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ART. XII.-ON CONSOLIDATION OF THE HOOFS IN THE VIR

GINIAN DEER.

BY DR. ELLIOTT COUES, U. S. A.

Mr. George A. Boardman, of Calais, Me., has obligingly submitted to my examination the feet of a Deer (Cariacus virginianus) displaying the abnormality of consolidation of the hoofs.

The state of the specimens does not permit any examination of the condition of the bones themselves. As well as can be judged from inspection, and by feeling through the dried skin which covers them, they are entirely normal.

The false hoofs are present and of ordinary characters.

The malformation seems to be confined to the horny substance of the true hoof, which is consolidated with its fellow of the opposite. The union is complete along the whole inner margius of the hoof, excepting a notch between the two halves at the end less than half an inch in depth.

Viewed from above, the hoof shows its composition by lateral halves, there being a profound longitudinal sulcus, along the bottom of which groove is the line of union, complete to within less than half an inch of the end.

On the plantar surface, the confluence of the hoofs gives a nearly plane surface, without special indication by a sulcus of the line of union, to within about an inch of the end, where a median depression, bounded by raised edges, marks the seam, the extremity being nicked, or notched, as already said. The outer border of the sole of the foot is smoothly rounded off behind; but anteriorly, for about half the length of the whole hoof, the margins are raised and sharp-edged, this edge terminating behind in a scroll-like inversion. This sharp margin is the outer edge of each hoof along that portion of its length which is ordinarily applied to the ground.

The profile view of the hoof displays the deformity of excessive growth in length, the whole hoof being unnaturally elongated, with the end curved upward, rendering the fore border strongly concave in profile, and causing the hind and under border to fall into one long and continuous curve, with convexity downward.

Besides such elongation and curvature, the whole hoof is unnaturally contracted, or laterally compressed; the sides, which should expand downward and outward, curving downward and toward each other, so

that the greatest width of the plantar surface between the lateral sharp edges is much less than the diameter of the hoof across the top.

Length of the hoof in front (chord of the concave border) nearly two inches. Entire length of the hoof behind (chord of the convex curve from base to tip) three inches. Greatest width of the hoof, both halves together, less than one inch-this measurement being taken near the base of the hoof behind. Width of either half, at a point opposite ends of the hairs in front, only four-tenths of an inch.

The general constriction of the hoof is of course of a part with its consolidation; while its lengthening and curvature are doubtless the progressive result of growth under circumstances not permitting the normal spread and play of each hoof upon the ground.

This monstrosity is clearly a freak in an individual case, belonging to the general category of web-fingering; and it is not to be compared with the more profound modifications of the pig's foot which I describe in the succeeding article. Its occurrence is so obviously and seriously disadvantageous that it could scarcely be perpetuated to any extent.

ART. XIII.-ON A BREED OF SOLID-HOOFED PIGS APPARENTLY

ESTABLISHED IN TEXAS.

BY DR. ELLIOTT COUES, U. S. A.

My attention has recently been called to this matter by communications from a valued correspondent, Mr. G. W. Maruock, of Helotes, Bexar County, Texas, who has further laid me under obligations by transmitting the well-prepared specimen from which the accompanying illustration has been made.

Like the monstrosity of cleft-hoof occasionally witnessed in the horse or ass, the peculiarity of the solid hoof is already known to occur in the domestic pig. Thus, I am informed by Professor Baird of his recollection of such a case, there having been many years ago a number of solidhoofed pigs in the possession of a person residing near Carlisle, Pa., who specially valued them for some advantage which the peculiarity was supposed to confer. Professor Leidy also tells me that the same thing is within his knowledge.

As in the case of the monstrosity of cyclopism, which is of compara tively frequent occurrence in these animals, however, the formation of the solid hoof seems to have been regarded as a mere freak of nature, or monstrosity in the usual sense of that term; whereas I gather from my correspondence with Mr. Marnock that the solid hoofed pigs of Texas are established as a race which transmits its peculiarities to its offspring as surely as it does any other portion of its structure. I should judge from Mr. Marnock's remarks that the solid-hoofed pigs of his locality constitute a large proportion, if not a majority, of the species.

The peculiarity is so firmly established that no tendency to revert to the original and normal form is observable in these pigs. Mr. Marnock informs me that the cross of a solid-hoofed boar with a sow of the ordinary type produces a litter the majority of which show the peculiarity of the male parent.

He alludes to a popular belief which ascribes the origin of this breed to crossing with the peccary,-this being of course fallacious.

The upshot of this modification of the foot is that a strictly artiodactyle animal is transformed into an imperfectly perissodactyle one. As far as the hoof itself is concerned, the pig is completely solidungulate. It is also perfectly "odd-toed", or single-toed, in the terminal phalanges, anchylosis of which produces a single broad phalanx in the axis of the limb. Above this, however, the other two phalanges, medial and proximal, of each of the two principal lateral digits, remain perfectly dis

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tinct, and, moreover, widely separated from each other by intervention of a special ossicle, doubtless a sesamoid, in the axis of the foot immediately above the single terminal phalanx.

The actual structure, both of the bones of the digits and of the horny hoof, will be appreciated from a glance at the accompanying figure. This is engraved of life size, front view, with the hoof withdrawn sufficiently to display all the parts. The preparation is from a young subject about three months old, in which the proximal epiphyses of the phalanges are still evident. The pair of distinct proximal phalanges of normal characters, or nearly so, are seen to be succeeded by nodular medial phalanges, which latter, as well as the distal extremities of the proximal phalanges, are widely separated by intervention of a special ossicle in the axis of the foot. To these succeeds a single broad and flattened terminal phalanx, obviously composed of the pair of distal phalanges auchylosed together. In this specimen, the ancbylosis is complete, even at so early an age of the subject; its condition apparently being not the result of progressive confluence of the two bones, but of their original connation.

The terminal phalanx is flattened and somewhat scooped out on its posterior aspect, without trace of previous separation into halves. In front, however, as shown by the figure, it presents a central triangular elevation, apex downward, and base articulated with the nodular ossicle above it, as if a wedge of bone had been thrust into the axis of the limb between the primitive distal phalanges. This wedgeshaped piece of bone is completely anchylosed with the present single distal phalanx; and below its apex the edge of the bone is perfectly continuous across the axis of the foot.

The central nodular ossicle, which I have already mentioned as a sesa. moid, articulates with all five of the bones of the foot. I cannot account for its presence unless it be a displaced sesamoid, such as for example that which is normal beneath the base of the distal phalanx of the horse, and known to some as the "os subarticulatum". In the normal pig's foot, there are several pairs of sesamoids beneath the phalangeal articulations; and the bone in question may be regarded as a confluence of the pair at the base of the distal phalanges, or of two pairs at the bases of the medial and distal phalanges respectively. The displacement of these sesamoids brings the ossicle into position in the axis of the foot between instead of under the bones. Or, it may be that this ossicle is a confluent pair of sesamoids from beneath the basis of the medial phalanges, and that the wedge-shaped piece of bone which appears upon the front of the distal phalanx, consolidated therewith, represents sesamoids from beneath the distal phalanges.

The horny hoof encases these bones as far as the distal extremities

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