tuted as completely to perform the offices allotted to them in the rank 

 wh.ich they hold in the scale of creation. 



This wonderful and close analogy also offers to our admiration a 

 plain demonstration, not merely of the power and of the wisdom of our 

 great Creator, but of the rich infinity of resources from which he has 

 been enabled to diversify his works. But to return to the animal, the 

 examination of which led to these reflections. It differs from the alcy- 

 onia already described, in having no particular cavity for the recep- 

 tion of the sea water. We are, however, fully authorised in consider- 

 ing this and all the rest of thi sseries not merely as sponges, since 

 they possess, beside the spongy parts, a more complicated apparatus 

 for procuring the reception and ejection of the sea water, the vehi- 

 cle of their food. 



In this particular animal, an admirable contrivance appears to have 

 been employed for the performance of this function. In the alcyonia 

 already described it was remarked, that at their superior parts an 

 opening was always to be found, and from the sea water received 

 in this cavity, bearing an analogy with the stomach of the more per- 

 fect animals, the necessary portion of nutriment was supposed to have 

 been derived. But in this body no particular cavity seems to have ex- 

 isted : the sea water imbibed by the spongy substance of which this 

 animal body was composed, was most probably ejected by the con- 

 traction of that body, aided by the additional compression derived 

 from the contractions of those filaments, which we see pass through its 

 substance and over its surface ; and which, probably possessing the pro- 

 perties of a muscle, would occasion a regular alternate contraction and 

 dilatation of the cavities, by which a perpetual renewal of its matter 

 of nourishment would be obtained. 



I am, unfortunately, unable to speak positively respecting the place 

 where this fossil was found : I have, however, great reason to suppose, 

 it was obtained from some of the gravel pits in this island. 



The fossil depicted Plate IX. Fig. 11 and Fig. 1.3, evidently belongs 



