If, SEMINAL VERMICULI. ^ot 



the middle of the fpine. One end is fixed near the 

 head of the animal j the aperture of the other is 

 evidently in the cloaca, through which the excre- 

 ment pafles. The velTels are always full of fe- 

 men, particularly while the males fecundate the 

 eggs of the females. The femen is very white^ 

 like milk, and the number of corpufeula it con- 

 tains is fo great that the fluid part is fmall' com- 

 pared with the mafs they form. They are per- 

 fectly fimilar to thofe in the feminal fluid of the 

 tefticles ; with this difference, however, that 

 neither water nor any other liquid is require 

 ed to increafe their motion. In the femen, they 

 naturally move with the quicknefs of the corpuf- 

 eula in fluid from the tefliicles diluted with water. 

 The corpufeula of the vafa deferentia retain mo- 

 tion much longer than thofe of the tefl:icles ; yet 

 it is far from equal to that of the human corpuf- 

 eula, thofe of the horfe and other animals, I 

 have always found them in male newts in every 

 feafon of the year. 



By exprefling the feminal fluid from the tefti- 

 cles of frogs, it is vifibly full of corpufeula. They 

 are infinitely fliorter than thofe of the newts. 

 They have progreflion, and in advancing make 

 gentle vibrations. They are of a long elliptical 

 fliape, and very foon ceafe to move, fig. 8, Plate 



CHAP.. 



