118 
ment a part of this surface is shewn, Plate XL Fig. a. Another section 
was then made across the inferior part, where it began to terminate 
conically, and here also the lens made an exactly similar structure 
appear. Having thus obtained two transverse sections of these tubes, 
I expected, by obtaining a section in the direction of the sides of the 
fossil, to procure a longitudinal section of these tubes, but I was surprised 
to find, after the necessary operations, that the appearance yielded by 
this surface was exactly similar with that of the two former ; it seeming 
that these tubes or vessels had their openings, in the same manner, on 
every part of the surface. 
The examination of the structure of the several fossil alcyonia, 
which have preceded the present, has shewn that it has been such in 
all as was best calculated to furnish the inhabitants of these substances 
with an abundant renewal of sea-water, fraught with the animalculse 
or other matters, which would afford them nourishment. A very slight 
degree of consideration will be sufficient to discover that the form and 
structure of the present fossil is such as would accomplish this 
purpose in a manner the most complete. The whole surface, we see, 
is covered with the minute openings of tubuh, of which the substance is 
formed; and these are connected in fasciculi, which, being disposed 
in a radiated form, round the large ventricular opening, might, in the 
original alcyonium, by a pulsatile action, a regular systole and diastole, 
have procured a rapid succession of sea-water, teeming with the 
proper nutritious matters ; the water received in the ventricular cavity 
being thus expelled by the vessels opening all over the surface. The 
substance of this fossil appears to be lime, argil, and silex, in intimate 
combination. 
The account of this fossil, given by Mr. Walch, in Knorr's work, is 
very short. He merely thus describes it in the words of M. D’An- 
none : — “ Ce fongite est a peu pres de la forme d’un hemisphere ; 
du sommet partent des sillons separ6s par des rides saillantes ou des 
lames epaisses, qui descendent a la circumffirence de la partie platte 
