Proceedings of the British Association. 125 



lime was soluble in muriatic acid, from which, by evaporation, it 

 could be obtained in crystals. He had tried experiments with 

 phosphorite as a manure without any appreciable advantage. — Mr. 

 Solly stated, that in some experiments on the comparative advantages 

 between the phosphorite and the phosphate of lime in bone, the 

 superiority was decidedly on the side of the phosphorite, which was 

 applied in the state of fine powder, mixed with the soil. He then 

 suggested for inquiry, whether fluorine might not be formed by the 

 plants themselves. — Prof. Graham remarked that fluorine could not 

 be detected in the ashes of plants. He considered that the fluorine 

 in bone was derived from water. — Dr. Carpenter made some remarks 

 on the differences observed under the microscope in the molecular 

 structure of the phosphorite and the phosphate of lime in bone. 



'The Influence of light on the germination of seeds and the 

 growth of plants,' by Mr. R. Hunt. — The author postponed a full 

 report on this subject until he had been enabled by the experiments 

 of another year to reconcile, if possible, some very anomalous results. 

 Several experiments were described, all of which went to confirm the 

 statement originally made by Mr. Hunt that light prevented health- 

 ful germination, and was detrimental to the growth of the young 

 plant. The author now gave the results of some experiments made 

 with a view of determining the question of the production of the 

 woody fibre. He finds that plants growing under the influence of 

 light which has permeated blue aud red media, contains more water 

 than those which had been grown under the influence of rays which 

 had permeated yellow and green absorptive media. On the contrary, 

 the formation of woody fibre is greatest in the plants grown under 

 the yellow and green relatively as follows : — 



Those under the blue leaving 7.16 per cent, of woody fibre. 



the red 7.25 



the green 7.60 



the yellow 7.69 



Young plants in a healthy state were removed from the garden to the 

 influence of the isolated rays. In all cases, the plants died under the 

 yellow light in a few days; they slowly perished under the influence 

 of the green, and only grew healthfully under the red and blue 

 light. 



