282 MR. NEWPORT ON THE IMPREGNATION OF THE OVUM IN THE AMPHIBIA 



matozoon has penetrated through the envelopes and arrived at the vitelline membrane, 

 or the yelk i Or is it by its expenditure on the yelk, of aforce or power of vitality, which 

 is inherent in the body of the spermatozoon ? Or is it by the joint cooperation of both 

 these conditions the expenditure of aforce with diffluence of material substance ? I 

 have endeavoured to put the first of these questions to the test of experiment ; 

 although, it must be remarked, that the experiments made seem to be open to some 

 objections, which at present cannot be fully answered. Yet knowing what we do of 

 the disposition and great readiness of all matter to enter into new combinations, and 

 affect, or entirely change the condition of the whole body operated upon, as, not 

 to mention the effect of the poison of serpents, or the introduction of dead matter into 

 the living, in dissection, can be shown in the effect, on the yelk of the Frog's egg, 

 of extremely minute quantities of chemical compounds diffused in water, there has 

 seemed fair reason to think that the question thus started may be examined by 

 experiment. The rapid endosmic action of the envelopes of the egg at the instant of 

 their contact with any aqueous fluid, and the rapidity with which the yelk itself then 

 becomes affected, seemed to favour the idea that if the bodies of the newly obtained 

 spermatozoa could be quickly reduced to a state of diffluence simply by mechanical 

 means, without the addition of any menstruum, saving only a very small quantity of 

 water, and be applied in this state of diffluence to the egg at the instant after it has 

 left the body of the female, that then an experiment thus made would be a fair test 

 of the question. Some imbibition of the substance of the spermatozoon with the 

 water might thus be expected to take place, and some changes in the egg to follow, 

 if impregnation be the result of simple chemical combination of the substance of the 

 male with that of the female. The presence in the experiment of a portion of water 

 holding the diffluent spermatic substance in suspension, appeared at first sight to 

 be an objection, but this seemed to be met by the fact that water must always be pre- 

 sent to ensure the natural fecundation of the Frog's egg ; and that it not only perme- 

 ates the envelopes, and is the means of facilitating the entrance of the spermatozoon, 

 but that it passes even to the substance of the yelk itself, as shown in the experiments 

 with large quantities of potass before alluded to, and also in others made by immer- 

 sion of eggs in water with given proportions of potass in solution. As the details of 

 these latter experiments are contained in a paper which is now in the Archives of 

 the Royal Society*, I need give but little more than the results of these experiments, 

 in the present communication, before proceeding to relate those now referred to with 

 the diffluent spermatozoa. 



Immersion of Ova in Solutions of Potass and Soda. These experiments were 

 commenced in April 1850, before the publication of some which were made with 

 solutions of caustic potass, by M. QUATREFAGES, on the spermatozoa of one of the 

 marine worms, Hermella, and read to the Institute on the 24th of June 1850-f-. 



* MS., No. 762. p. 13 to 26; also Proceedings, vol. vi. p. 83. 



f Comptes Rendus, June 24, 1850, and Annales des Sciences Naturelles, 3 m ' s6rie, torn. xiii. in Nos. 

 marked " February " and " March 1850." 



