OF THE FOETUS. 279 



Few anlmls are endowed, like fnails, with both 

 fexes ; and, therefore, if this mode of propa- 

 gating were the mod fimple, it would be more 

 generally employed by Nature, This folution^ 

 of courfe, amounts to no more than a gratuitous 

 fuppofition, that males produce not, folely be- 

 caufe they have not organs proper for contain- 

 ing and nourifhing a foetus. 



It may be ftill farther fuppofed, that the a£li- 

 vity of the organic particles in the femen of each 

 individual requires to be counterbalanced by the 

 force or adion of thofe of the other individual^ 

 in order to reduce them to a fixed ftate, or e- 

 quilibrium, without which the formation of the 

 foetus cannot be efFeded ; and that the motion 

 of the organic particles of the female cannot be 

 counterbalanced by any other caufe than a con- 

 trary adion in the'organic particles received from 

 the male. But this anlwer is too general to be 

 void of obfcurity. However, when we attend 

 to all the phaenomena, it may, perhaps, admit 

 of lome illuftration. The mixture of the two 

 feminal fluids produces not only a male or fe- 

 male foetus, but other organized bodies, which 

 are endowed with the faculty of growth or ex- 

 panfion. The placenta, the membranes, Sec. 

 are produced at the fame time, if not fooner, 

 than the foetus. There are, therefore, in the 

 feminal fluid of the male or female, or in the 

 mixture of both, organic particles not only 

 fuited to the produdion of the foetus, but of the 



placenta 



