IN THE BODIES OF ANIMALS. 397 



I took the remainder, broke the shells, and found in all the 

 young, numbers of pieces of Tcenice, although I looked in 

 vain for the other species ; viz. the Ascaris and Distoma. 

 The Tcenim were so completely enveloped in the thick 

 mucus contained in the intestines, that they would certainly 

 have eluded my observation had I not diffused the contents of 

 the canal in clear water. I am not aware that this fact has been 

 noticed before ; if any of your readers are aware of similar 

 cases, they would confer a benefit upon science by publishing 

 them. I doubt not but that it is universal, and that if sufficient 

 care is exercised in making the investigation, that they will be 

 found in every instance. I intend, at a future time, if leisure 

 and opportunity permit, to pursue the inquiry further, and to 

 examine at what earliest period of fcetal life worms can be de- 

 tected ; but I think enough has been already adduced to prove 

 the fallacy of the hypothesis which refers their existence to an 

 external source. And here the question rests at present. And 

 is it not far better that, in the absence of facts, the question 

 should be thus suspended, than that a hasty inference should 

 be formed which future observations may invalidate? If, then, 

 they are innate, whence do they originate ? Are they trans- 

 mitted to the foetus through the medium of the male or female 

 parent ? I am constrained to the belief that this is not proba- 

 ble. I shall examine into the possibility of communication by 

 the male parent, more for the sake of avoiding a charge of par- 

 tiality than for any other reason. A few words, however, will 

 suffice, as it is above all other theories most foreign to the 

 truth, and is now hardly supported by any one. The male 

 parent does indeed vivify the germ of the future offspring, and 

 as it were impart to it a spark of the quickening fire ; but it is 

 on the mother that the vivified germ depends for all its growth 

 and development. The ova of amphibious animals, fishes, &c. 

 are deposited by the female parent, and are subsequently called 

 into life by the contact of the male fluid ; nor, indeed, does 

 actual coition take place in the majority of animals. Whether 

 these ova absorb the seminal particles or not, is a question 

 which I cannot solve; but the experiments of Spallanzani prove 

 that the infinitesimal portion of semen is sufficient for fecun- 

 dation. Having diffused three grains of frog's semen in two 

 pounds of common water, he found that every particle of the 

 water possessed the fecundating power ; for on applying a 



