On the difference in the mode of ossification of the first and other metacarpal and metatarsal bones / by Allen Thomson.

  • Thomson, Allen, 1809-1884.
Date:
[1868?]
Catalogue details

Licence: Public Domain Mark

Credit: On the difference in the mode of ossification of the first and other metacarpal and metatarsal bones / by Allen Thomson. Source: Wellcome Collection.

Provider: This material has been provided by The University of Glasgow Library. The original may be consulted at The University of Glasgow Library.

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    separating epiphyses on the proximal ends of the second and third bones of the series, and less obviously of the fourth and fifth bones. In the foot, however, I found the groove on the fifth metatarsal bone more distinct than that on the corre- sponding metacarpal. In a skeleton of the echidna histrix in my possession, and which appears to be full grown, although there are still marks of epiphyses in the larger bones of the limbs, ossification hits proceeded so far in the bones of the foot as to prevent me from determining the position of the epiphyses'. I have examined two skeletons of the common seal, one somewhat more advanced in growth than the other, h^t both young, and with the ossification proceeding in the shaft and extremities in such a way as to present appearances peculiarly favourable for distinct observation. One of these skeletons had been macerated and dried; the other was in the wet state. The state of the parts was essentially the same in both, and is represented in so far as it appeared unusual in figure 5, I and II, taken from the wet specimen. In the fore-limbs the mode of ossification did not differ m any respect from that which is considered most usual m man, there being only distal epiphyses in four metacarpal bones, and only proximal epiphyses in the first metacarpal and in all the digital phalanges. But in the hind-foot it was very different; for there the first metatarsal bone, besides the usual proxinuu epiphysis as in the metacarpal bone, presented a large and dis- tinct distal epiphysis, precisely similar to those of the four other metatarsal bones which had only distal and no proximal epiphyses. Further, all the phalanges of the hind-foot, except the terminal ones, presented, in addition to the usual proximal 1 I may remark here that in smaU mammals, and m birds and is some risk of being misled as to elevation a small groove, sometimes accompanied on tlie laminar corresponding place in other Mimals that, S ^ epiphysis from plate of cartilage proceeds, which for a to LterLne the the end of the shaft. In all cases of doubt it is desirabie^^^^ existence of epiphyses by longitudinal sections thro g