568 GENERATION. SECT. XXXIX. 4. 



labour at the anvil, the oar, or the loom, as well 

 as thofe who carry fedan-chairs, or who have been 

 educated to dance upon the rope, are diftinguifh- 

 able by the fhape of their limbs ; and the difeafes 

 occafioned by intoxication deform the countenance 

 with leprous eruptions, or the body with tumid 

 vifcera, or the joints with knots and diftortions. 



Thirdly, when we enumerate the great changes 

 produced in the fpecies of animals before their na- 

 tivity ; thefe are fuch as referable the form or co- 

 lour of their parents, which have been altered by 

 the cultivation or accidents above related, and are 

 thus continued to their pofterity. Or they are 

 changes produced by the mixture of fpecies, as in 

 mules ; or changes produced probably by the exu- 

 berance of nourishment fupplied to the fetus, as in 

 monftrous births with additional limbs; many of 

 thefe enormities of fhape are propagated, and con- 

 tinued as a variety at leaft, if not as a new fpecies 

 of animal. I have feen a breed of cats with an ad- 

 ditional claw on every foot ; of poultry alfo with 

 an additional claw, and with wings to their feet ; 

 and of others without rumps* Mr. Buffon menti- 

 ons a breed of dogs without tails, which are com- 

 mon at Rome and at Naples, which he fuppofes to 

 have been produced by a cuftorn long eftablifhed 

 of cutting their tails clofe off. There are many 

 kinds of pigeons, admired for their peculiarities, 

 which are monflers thus produced and propagated, 

 And to thefe muft be added, the changes produced 

 by the imagination of the male parent, as will be 

 treated of more at large in No. VI. of this Section* 



When we confider all thefe changes of animal 

 form, and innumerable others, which may be col- 

 lected from the books of natural hiftory ; we can- 

 not but be convinced, that the fetus or embryon is 

 formed by apportion of new parts, and not by the 



diftention 



