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Show 404 ACTION OF MALE ELEMF.NT. CHAP. XI. two colts by a black Arabian horse. These colts were yartially dun-coloured, and wore striped on the legs more plamly than the real hybrid, or oven than the quagga. One of ~he two colts had its neck and some other parts of its body plamly marked with stripes. Stripes on the body, not to mention tho e on ~he legs, and tho dun-colour, arc extremely raro,-I speal~ aft?r having long atte11ded to the subjcct,-with hors~s of alllnnds m Europe, and are unknown in tho case of Arabians. ~ut what makes tho case still more striking is that the hau of tho mane iu these colts resem blerl that of the quagga, being short, stiff, and upright. Hence there can be no doubt that tho quagga affected tho character of the offspring subsequently begot by the black Arabian horse. With respect to the Yariotios of our domesticated animals, many similar and wcll-authenticatorl facts have been published,138 and others have been communicated to me, plainly showing tho influence of the first male on tho progeny subsequently borne by the mother to other males. It will suffice to give a single instance, recorded in the ' Philosophical 'rransactions,' in a paper following that by Lord Morton: Mr. Giles put a sow of Lord Western's black and white Essex breed to a wild boar of a deep chesnut colour; and tho " pigs produced partook in appearance of both boar and sow, but in some tho chesnut colour of the boar strongly prevailed." After tho boar bad long boon deacl, the sow " ·as put to a boar of her own black and white breed,-a kind which is well known to breed very true and never to show any chesnut colour,-yet from this union the sow produced some young pigs which were plainly marked with tho same chesnut tint as in the first litter. Similar cases have so frequently occurred, that careful breeders avoid putting a choice female to an inferior male on account of tho injury to her subsequent progeny whieh may be expected to follow. 138 Dr. Alex. Harvey on 'A remarkable Effect of Cross· breeding,' 1851. On the ' Physiology of Breeding,' by Mr. Reginald Orton, 1855. • Intermarrio.gc,' by Alex. Walker, 1837. 'L'Hcredite Naturelle,' by Dr. Prosper Lucas, tom. ii. p. 58. Mr. W. Sedgwick in 'British o.ndForcignMcdico·Chirurgico.lRcvicw,' 1863, July, p. 183. Bronn, in Ids 'Gcschichtc der Natnr,' 184.3, B. ii. s. 127, has collected several cases with respect to mares, sows, and dogs. Mr. W. C. L. Martin ('History of the Dog,' 1845, p. 104) says he can personally voucl1for the influence of tho mnle parent of the first litter ou the subsequent litters by other fathers. A French poet, Jacques So.vary, who wrote in 16G5 on dogs, was aware of this singulo.r fact. CnAP. xr. SUMMARY OF TIIE CITAPTER. 405 Somo physiologists have attempted to account for these remarkable results from a first impregnation by the close attachment and freely intercommunicating blood-vessels between the modified embryo anfl the mother. But it is a most improbable hypothesis that the mere blood of one individual should affect the reproductive organs of another individual in such a manner as to modify the subsequent offspring. The analogy from the direct aetion of foreign pollen on the ovarium and seed-coats of tho mother-plant strongly supports the belief that the male element acts directly on the reproductive organs of the female, wonderful as is this action, and not through the intervention of the crossed embryo. With birds there is no such clo e connection between the embryo and mother as in the case of mammals: yet a careful observer, Dr. Chapuis, states 139 that with pigeons the influence of a :first male sometimes makes itself perceived in the succeerling broods; but this statement, before it can be fully trusted, requires confirmation. Conclusion and Summary of the Chapter.-The facts given in the latter half of this chapter are well worthy of consideration, as they show us in how many extraordinary modes one organic form may lead to the modification of another, and often without the intervention of seminal reproduction. There is ample evid~ nco, as we have just seen, that the male element may either dn·octly affect the structure of the female, or in the case of animals lead to the modification of her offspring. There is a c?nsiderable but insufficient body of evidence showing that the tissues of two plants may unite and form a bud having a Llended character; or again, that buds inserted into a stock may affect all the buds subsequently produced by this stock. Two embryos, differing from each other and contained in the same seed, may cohere and form a single plant. Offspring from a cross between two species or varieties may in the :first or in a. succeedin?' generation revert in various degrees by bud-variatiOn to theu parent-forms; and this reversion or segregation of character may affect the whole flower, fruit, or leaf-bud, or only tho half or smaller segment, or a single organ. In some cases this segregation of character apparently depends on some 139 'Le Pigeon Voyageur Beige,' 1865, p. 59. |