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ment. A part of this surface is shewn, Plate XI. Fig. a. Another 

 section was then made across the inferior part, where it began to ter- 

 minate conically, and here also the lens made an exactly similar struc- 

 ture 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 appear- 

 ance 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 animalculae 

 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 pur- 

 pose, in a manner the most complete. The whole surface, we see, is 

 covered with the minute openings of tubuli, 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 dias- 

 tole, have procured a rapid succession of sea water, teemirig 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 separes par des rides saillantes ou des 

 lames epaisses, qui descendent a la circumference de la partie platte 



