PROCEEDINGS OF SOCIETIES. 131 



A specimen of a curious excrescence from the bark of a Camellia, sent by Mr. 

 MUls, of Enys Gardens, Penrjn, was then shown. The excrescence had much 

 of the aspect of a Polyporus, but seemed to be an excrescence from the bark, 

 ivom which it was with difficulty separated. In one case two branches had 

 become united together, and the point of union was covered with this shell-like 

 excrescence. None of the members of the committee, nor any of the Camellia- 

 growers present at. the general meeting, had ever seen anything similar. Tlie 

 only suggestion was that the adventitious growth was the result of some injury 

 to the plant. Dr. Masters undertook to submit the growth to microscopic 

 examination, and report more fully at a future meeting ; as also on a curious 

 specimen resembling the " burrs" seen on Birch-trees, but in this case stated 

 to be formed on the roots of a Currant-bush. Dr. Masters further reported 

 as follows on the Bridgesla spicata exhibited at the last meeting : — " The 

 peculiar out-growths of this plant are protruded from the young shoots above 

 the axils of the leaves, and above the branch proceeding therefrom. In the 

 fully developed state they are about the size of a large pea, of a yellowish colom', 

 and have a genei-al resemblance to the tufts of hairs found in similar situations 

 in Pereskia. In the youngest condition the excrescences occur in the form of 

 small, smooth, conical projections, covered with an outer layer of small oblong 

 cells, the outer walls of which are thickened ; subjacent to these are four or 

 five rows of small, splieroidal, densely-packed cells, also cortical in their nature. 

 These overlie a mass of ordinary cellular tissue, the cells of which contain chlo- 

 rophyll. Running into this conical cellular projection are two rows of small 

 spiral vessels, which converge towards the apex of the cone, and form a loop. 

 These spiral vessels are continuous with those of the vascular circle of the 

 branch, and are surrounded on all sides by oblong, thui-walled cells, whose 

 long diameter is parallel to that of the spiral vessels, and more or less at right 

 angles to the direction of the parenchymatous tissue of the cortex and also of 

 the meduUa. The constituent cells of the medulla are spheroidal, and destitute 

 of chlorophyll. Here and there spu-al vessels traverse the medulla, quite iso- 

 lated from the general vascular circle. In tlie more fully developed excrescences 

 the appearances are similar, except that the outer epidermal cells now show 

 themselves in the form of long cylindrical cells (hairs), some of which are club- 

 shaped at the extremity. Some of these hairs appear to be unicellular, while 

 others show one or two transverse partitions. The hairs in questiou are rather 

 thick- walled, and contain a few scattered small highly refracting granules 

 (starch?), resembling the granules found in autumn when the leaves have 

 assumed their autumnal tints in consequence of the decay of the chlorophyll. 

 From these appearances the inference seemed to be, that the growths in questiou 

 were of the nature of adventitious roots covered by hypertroj^hied epidermal 

 hairs." An Arum from Chiswick, with an adventitious leaf attached to the 

 spadix, and wliite, like the spathc, was then shown. A similar illustration was 

 forwarded some time since by Mr. D. T. Fish. 



Geological Society op London. — March dth, 1870. — Warington W. 

 Smyth, Esq., F.R.S., Vice-President, in the chair. The following commuui- 



