( 83 ) 



lieart, and that the rapid motion of the parts round about it, which 

 I obferved in this animalcule, and the motion which I had feen in 

 the others, proceeded from the action of the heart. 



Upon obferving in one of thefe animalcules eight or nine greenifli 

 particles I began to think that thofe were unborn young ones ; to 

 afcertain which I put one of the animalcules into a little w^ater, be- 

 ing the quantity of five or fix drops, that I might thereby fee the 

 young when newly ilTued from the parent and fwimming in the wa- 

 ter : but the next day, finding the animal dead, I opened its body 

 -while lying in the water, and then I not only very plainly law molt 

 of the unborn young ones, but I could alio difcern the organs or 

 limbs provided for their ufe in fwimming. 



This animalcule was of fuch a pretty ihape, that I often viewed 

 it with great admiration : indeed, I was fo much pleated with its 

 formation, that I thought larger animals viewed with the naked eye 

 would, in companion with this, appear rudely made.* The death 

 of this creature feemed to me to be caufed by want of food, becaufe 

 I had feen it frequently void its excrements, w^hence I concluded 

 that it required a large fupply of nutriment in proportion to its fize. 



After this I difcovered another fpecies of animalcule, almoft of 

 .the fame fize with the former ones, but of entirely dilFerent make. 

 This animalcule had a long forked tail, and each of the forked parts 

 again divided into foTu- parts, which laft parts were provided with 



various organs. 



But obferving one of thefe animalcules, (though of the fame fpe- 

 cies), to appear as if the hind part of its body was formed in a very 

 different manner, I put two of them into a fmalJ portion of water, 

 in order to examine them by a microfcope of greater magnifying 



* This beinj; Ihc cafe, it fceras flrangc that Mr. Lceuwcnlioek has not gl?cn a figure of this 

 animalcule ; from the account here given of it, and particularly the motion of its heart, rt 

 flioiiUl fi;'m to be of tlic fpecies railed pnlex aquaticus, or water fica, of wiiich a fiuure, as 

 f en through the microfcope, with a del'cription of the cre.iturcj will be found in Bjtei's 

 ilinploymcnt for the Microfcope. 



L 2 



