608 SUMMARY OF CURRENT RESEARCHES RELATING TO 



through the ordinary stomates, but through stomates of special con- 

 struction which are found chiefly at the meeting-points of the veins. 

 The residue obtained by the evaporation of the drops contains calcium 

 carbonate and potassium carbonate, the latter of which salts attracts 

 water eagerly. In Boehmeria the water escapes through fissures in a 

 small papilla composed entirely of epidermal cells. It is a process of 



simple filtration. 



(3) Irritability. 



Geotropism of the Hypocotyl of Cucurbita * — According to Mr. E. 

 B. Copeland, Cucurbita displays the geotropic response without direct 

 regard to the consequences, and without the power of adaptation to un- 

 usual conditions. The rapid growth of the under side of a prostrate 

 hypocotyl carries the cotyledons upward ; but if a young plant be placed 

 horizontal with the cotyledons fast and the roots free, the same response 

 bears the roots upwards, and is therefore likely to be immediately fatal. 



(4) Chemical Changes (including Respiration 

 and Fermentation). 



First Organisation-Product of Phosphoric Acid.f — Dr. S. Posternak 

 has found in seeds a phosphor-organic substance, which, from its constant 

 presence, its relations with the reserve-albuminoids, and its chemical 

 composition, must be the first organisation-product of phosphoric acid. 

 This phosphor-organic acid has the composition PCH 5 5 ; it is in fact a 

 compound of formaldehyd and phosphoric acid. It is a bibasic acid, all 

 the salts of which are amorphous. In combination with the reserve- 

 albuminoids, potassium phosphor-organate forms the grains of aleurone, 

 the combination being a very unstable one. The author concludes with 

 remarks on the occurrence of inosite, a hexatomic alcohol, in the pro- 

 ducts of decomposition of phosphor-organic acid. 



Formation and Decomposition of Albumen in Plants.} — Herr E. 

 Schulze gives experimental evidence (derived apparently from culture ex- 

 periments on Leguminosseonly) in favour of his theory that the decompo- 

 sition of the albuminoids in germinating seeds results in the production 

 of a mixture of nitrogenous compounds which always consists partially 

 of amido-acids of the fatty and aromatic series, as well as of hexon-bases 

 (argidin, histidin, and lysin) ; these substances being also formed by the 

 decomposition of albuminoids by acids or by trypsin. A portion of 

 these primary products of decomposition is transformed, in the meta- 

 stasis of seedlings, into asparagin or glutamin, which are therefore 

 secondary products. The analysis of the substances contained in the 

 seedlings showed that, while the amount of leucin, tyrosin, and arginin 

 decreased with the growth of the plant, the proportion of asparagin 

 rapidly increased. 



Denitrification and Fermentation.§ — Herr H. Wolff employed for 

 these experiments four typhoid-like bacilli (including B. colt com. and 

 B. typhi murium) and two hay bacilli. All the bacilli reduced nitrates 



* Proc. Ainer. Ass. Adv. Sci., xlviii. (1899) pp. 293-7. 

 t Rev. Gen. de Bot. (Bonnier), xii. (1900) pp. 5-24, 65-73. 

 t Ber. Deutsch. Bot. Ges., xviii. (1900) pp. 30-42. Cf. this Journal, 1899, p. 56. 

 § Hye;ien. Rundschau, ix. pp. 1169-72. See Journ. Cliem. Soc, lxxvii. and 

 lxxviii. (1900) p. 298. 



