192 ORGANISED FLUIDS. 



from fifteen to twenty minutes * ; occasionally, nevertheless, 

 the spermatozoa have been found moving in birds which have 

 not been opened until some hours have elapsed after death : 

 those of the Mammalia have been observed in motion for a 

 very long period after the removal of the semen from the 

 testicle, and after the death of the animal ; but it is in fishes 

 that the spermatozoa retain their powers of locomotion out 

 of the body for the longest period, even for many days. 



According to Dujardin f , the spermatozoa live thirteen 

 hours in the testicles of the mammalia after the death of the 

 animal. 



LamperhoffJ has found living semen in the vesicuta se- 

 minales of dead men, in which the spermatozoa retained the 

 power of locomotion for twenty hours. 



Wagner has observed them exhibiting motion at the end 

 of twenty -four hours. 



Donne || states that he has watched their movements for 

 an entire day, and that he has observed them in motion even 

 on the second day. 



It is, above all, in the place of their final destination that 

 the spermatozoa live for the longest period ; thus, Leeuwen- 

 hoek first, and other observers subsequently, have discovered 

 them in a living condition in the uterus and Fallopian tubes 

 of a bitch seven days after connexion IF, and Bischoff** has 

 found them alive eight days after intercourse in the rabbit. 



The great length of time during which, under certain cir- 

 cumstances, the spermatozoa retain the faculty of locomotion, 

 furnishes another strong argument in favour of their inde- 

 pendent vitality. 



Effects of Reagents. 



The seminal animalcules retain their locomotive powers 

 for a very long time in fluids of a bland nature, for ex- 



* Wagner, loc. cit. p. 21. f Annales des Sciences Nat. 



\ Diss. de Vesical. Semin. Loc. cit, p. 22. 



|| Cours de Microscopic, p. 284. ^[ Opera omnia, t. 1. b. p. 150. 

 ** Muller, Archiv. p. 16. 1841. 



