294 ANNUAL RECOKD OF SCIENCE AND INDUSTRY. 



in lime-water or a solution of gypsum. 6 C,Jtdy 14,1870, 



282. 



PITH OF WOODY MATTER. 



Mr. A. Gres, in a recent memoir upon the pith of woody 

 plants, endeavors to show that this pith, in the dicotyledon- 

 ous species, is not simple and uniform in its organization, as 

 has been supposed, but that it is capable of furnishing appre- 

 ciable characteristics for a natural classification. He finds 

 that it preserves its vitality for many years, sometimes even 

 to a very advanced age, and that it contains in one part or 

 other of its cellules a supply of nutritive material in the form 

 of starch and tannin, which is taken up again at the moment 

 of the development of the new verdure in spring. He thinks, 

 also, that it participates with some of the tissues of the wood 

 itself in the nutrition of the plant, and that it fills an impor- 

 tant physiological place, being far from drying up after the 

 second year, and thus becoming subsequently only a dead 

 tissue. 37?, xxv., August 10, 181. 



FERTILIZATION OF THE FLOWERS OF RHODEA. 



The structure of the flowers of Hhodea japonica is such 

 that fertilization can only take place when the calyx has been 

 gnawed through in some way during the period of blooming. 

 This is accomplished usually by snails, which habitually in- 

 fest the plant. These creep out along the spathes and gnaw 

 the calyx without injuring the ovary. The mutual relation- 

 ship between this plant and snails is so close that the culti- 

 vation of the one has even been suggested as a means of se- 

 curing the destruction of the other in a garden, since wher- 

 ever planted it is sure to be sought out by the snails, which 

 accumulate in quantities upon it, and are readily captured. 

 1 6 r , 1870,578. 



SORBY OX TINTS OF AUTUMNAL FOLIAGE. 



In an elaborate article by Mr. Sorby upon the varied tints 

 of autumnal foliage in the Quarterly Journal of Science, he 

 comes to the conclusion that the production of the fine tints 

 of autumn is an evidence of diminished vital powers of the 

 plants. This generalization also agrees with the fact that 

 the unhealthy branches of a tree turn yellow, while the rest 



