Sect. XXXTX. 4. 8. GENERATION. 35? 



admired for their peculiarities, which are monfters thus produ- 

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

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

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



When we coniider 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- 

 iryon is formed by appofition of new part.>, and not by the dis- 

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

 .other, like the cups of 2 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 3 

 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- 

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

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

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

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

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

 in the horfe. While in the bird Jund 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 initead of teeth in the fore part of the upper jaw ; in 

 others tuihes inftead ofiiorns ; and in others beaks inftead of 

 .either. And all this exactly as is daily feen in the tranfmuta- 

 tions of the tadpole, which acquires legs and lungs, when he 

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

 to him. 



Fifthly, from their firfi rudiment, or primordium, to the ter- 

 mination of their lives, ail animals undergo perpetual transform- 

 ations ; which are in part produced by their own exertions in 

 confequence of their defires and averfions, of their pleafures and 

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

 thefe acquired forms or propenfities are tranfmitted to their 

 pofterity. See Sect. XXXI. 1. 



As air and water are fupplied to animals in fumcient profu- 

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

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

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

 of the animal world has confifted 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, fhield-like, 

 horny Ikin on the moulder of the boar is a defence only againft 



animal^ 



