SECT. 197.] ON THE SPERMATOZOA. 435 



circumstances. In the dead body, they are not unfrequeutly 

 observed twelve to twenty-four hours after death ( Valentin once 

 >:nv Blight movements after eighty-four hours). In the female 

 genitals in mammalia, they continue to move even after seven and 

 eight days. Water and all diluted solutions, render the move- 

 ments more active at first ; but they soon cease, and the filaments 

 not unfrequeutly roll up in the form of loops: the spermatozoa, 

 however, are not then dead, as has hitherto been believed, for they 

 will resume their activity, as I have proved, on the addition of con- 

 centrated solutions of salts, sugar, albumen, or urea. All animal 

 fluids of an alkaline reaction and moderate concentration, are 

 favourable to the movement of the filaments, while acid solutions 

 or those which are too weak — such as urine, sour milk, sour mucus, 

 diluted bile — exercise an injurious effect upon them. Solutions 

 of substances of a more neutral character, such as sugar, albumen, 

 glycerine, amygdalin, or urea, are harmless if they are of a me- 

 dium degree of strength, but are injurious if they are too concen- 

 trated or too diluted. In either of the latter cases, the suspended 

 movements can be restored by bringing the solution to a suitable 

 degree of dilution. In a similar way, the spermatozoa are effected 

 bv the neutral salts of the alkalies : common salt in a solution of 

 one per cent., Glauber's salts, or Epsom salts, in a solution of 

 three per cent., are all favourable to their movements. Stronger 

 or weaker solutions suspend the movements, though these may be 

 restored in the way before mentioned. Acids, metallic salts, and 

 caustic alkalies, are harmful to the movements of the spermatozoa, 

 though it appears from my observations, that the injurious influ- 

 ence of the last-named reagents is preceded by a period of excite- 

 ment, of more active motion, so that caustic potash and soda 

 might be taken for special excitors of the filaments. Narcotic 

 substances only act injuriously when they have some chemical 

 influence on the semen, or when they are of an unsuitable degree 

 of dilution. Alcohol, aether, oil, creosote, chloroform, tannin, 

 among other matters, have been found to injure the movements. 

 For further detail, the reader may consult my treatise and the 

 researches of Quatrefages. The effect of cold is to suspend the 

 movements, and a temperature of 42 to 45 Reaumur (n 6° to 

 124 Fahr.) has a similar result : but spermatozoa whose move- 

 ments have been arrested by cold, will move again on a return of 

 warmth, if the temperature have not been reduced too low. 



The formation of the spermatozoa and semen ceases, as a rule, 



f f 2 



