute, the same way, and then stop and turn the contrary way, and all this 

 without moving a hair's breadth out of their place. They will also go forward, 

 turn and return, and fetch a large compass with many deviations, and in their 

 progression they always, even in the shortest turns, keep their pointed end fore- 

 most, the revolving motion still continuing: and when the water evaporates, 

 their skin breaks, and the enclosed liquid diffuses. These are of different mag- 

 nitudes, and their shapes appear at l. 



There is another sort, represented at m, in great numbers, which are near as 

 long as the largest kind formerly mentioned. These have brisk motions, are 

 very active, and have many feet before, very visible. They will often contract, 

 and again lengthen themselves as they swim, but especially when the water 

 dries, they will shrink themselves up into a globular figure, and the feet then 

 stand out, which may be seen to move very nimbly a considerable time after. 

 These also are of different sizes: a a show them at their length, and bb repre- 

 sent them contracted. 



Fig. N represents another animal, not uncommon among the rest, which 

 is as large as the former, and in its motion, which is very nimble, keeps always 

 the sharp end foremost. I have observed some variety in these, though I take 

 them to be of the same species; some of them being clear, and curiously 

 striated, from the point to the thick end; others only having a fore-part clear, 

 and the bottle dark, as shown at a and b; but I cannot by any glass find the 

 organs by which they move. 



These now mentioned are the most remarkable for their size and motions ; 

 but there are a great variety of others, which I pretend not to describe, and can- 

 not draw. In one I found a curious mechanism in a small diving insect, found 

 in standing waters. It is like a small fly, with a head like a house cricket; but, 

 instead of wings, it has 2 paddles on the shoulders, and on the end of the 

 hinder legs, which are longer than the other 4, instead of feet and claws are 

 perfect oars. I have also observed in 2 or 3 sorts of flies, that behind the eyes, 

 on the top of the head, are placed three protuberances, with a black shining 



