“6 SEMINAL VERMICULI. i. 
Two other objections are ftill to be appretiat- 
ed; one deduced from the fingular motion of fe- 
minal vermiculi; the other from the different ef- 
feéts of heat and cold uponthem. Let us attend 
to the firft. An animal, according to M. de Buf- 
fon’s reafoning, is fubject to change its inclina- 
tions. Sometimes its motion is quick, fometimes 
flow, then it ftops and refts. But nothing of 
this occurs in feminal vermiculi: they are in 
continual motion, never reft, and, when once they 
ftop, it is for ever. Hence they cannot be ani- 
mals. This objection is, like the former, both be- 
ing founded on the analogy of the large animals 
beft known to us; which, as they do not change 
their fhape, naturally have the viciflitudes of 
reft or motion, of accelerated motion, or the 
like. But to admit that fuch viciffitudes are cer- 
tainly a characteriftic quality of animals, it is im- 
proper to confider thefe alone; it is neceflary to 
examine other genera and other fpecies, and to 
dwell particularly on the fmalleft, efpecially thofe 
inhabiting fluids which have more analogy to 
fpermatic vermiculi. It is undoubted, that a- 
mong them M. de Buffon would have found 
feveral animals, which, far from having the alter- 
natives of motion and reft, are naturally in mo- 
tion; fo that their life feems ta confift in a per- 
petual motion. To afcertain the fact, it is necef- 
fary, during fummer, to obferve the water of 
marfhes, 
