428 SUMMARY OF CURRENT RESEARCHES RELATING TO 



Nature of the Vegetable Alkaloids. * — From experiments made 

 •chiefly on Cojfea arabica and liberica, the seeds of which contain a large 

 quantity of caffeine, the late G. Clautriau concludes that no diminution 

 in the amount of the alkaloid takes place during germination, whether 

 grown in the dark or in the light ; the young plant contained more 

 caffeine than was present in the endosperm. The author regards the 

 alkaloids generally as excretory products of metastasis, which may, 

 under certain circumstances, he used up again in further constructive 

 metastasis. 



Starch in Evergreen Leaves.f — According to K. Miyake, the amount 

 of starch in evergreen leaves at any one period of the year differs greatly 

 in different plants. As a general rule, those of Monocotyledons contain 

 less than those of Dicotyledons, Gymnosperms, and Pteridophytes. The 

 minimum is about the end of January (in Japan) ; after the end of 

 February the amount again increases. In Central and Southern Japan 

 many evergreen plants contain some starch in the chlorophyll-bodies 

 during the coldest period of winter, while in Northern Japan it usually 

 disappears at that time from the mesophyll and the guard-cells of the 

 stomates. Although the process is comparatively feeble, assimilation 

 and the transport of starch do take place during the winter. 



Protopine-bearing Plant.} — In Adlumia cirrhosa, a climbing plant 

 belonging to the Fumariacese, J. O. Schlotterbeck finds the roots to 

 contain a small quantity of this alkaloid, which is probably identical 

 with furaarine ; this latter, being the earlier name, should be retained. 

 The author states that this alkaloid occurs in a larger number of species 

 of plants than any other alkaloid, all belonging to the Papaveraceas or 

 FumariaceaB. 



Glucoside present during Germination in the Beech.§ — In the young 

 beech seedling P. Tailleur finds a glucoside and a diastase which in the 

 presence of water, give rise to methyl-salicylic acid, with its character- 

 istic odour of winter-green, and to glucose which is assimilated by the 

 plant. This reaction is localised in the hypocotyl ; it does not occur in 

 the seed nor in the mature jjlant. 



Reserve Carbohydrate producing Mannose.|; — J. Parkin finds, in 

 the bulbs of IAlium eandidum, and other species of the genus, a carbo- 

 hydrate which on hydrolysis yields mannose and not glucose. The 

 author believes it to be widely distributed in the vegetable kingdom. 



(3) Structure of Tissues. 



Peculiarities in the Cambium of Trees.lf — L. Jost finds that, in 

 pine-trees, the cambium undergoes a change at the point of departure 

 of a branch from the main stem, the cells becoming shorter and thicker ; 

 this can be especially observed in the medullary rays. The same is the 



* Ann. Soc. r. d. Sci. Nat. Bruxelles, ix. (1900) 113 pp. See Bot. Zt<r., lix. 

 (1901) 2 t0 Abt., p. 70. 



t Bot. Mag. Tokyo, xiv. (1900) p. 44. See Bot. Centralbl., lxxxv. (1901) p. 3S5. 



t Anacr. Chem. Journ., xxiv. (1900) pp. 249-53. 



§ Comptes Kendus, cxxxii. (1901) pp. 1235-7. 



|| Proo. Cambridge Phil. Soc. xi. (1901) pp. 139-42. 



% Bot. Ztg., lix. (1901) 1" Abt., pp. 1-24 (1 pi. and 6 figs.). 



