38 NATURAL HISTORY. 



cause of the great difference of times amongst living 

 creatures, is either from the nature of the kind, or 

 from the constitution of the womb. For the former, 

 those that are longer in coining to their maturity or 

 growth are longer in the womb ; as is chiefly seen in 

 men : and so elephants, which are long in the womb, 

 are long time in coming to their full growth. But in 

 most other kinds, the constitution of the womb (that 

 is, the hardness or dryness thereof,) is concurrent 

 with the former cause. For the colt hath about four 

 years of growth ; and so the fawn ; and so the calf. 

 But whelps, which come to their growth (commonly) 

 within three quarters of a year, are but nine weeks 

 in the womb. As for birds, as there is less diversity 

 amongst them in the time of their bringing forth, so 

 there is less diversity in the time of their growth ; 

 most of them coming to their growth within a 

 twelvemonth. 



760. Some creatures bring forth many young ones 

 at a burthen : as bitches, hares, coneys, &c. Some 

 (ordinarily) but one ; as women, lionesses, &c. ] This 

 may be caused, either by the quantity of sperm re 

 quired to the producing one of that kind ; which if 

 less be required, may admit greater number ; if more, 

 fewer: or by the partitions and cells of the womb, 

 which may sever the sperm. 



Experiments in consort touching species visible. 



761. There is no doubt but light by refraction will 

 shew greater, as well as things coloured. For like as 



turkey-hen about twenty-seven, the duck and goose thirty to thirty-two 

 days. The hen, as Bacon says, about three weeks. See Tessier and F. 

 Cuvier, ubi supra, 

 i Arist, Prob. x. 16. 



