ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 597 



BOTANY. 



A. GENERAL, including- the Anatomy and Physiology 

 of the Phanerogamia. 



a. Anatomy. 

 (1) Cell-Structure and Protoplasm. 



Alleged Occurrence of living Protoplasm in the Air-passages of 

 Water-plants.* — Observations made by Herr L. Kny on various water- 

 plants throw considerable doubt on the statement made by several 

 observers, especially Baranetzki and Sauvageau, that the air-passages in 

 the tissues of water-plants are clothed with a layer of living protoplasm. 

 He found no certain evidence of such a layer — whether containing nuclei 

 and chromatophores or not — which could not have arisen from the flow 

 of intracellular protoplasm from adjoining cells. 



(2) Other Cell-contents (including: Secretions). 



Chemistry of Chlorophyll.f — Dr. L. Marchlewski and Herr 0. A. 

 Schunk state that crude leaf-extracts contain two green colouring matters, 

 chlorophyll proper and another, which is present only in small quantity 

 and which exhibits a red fluorescence. They describe a method by 

 which true chlorophyll can be obtained almost free from this green 

 colouring matter. Hartley's " yellow chlorophyll " is a mixture of a 

 green colouriug matter, which is not chlorophyll, with members of the 

 xanthophyll group. When isolated, its colour is green, and the term 

 " yellow chlorophyll " is therefore not applicable to it. 



Latex and its Functions.:); — Mr. J. Parkin notes the following points 

 in the latex-producing trees and shrubs of Ceylon. The coagulation of 

 the latex of Hevea brasiliensis suggests that the proteid is rather an 

 albuminate than albumen. A proteid is also present in the latex of 

 Gastilloa elastica and C. Marlchamiana. The latex of Castilloa and that 

 of the capsule (but not of the trunk) of Hevea darkens on exposure to 

 the air, indicating the presence of an oxydase. Although laticiferous 

 tubes contain both starch and sugar, the starch (especially the starch- 

 rods of the Euphorbiaceas) appears to have no nutritive value, and to have 

 nothing to do directly with carbon-assimilation. There is frequently a 

 considerable difference in the properties of the latex from young and old 

 organs of the same plant. The author suggests that one of the most 

 important functions of a laticiferous system may be that of holding 

 water in reserve. 



Poisonous Property of Raphides.§ — Herr L. Lewin points out that 

 the general theory that crystals of calcium oxalate in the tissues of 

 plants serve to protect them against the attacks of animals, is con- 

 tradicted by the fact that some of these plants are edible by man, while 

 many are eagerly eaten by animals of all kinds. The mechanical injury 

 which has been attributed to them is also not supported by facts. The 



* Ber. Deutsch. Bot. Ges., xviii. (1900) pp. 43-7. 

 t Proc. Chem. Soc, xvi. (1900) pp. 148-9. 

 X Ann. of Bot., xiv. (1900) pp. 193-214 (1 pi.). 

 § Ber. Deutsch. Bot. Ges., xviii. (1900) pp. 53-72. 



