702 
SUMMARY OF CURRENT RESEARCHES RELATING TO 
follows: — Irt, VI, V, 16, II, III, IV. The spectrum of the alcoholic 
extract differs only in the absence of 16, and in a slight shifting of all 
the bands. These results differ from those of most other authors, in 
consequence of the mode of treatment. Instead of first boiling in 
water, the author extracts the chlorophyll at once with cold 95 per cent, 
or absolute alcohol. The alcoholic extract always contains two green 
and two yellow pigments. The two latter are separated by precipitating 
by baryta, and extracting the precipitate by alcohol. If this extract is 
then agitated with petroleum-ether, the carotin is dissolved in the ether, 
the xanthophyll in the alcohol. They are easily distinguished from one 
another by various reactions. 
The two green pigments are termed by the author amorphous and 
crystalline chlorophyll. Their relative amount differs greatly in dif- 
ferent leaves. Amorphous chlorophyll is characterized by the complete 
absence of band V from its spectrum. It is more soluble in benzin, 
petroleum -ether, and carbon bisulphide, than in alcohol. Crystalline 
chlorophyll may be obtained from certain leaves (e. g. Dianthus bar- 
batus, Dahlia variabilis ) simply by evaporating the alcoholic extract, 4 and 
purifying the crystals by water and benzin. They are completely in- 
soluble in petroleum-ether, carbon bisulphide, and ordinary benzin ; 
soluble in alcohol, ether, chloroform, and pure benzin. It is probable 
that living leaves contain this kind only of chlorophyll. 
The alcoholic extract of Oscz7Za£on’a-filaments contains carotin, phy- 
coxanthin, and both kinds of chlorophyll. Phycocyan is not soluble in 
alcohol. 
The same author * * * § finds, in etiolated leaves, besides xanthophyll and 
carotin, a pigment to which he gives the name protochlorophyll. It 
displays a distinct red fluorescence, and exhibits a line in its absorption- 
spectrum corresponding to band III of chlorophyll, and a second 
characteristic band at some distance from band II of chlorophyll. 
Band I is entirely wanting. The spectrum attributed by Pringsheim 
and Tschirch to etiolin is probably a combination of the spectra of a 
modified chlorophyll, of protochlorophyll, of carotin, and of xanthophyll. 
Chemistry of Chlorophyll.! — In his latest contribution to this sub- 
ject Dr. E. Schunck gives the result of investigations on various 
products derived from chlorophyll, especially on the preparation of pure 
phyllotaonin. 
Occurrence of several Chlorophylls in the same Plant.! — In the 
leaves of the lucerne M. A. Etard finds no fewer than four distinct 
chlorophylls. To one of these, especially characteristic of the plant, 
an amorphous chlorophyll, he gives the name medicagophyll. 
Formation and Localization of Fatty and Essential Oils.§ — Ac- 
cording to the researches on this subject of M. E. Mesnard, fatty oils 
are not, except in the case of grasses, localized in 'special layers of 
cells. They are found in all the cells of a particular region, such as the 
endosperm, pulp of fruit, leaf, rhizome, &c. In seeds the albuminous 
* Op. cit., xiii. (1894) pp. 201-17. See Bot. Centralbl., lix. (1894) p. 284. 
t Proc. Boy. Soc., lv. (1894) pp. 351-6. Cf. this Journal, 1893, p. 59. 
X Comptes Rendus, cxix. (1894) pp. 289-91. 
§ Ann. Sci. Nat. (Bot.), xviii. (1894) pp. 257-397 (3 pis.). 
