SECT. XXXIX. 4. 8. GENERATION. 395 



admired for their peculiarities, which are monflers thus produ- 

 ced and propagated. And to thefe muft be added, the changes 

 produced by the imagination of the male parent, as will be treat- 

 ed of more at large in No. VL of this Section. 



When we confider all thefe changes of animal form, and in- 

 numerable others, which may be collected from the books of nat- 

 ural hiftory ; we cannot but be convinced, that the fetus or em- 

 bryon is formed by apportion of new paits, and not by the dif- 

 tention of a primordial neft of germes, included one within an- 

 other, like the cups of a conjurer. 



Fourthly, when we revolve in our minds the great fimilarity 

 of ftrufture which obtains in all the warm blooded animals, as 

 well quadrupeds, birds, and amphibious animals, as in mankind ; 

 from the moufe and bat to the elephant and whale ; one is led 

 to conclude, that they have alike been produced from a fimilar 

 living filament. In fome this filament in its advance to maturi- 



o 



ty has acquired hands and fingers, with a fine fenfe of touch, -ns 

 in mankind. In others it has acquired claws or talons, as in 

 tygers and eagles. In others, toes with an intervening web, or 

 membrane, as in feals and geefe. In others it has acquired clo- 

 ven hoofs, as in cows and fwine ; and whole hoofs in others, as 

 in the horfe. While in the bird kind this original living fila- 

 ment has put forth wings inftead of arms or legs, and feathers 

 inftead of hair. In fome it has protruded horns on the fore- 

 head inftead of teeth in the fore part of the upper jaw ; in 

 others tudies inftead of horns ; and in others beaks intend of 

 either. And all this exa6lly as is daily feen in the trail fr.- 

 tions of the tadpole, which acquires legs and lungs, W!K J 

 wants them ; and lofes his tail, when it is no longer of fervice 

 to him. 



Fifthly, from their fir ft rudiment, or pvimordium, to the ter- 

 mination of their lives, all animals undergo perpetual transform- 

 ations ; which are in part produced by their own cxerrio 

 confequence of their defires and averfions, of their pleafures. and 

 their pains, or of irritations, or of ailbciations ; and many of 

 thefe acquired forms or propenfities are tranfmitted to their 

 pofterity. See Sea. XXXI. i. 



As air and water are (applied to animals in fufficient profu- 

 fion, the three great objects of defire, which have changed the 

 forms of many animals by their exertions to gratify them, are 

 thofe of luft, hunger, and fecurity. A great want of one part 

 of the animal world has confided in the defire of the exclufive 

 pofleflion of the females ; and thefe have acquired weapons to 

 combat each other for this purpofe, as the very thick, fliield-Iike, 

 horny fkin on the ihoulder of the boar is a defence only againt'k 



animals 



