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contrary to make him pause before confirming the opinion so strongly expressed 



by the reader of the paper "that a boring sponge was a creature of the im- ^ 



agination." It might be interesting to mention that the work of destruction ^~ 

 upon the shell of the oyster was carried on so rapidly, and to such an extent, 

 that one owner of oyster beds believed he had lost from this cause alone this 

 year at least £400. It was quite correct, that when infested by the sponge the 

 oyster thickens up its shell rapidly from the inside, apparently to keep out the 

 intruder. He regretted that he was not aware that the subject was to have been 

 brought forward, or he would have brought with him to the meeting some speci- 

 mens in illustration of his remarks. 



Mr. Waller pointed out that he had, upon his diagram, represented a portion 

 of a shell, with the holes shown between the laminae. 



Mr. Henry Lee said that the portions of the laminae to which he had referred »<;_ 

 were not the same as those drawn — they had the appearance of being eroded, as 

 if acid had been poured upon the part. 



Mr. Waller said that Dr. Bowerbank had found a Pecten (?) in a cavity 

 entirely filled with the shell ; and Mr. Handcock disbelieved that there was any 

 action of a cutting nature- 

 Mr. Henry Lee said he was quite of the same opinion. 



Mr. Charles Stewart said, that although he was not a member of the Club, he 

 hoped he should not be considered out of order in drawing attention to one par- 

 ticular relating to the C'liona, which had not been mentioned by Mr. Waller. 

 This was the way in which it appeared when fully expanded in undisturbed 

 water. He then drew a diagram upon the black board, and explained that 

 when entirely undisturbed the sponge might be seen protruded from the stone 

 or shell as mushroom-shaped elevations, having a superficial resemblance to a 

 Zoanthus. increased by radiating lines on their upper surface. Besides these, 

 which were by far the most numerous, there were a few conical elevations of a 

 larger size, and having a large opening (osculum) on their summits. By a little 

 careful examination, it would be found that the upper surface of these mush- 

 room-shaped processes is the only part perforated by the small pores through 

 which the water passes into the interior of the sponge, as shown by the small 

 particles of mud and other substances which were drawn towards them. He 

 agreed with Mr. Lee in believing that there was evidence in the peculiar cha- ^ 

 racter of the perforations in support of the idea that these sponges really did 

 make the holes, although it was not quite clear by what means. Many of the 

 Annelids no doubt secreted an acid, and he had obtained from them an acid re- 

 action upon litmus paper, but there appeared to be no such re-action produced ^—- 

 by the Cliona. 



Mr. Waller asked how they were to account for the perforations in shells such 

 as he had sometimes found, which were so entirely perforated that he could break 

 it up between his fingers ? 



Mr. Charles Stewart imagined that these must be quite old shells. 



Mr. Henry Lee said that the sponge was very readily destroyed by drying, 

 and it had been found by experiments that by laying out the oysters upon the ^—* 

 sand, the sponge was destroyed much more easily than the oyster, and this 

 means had been resorted to for getting rid of the sponge. 



The President said that he could not pass on to the next business of the 

 meeting without thanking those gentlemen who had so ably referred to the 

 subject before them, and who, in doing so, had contributed so much interesting 

 information. With reference to the means by which the sponge worked, he 



