282 
PLESIOSAURUS 
The vertebras agree with those from the Lias, and 
certainly belong to the Plesiosaurus dolichodeirus. 
Among the bones which we are unable to assign 
to any known recent or fossil animal, is a humerus, 
which, from its shortness, thickness, and the ex- 
treme width of its cubital articulation, would ap- 
pear to be adapted for swimming. It bears a 
greater analogy to the humeri of the cetacea than 
to those of the lizards : Dr. Buckland referred it 
to the whale ; but there are essential differences 
between the humerus of the latter and this fossil.* * 
It does not correspond with the humeri of the 
known plesiosauri ; yet it may possibly belong to 
tebrae ; the back of 27, and the tail of 28 ; making a total of 90. The 
head is so small, that its length is not more than a fifth part of that 
of the neck. 
* M. Cuvier, to whom this opinion was communicated, obliged us 
with the following observations on the subject: — 
“ Quant aux ossemens que vous croyez etre de cetaccs, ils meritent 
certainement d’etre etudies avec attention, car ce serait la premiere 
fois que Ton trouverait des ossemens de ces mammifcres dans les 
formations situees au-dessous de la craie. Mais il y a des vertebres de 
grands reptiles, qui ressemblent si fort a celles de certains dauphins, 
qu’il est facile de s’y tromper ; toujours faudrait-il examiner leur position 
avec beacoup de soin, et voir s’il n’y aiirait point a cet egard de dif- 
ference entre ces os de cetaces et ceux de reptiles. Rien n’empcche- 
rait, ce me semble, que dans les couches de sables que se trouvaient 
former la surface du sol, la mer ne soit venue, dans ses nouvelles irrup- 
tions, apporter des depouilles nouvelles, et les confondre avec les 
anciennes ; mais je pense que soit dans leur position, soit dans leur 
etat physique, on trouvera des differences characteristiques de I’epoque 
a laquelle ces depouilles ont et^ enfouies.” 
From these remarks of this illustrious philosopher, we have hesitated 
to refer the fossils in question to the cetacea, until the discovery of 
more illustrative specimens shall establish or refute their supposed 
analogy, since of their geological habitat there cannot be the slightest 
doubt : it is probable they will hereafter be proved to belong to some 
of the saurian reptiles of the Wcalden. 
