82 1) RECORD OF CURRENT RESEARCHES RELATING TO 



percentage, but distiuguislaed by containing a considerably greater 

 quantity of water, and only partially converted into sugar by the 

 action of acids. Tbe author has not been able to determine whether 

 this is an accidental accompaniment to the pigments, or what is its 

 relation to chlorophyll. 



Composition of Chlorophyll.* — Hoppe-Seylcr publishes a con- 

 tinuation of his work on chlorophyllan,"]- a crystalline substance 

 closely resembling chloroj)hyll, obtained from green grass. By 

 treatment with alcoholic potash, chlorophyllan yields, amongst other 

 l)roducts, an acid characterized by giving a splendid purple-coloured 

 ethereal solution, which exhibits very marked rose-red fluorescence. 

 For this compound — C^oB^siOs — Hoppe-Seyler proposes the name of 

 dichromatic acid. The absorption spectrum of the acid in ethereal 

 solution is marked by two bands between C and D, whilst the 

 spectrum of the fluorescent light from the same solution exhibits two 

 bright bands in exactly the same positions. 



Division of Chlorophyll-grains.;]: — J. Schaarschmidt summarizes 

 the observations of recent writers on the division of chlorophyll, 

 adding some also of his own. He states the general results obtained 

 to be that the chlorophyll-grain is capable of division in all plants ; 

 that the division is not efiected at any particular time of the year ; 

 and that it takes place in the same manner as the cell-nucleus, in two 

 ways ; most usually by a median zone and the formation of numerous 

 threads of protoplasm ; or by the formation simply of numerous 

 threads of protoplasm, in which case no formation of a median zone 

 takes place. 



The author enumerates 22 species of cryptogams, and 38 of 

 phanerogams, in which the division has been observed either by 

 himself or others. He claims to have observed that the surface of 

 the chlorophyll-grains is furnished with extremely fine cilia which 

 are usually placed at equal distances apart, and are colourless. They 

 were first observed in Boehmeria biloha, most distinctly in Hartwegia 

 comosa. 



Branching of Endogenous Organs from the Mother-organ- §— 

 An elaborate paper on this subject by H. Vouhone concludes with the 

 following summary of results : — 



1. From the young root a secretion is given off which acts as 

 a solvent on the tissue of the mother-organ, destrc^ying first the 

 turgidity of the cells, and then their primordial utricle, and thus 

 making way for the root. 



2. When the secretion cannot act in consequence of the nature of 

 the cell-wall, the quickly growing root exercises a mechanical pressure 

 on the obstructive tissue. In this resj)ect there is a difference in the 

 behaviour of different kinds of tissue. 



* ' Zeitschr. physiol. Cliemie.' See ' Nature,' xxii. (18S0) p. 279. 

 t See this Jourual, ante, pp. IIG and 2!)6. 



X ' Magyar Nuve'nytani Lapok,' iv. (1880) p. 33. See ' But. Centralbl.,' i. 

 (1880) p. 457. 



§ ' Flora,' Ixiii. (1880) p. 227. 



