$Id: Mantell1850-plate-XXIII.notes,v 1.2 2009-03-09 10:51:45 mike Exp $

From Mantell (1850: 3823) (PDF page 5):

	Distal caudal vertebra, Plate XIII. fig. 11.--In referring the
	unique caudal here figured to the same category as the
	preceding, I offer the suggestion only as probable.  The
	centrum is of a subcylindrical form, 4+1/2 inches long, and
	slightly convave on both facets.  The most remarkable featuire
	in the this bone is tje anchylosis or rather confluence of the
	heads of the chevron bone with the body (Plate XXXII. fig. 11
	j,j), a character common in fishes, but which, I believe, is
	unknown in reptiles, save in one genus, the fossil animal of
	Maestricht, the Mosasaurus, whose occurrence in the English
	chalk was first ascertained in 1820, by my discovery of two
	convaco-convex caduals with confluent chevron bones.  The
	remarks of the illustrious Cuvier on the caudal vertbrae of
	the Mosasaurus, are in every respect applicable to the
	specimen under consideration.  After metioning the median
	caudals as having "à leur face inférieure deux petites
	facettes pour porter l'os en chevron," he decribes the more
	distal series which form a great part of the tail; in these
	"l'os en chevron n'y est plus articulé, mais sondé, et fait
	corps avec elles."

	The structure of the spinal column of the Mosasaurus therefore
	proves that vertebrae having the chevron bone articulated by
	who distinct facets 9as Plate XXII. fig. 8), may be followed,
	in a more distal part of the caudal region, by a series with
	the haemapophysis anchylosed to the centrum (as in Plate
	XIII. fig. 11).

The Cuvier quotations translate as: "on their inferior face, two small
wear facets for the chevron bone" and "the chevron bone is no longer
articulated, but ?drilled, and the body with them".

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From Mantell (1850: 389) (PDF page 17):

	PLATE XXIII.
	[...]
	Fig. 11 A caudal vertebra with the chevron bone anchylosed to
	the body, as in the distal caudals of the Mosasaurus.
	11a. Lateral view.
	11b. View of the inferior surface.

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