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Show 90 CATTLE. CHAP. JII. . t tact with the premnxillaries. curved upwards to come m o con. rdinar len th but 1'hc nasal bones are about one-thml the o . y g : .. . . . 1 b. adth The tnangular vacmty IS retam almost their nOiml;t re · . 1 b I f . t 1 and lachrymal wbwh attcr one left between them, t 1e ron a ' . .1 articulates with the premaxillary, and thus exeluubes the maxthl - lary from any J.U ilCti.O n wi· t h the nasa1 . " So t at e. ven e conllCXJ.O n f f th bones is changed. Other d1fforences 0 some 0 e . h might be added: thus the plane of the condy~es ~s s~mew at modified, and the terminal edge of the premaxJllancs forms an arch. In fact, on comparison with the skull of a common ox, scarce l y a sm· g· lo bone presents . the same exact shape, and the whole skull has a wonderfully different appearance. 1'be :first brief published notice of this ra~e was by Azara, between the years 1783-96; but Don F. Uumz, of Luxan, w~o bas kinuly collected information for me, states that about 1760 these cattle were kept as curiosities near Buenos Ayrc~. rrheir origin is not positively known, but they must have Originated snbs quently to tho year 1552, when cattle. were. :first introduced. Signor Muniz informs me that the brecc~ 1s boheved to have originnted with the Indians southward of the ~lata. Evon to this day those roared near the Plata show the~r less civilized nature in being :fiercer than common cattle, and m the cow if visited too often, easily deserting her first calf. The bre~d is very true, and a niata bull and cow invariably produce niata calves. The breed has already lasted at least a century. A niata bull crossed with a common cow, and the reverse cross, yield offspring having an intermediate charac~or, but . '''ith the niata character strongly displayed. Accordtng to S1gnor 1\Iuniz, there i. tho clearest evidence, contrary to the common belief of ::wriculturists in analogous cases, that tho niata cow when cross~d with a common bull transmits her peculiarities more strongly than does the niata bull when crossed with a common cow. When the pasture is tolerably long, these cattle feed as well as common cattle with their tongue anu palate; but dnring the groat droughts, when so many animals perish on the Pampas, the niata breed lies under a great disadvantage, and would, if not attended to, become extinct ; for the common cattle, like horse , are able just to keep alive by browsing on the twigs of trees and on roods with their lips: this the niatas cannot so CHAP. III. CAUSES OF V .A.RI.A.TION. 91 well do, as their lips do not join, and hence they are found to perish before tho common cattle. This strikes me as a good illustration of how little we are able to judge ~rom the ordinary habits of an animal, on wlwt circumstances, occurring only at long intervals of time, its rarity or extinction may depend. It shows us, also, how natural selection would have determined the rejection of the niata modification had it arisen in a state of nature. Having described the semi-monstrous niata breed, I may allude to a white bull, said to have been brought from Africa, which was exhibited in London in 1829, and which has Leen well :figured by Mr. Harvey.67 It had a hump, and was furnished with a mane. The dewlap was peculiar, being divided between its foro-legs into parallel divisions. Its lateral hoofs were annually shed, and grew to the length of five or six inches. The eye was very peculiar, being remarkably prominent, and "resembled a cup and ball, thus enabling the animal to see on all siclos with. equal ease ; the pnpil was small and oval, or rather a parallelogram with the ends cut off, and lying transversely across the balL" .A. new and strange breed might probably have been formed by careful breeding and selection from this animal. I have often speculated on the probable. causes through which each separate district in Great Britain came to possess in former times its own peculiar breed of cattle ; and tho question is, perhaps, even more perplexing in the case of Southern Africa. Vv o now know that the differences may be in part attributed to descent from distinct species ; but this will not suffice. Have the slight differences in climate and in the nature of the pasture, in the different districts of Britain, directly induced corresponding differences in the cattle? We have seen that the semi-wild cattle in the several British parks are not identical in colouring or size, and that some degree of selection has been requisite to keep them true. It is almost certain that abundant food given during many generations directly affects the size of a breed. 68 That climate directly affects the thickness of the 67 Loudon's' Magazine of Nat. Hist.,' vol. i:, 1829, p. 113. Separate figures are gtven of tile animal, its hoofs, eye, and dewlap. 68 Low, 'Domesticated Animals of the British Isles,' p. 264. |