Dessaignes, who obtained it by oxidizing malic acid (Ann., 1858, 107, p. 251).
The female organs of certain cryptogams, for instance, exert a positive chemiotactic action upon the spermatozoids, and probably, as Pfeffer suggests, the chemical agent which exerts the influence is malic acid.
No other substance, at least, with which he experimented had a like effect, and it is possible that in the archegonium which contains the ovum malic acid is present.
MALIC ACID (HYDROXYETHYLENE SUCCINIC Acid), C4H605, an organic acid found abundantly in the juices of many plants, particularly in mountain-ash berries, in unripe apples and in grapes.
In the last years of his life he returned to the vegetable acids, and investigated citric, malic, oxalic and gallic acids.
Such bases occur almost exclusively in the dicotyledons, generally in combination with malic, citric, tartaric or similar plant-acids.
It may be prepared by the oxidation of fats and of fatty acids by nitric acid, and is also a product of the fermentation of malic and tartaric acids.
Synthetically it may ba obtained by reducing malic or tartaric acids with hydriodic acid (R.
The character of the acidity, however, changes, the free tartaric acid gradually disappearing, forming bitartrate of potash and being otherwise broken up. On the other hand, the free malic acid increases and the tannin decreases.
It crystallizes in prisms, containing one molecule of water of crystallization, the anhydrous form melting at 234-235° C. Nitrous acid converts it into malic acid, [[Hooc Choh Ch 2 Cooh]].
(All except d represent vertical sections of sporangiophore or sorus.) canal the spermatozoid, which in the Ferns has been shown to be attracted by reason of its positive irritability to malic acid, passes and fuses with the ovum.