ZOOLOGY AND BOTANY, MICROSCOPY, ETO. 
497 
amorphous pigment soluble in water, a red amorphous pigment soluble 
in water (“ bulgarerythrin ”), and a yellow fat. 
From Arcyria punicea (Mycetozoa) four pigments can be extracted by 
alcohol, viz. a yellow resinous acid, scarlet when solid, soluble in 
benzol (“ arcyric acid ”), a brownish-yellow resinous acid insoluble in 
benzol, a yellow fatty acid, and a yellow acid soluble in alcohol, in- 
soluble in ether and water. The scarlet colour of the organism appears 
to be due to the first of these. 
New Lichen-acid.* — Prof. W. Zopf has extracted from an alpine 
lichen Tliamnolia vermicularis , distinguished by its chalky or greyish 
white colour, a crystallizable acid which he regards as new, and to which 
he gives the name thamnolic acid. It occurs in the cortex of the 
lichen, and its properties are described in detail. 
Vegetable Ferments. j — Prof. J. R. Green gives a detailed account 
of what is known respecting the various kinds of ferment occurring in 
the vegetable kingdom. He classifies them under four groups, viz. : — 
(1) Carbohydrate enzymes, including the various kinds of diastase, inu- 
lase, invertase, the cytohydrolysts which attack cellulose, and the 
ferment which forms vegetable jelly from pectic substances; (2) Glu- 
coside enzymes, including emulsin or synaptase, myrosin, erythrozyme, 
and rhamnase ; (3) Proteo-hydrolytic enzymes, including vegetable 
pepsin, trypsin, and vegetable rennet ; (4) Glyceride enzymes, which 
decompose oils. 
Of diastase there appear to be two kinds, one concerned in transloca- 
tion, the other in secretion, of which the latter is the more active ; the 
former dissolves starch-grains without, the latter with corrosion. The 
action of diastase is always one of hydrolysis. Inulase is found where 
inulin replaces starch in various Composite. Invertase has the power of 
inverting cane-sugar, or of hydrolysing it into dextrose and levulose. 
Cytohydrolysts have been discovered in the germinating barley-grain 
and in certain fungi. Emulsion has been found in certain species of 
Amygdalus and Cerasus or Prunus, and is active in the formation of 
prussic acid ; myrosin is the characteristic enzyme of the Cruciferae ; 
rhamnase occurs in Bhamnus infectorius ; erythrozyme in madder-root. 
The ferments of Brosera, Dionsea , Pinguiculci, and other insectivorous 
plants are pepsins ; the best-known trypsins are the ferment of Carica 
Papaya, and that of the fig ; a rennet occurs in the latex, the bast, the 
leaves, the flowers, and the seeds of various plants. Glyceride enzymes 
have been found in various oily seeds. 
Besides the above-mentioned groups, the author describes the enzymes 
of fungi ( Fusarum , Botrytis, Torula Urese, &c.), and those of bacteria, 
and also states what is known respecting zymogens or enzyme- 
generators. 
The action of the enzymes is stated to be, in all cases except that of 
myrosin, one of hydration. It is in no way different from an ordinary 
chemical reaction. Some of them act only intracellularly, and do not, 
during their activity, leave the cells in which they are secreted ; while 
others are secreted in particular cells, and are excreted by them to work 
upon substances contained elsewhere. 
* Hedwigia, xxxii. (1893) pp. 66-9. 
t Ann. Bot., vii. (1893) pp. 83-137. 
