416 Rev. W. Buck land on the Paramoudra, and 



their lower extremity. It is possible the Paramoudra, having a tube 

 with two apertures, may have possessed a character intermediate 

 between a gigantic spunge and an ascidia. I have broken very 

 many of these fossils in search of internal organization, and in 

 one case only found the appearance represented in PI. 24. No. 7, 

 and there magnified beyond its natural size. It presents a small 

 cluster of hexagonal cells about is of an inch in diameter. The 

 substance of the septa dividing the cells does not exceed in thick- 

 ness that of the finest paper, and appears to be silex much iron- 

 shot ; the cells are filled with silex of the same colour with the 

 mass that envelopes them, and display no traces of radii or fibres 

 traversing their interior. This small cluster of cells was decidedly 

 inclosed in the body, and within the crust of a Paramoudra, extend- 

 ing inwards, not an inch from the epidermis. As this is the only 

 specimen in which I have seen or heard of such traces, 1 think it 

 more probable that they are a fragment of some extraneous body, 

 that was accidentally attached to, and at length inclosed within the 

 substance of the Paramoudra, than that the traces of an organiza- 

 tion so distinct and decided, if it had ever existed generally, should 

 have been so totally destroyed in every other specimen that has 

 been examined, as to leave only the outward form to guide us 

 in our conjectures as to the character and habits of the original 

 animal. 



The mineral history of the Paramoudra seems intimately connected 

 with that of many other spungiform bodies which we find in chalk 

 flints. In all these cases the organic bodies thus preserved, appear 

 to have been lodged in the matter of the rock, while it was in the 

 state of a compound, unconsolidated, pulpy fluid ; and before that 

 separation of its siliceous from its calcareous ingredients, which 

 has given origin to the flinty nodules in chalk, and to beds and 



