Page:Quarterly Journal of the Geological Society of London, vol. 26.djvu/768

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part. The ribs (e, e, e) are divided in the same direction ; but they for the most part are torn asunder, as the division has not extended much beyond the backbone. The same may be said of the head (b, c, d), which lies split open horizontally below the ventral margin of the animal. The neck (a') is curled round in front of the anterior end of the body in the direction of the head, which lies in a reversed position, as we have just seen, below the trunk, which to some little extent overlaps it. The tail or posterior end of the spine seems to have been turned round the hinder extremity towards the same region, but none of its bones are present ; only an indistinct depression indicates the fact.

As the body lies thus curled up, it measures 15 inches in length ; and in width, from the backbone to the distal extremity of the ribs, 8 inches. The length of the specimen, including the head if stretched out, would be about 35 inches.

The course of the backbone is obvious enough, running along the dorsal margin, turning round in front of the body, and curving back- wards in the direction of the occipital region of the skull ; but, unfortunately, at this point the slab is broken away for upwards of 2 inches, separating by that space the head from the spine. The vertebral column (a), as seen in longitudinal section, is about an inch and one-eighth wide ; but it is quite impossible to make out any of the characters of the vertebrae, or even to determine their dimensions with the necessary precision. All that can be said on this point is that, from the assumed extent of four consecutive vertebrae, the length of a single vertebra may be estimated at about seven- eighths of an inch. This difficulty arises partly from the crystalline condition of the whole line of the vertebrae, and partly from the fact that the whole of the bone is broken up and partially removed, little else than cellular or flaky matter remaining, all boundaries determining the forms of the parts having disappeared.

There is, however, one feature of the vertebral column which cannot pass unnoticed. The neck (a') seems to have been remarkably long for a Labyrinthodont. From the length of the ribs, the body must undoubtedly have been of considerable depth ; and unless the neck had been long, it is evident that the head, if attached to the trunk, as it appears to have been when deposited, could not have assumed the position in which it is placed immediately below and parallel to the belly. But it is impossible to determine the exact length of this portion of the column, as we cannot be sure how many of the anterior ribs are wanting.

The ribs (e, e, e) are arranged in regular order, inclining from before backwards ; but have been apparently torn bodily from their spinal attachment by pressure after deposition, and now their proximal extremities are removed about an inch and a quarter from the column, the whole having been afterwards pushed downwards. Twenty-one are distinctly displayed in parallel order, about a quarter of an inch apart from each other in front ; but the space dividing the posterior ones is somewhat greater. They are inclined diagonally from the front in slightly arched curves, the concavity being forward ; and traces of eight or ten more can be determined, so that in all there