R C. PUNNBTT AND TIIK LATK P. il. HaII.KV 15 



uf maturity is cU>Ht»ly com»laUHl with hv/.v, Thr vt-ry Hinall PoHmH mhhit 

 inattm'8 slowly — |in»hably a ginnl t\vi\\ mnn- hIowIv than a lar^rr fonn 

 such as the Dutch. 



(3) Sixe and early maturity an ' to sunu* rxti'iit traiif*ii»itt<<l iinl«'- 

 pi'mleiitly. Karly maturing lar^t* aniuials i\h wrlj ]im latr iiiiitiiriti)^ Miiall 

 *»iie8 may occur U>^ethiT in the same F., family after a <-rosM. 



(4) CiXKSsing (iislincl biveds n»ay in some vast's ha*! to \» ly rarly 

 maturity in F^. In other ouses this (Uh's not appear to In- tiJu-. 



The data taken t^j^ether su^j^est that early maturity may <lf|H'nd 

 u|>on st)mi» factor, or factors, indrjK'ndcnt <>f size, thnu;(h probably a 

 larger nibbit wouM mature later than a smaller one where both wen- 

 similarly eonstitut<?d with regaixl to th»' sjK'ciHc genetic taetoi-s u|Hin 

 which onsi»t of maturity di'jK'iuled. The [)resent <lat^i are far to<» slender 

 for [Mjsitive infercnce, and we do not pretend that they oti'er more than 

 an indicjition of a pn>Ht{ible line of encpiiry for the future. 



Sexual Differences. 



A. Mature Weig/U. It is well known that in many animals the 

 male is normally the heavier of the two sexes when mature. This is 

 probjibly true of the majority of mammals, and there is cxjx'riment.d 

 evidence that it is also true for certain birds'. It is not, however, tru** 

 for nibbits. Our data shew that in some ca.ses the average weight of 

 bucks and does from a given jmir of rabbits is approximately e(jual : in 

 other cjises the average weight of the doe is markedly greater than that 

 of the buck. In no Ciise which has come under our notice does the buck 

 certainly exhibit the marked preponderance which may occur in the doe. 

 The position may be indicated by the following abstract (Table A) of 

 the datii contained in Tables I-V. 



The figures shew that on the whole there is no marked difference 

 between the sexes in the Flemish. Indeed they shew an actual e<piality 

 for the whole of the animals reconled. This equality is however to be 

 discounteil by the fact that a larger proportion of males than of females 

 belongs to the earlier generation when the weights for both sexes were 

 considerably higher (cf. Table I, p. 21). For the later g<'nerations c<»ii- 

 sidered apart the average wi'ight of the females is rather higher than 

 that of the males. We are inclined to the view that our original 

 Flemish were of mixed constitution with regard to weight factoi-s (w hat- 

 ever these may be) and that the preponderance of weight among the 



» Cf. Darwin ('91) ii. p. 281 ; Donaldson (15) ; Phillips ('12) ; I'unnett and Bailey ('li). 



