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interspersed with vertical pillars, or were there in some one direction two or 

 three cavities, of which the drawings showed sections ? Did he observe 

 any connection between these cavities and the oscnla ? 



Mr. Priest said that the Sponge having been in spmt much of it was 

 hardened, but apart from that it appeared in its natural condition. The 

 section was made through the walls of the Sponge, and had the appearance 

 of arches, as shown in the diagram. In one of the slides the cavity could 

 be traced from the centre up to the oscula, where the water passed out. 



Mr. Buffham wanted to know whether there were a number of vertical 

 pillars dotted about the whole base of the Sponge, and running up to its 

 roof, or whether there were three principal cavities through which the 

 diagram showed a section ? 



Mr. Priest said the openings seemed to be all over the Sponge, the pillars 

 supporting the outer crust. 



The President enquired if they were pillars supporting the roof, or the 

 wall of the channels ? 



Mr. Buff ham said supposing they began at the base, was the whole space 

 divided into numerous channels, or were there three principal ones running 

 right through ? He should gather that there were a number of cavities 

 communicating with each other all over the Sponge. 



Dr. Matthews asked if they were cavities or channels ? 



Mr. Priest, in reply, said that they were channels, and had the appearance 

 shown only in section. 



A vote of thanks to Mr. Priest for his paper was unanimously carried. 



Mr. W. H. Gilburt said that some little time ago Dr. Cooke called his 

 attention to some leaves of a species of Bomaria which he had found in 

 Kew Gardens. These plants belonged to the same order as the Snowdrop, 

 but differed in appearance from the British members of the order, the 

 Bomarias being climbers. The special point about them which called for 

 remark was that the whole structure was reversed — what should be at the 

 top being found near the bottom surface of the leaves, and vice versa. In 

 an ordinary leaf— say of Aucuba or Laurel — they would find on the upper 

 surface a well developed cuticle, and beneath that a layer of flattened cells, 

 sometimes containing chlorophyl ; then came another layer of cells 

 arranged with their greatest length at right angles to the surface of leaf, 

 and then a quantity of more or less branched cells, and immediately under 

 that came the lower epidermis containing the stomata. On the upper 

 surfaces of leaves stomata were comparatively rare, except in the case of 

 such as grew vertically, like the Hyacinth ; but in the instance before them 

 they had a leaf in which the lower surface was a true cuticle without 

 stomata, the order of the arrangement of the cells was reversed throughout, 

 and the upper surface contained stomata in abundance ; and remembering 

 the functions of the vaxuous parts of the leaf and the provision made by 

 nature for protecting the stomata from dust, &c., this reversal of the usual 

 order of things was very remarkable. So far as ho knew it had never 

 been observed before. Dr. Cooke had made enquiries of Mr. Baker, one of 

 our best authorities on the order ; but he know of no one having previously 

 observed it. The leaves are developed normally in the bud, but as soon 



