704 : 
SUMMARY OF CURRENT RESEARCHES RELATING TO 
Elaioplasts and Elaiospheres.* — The literature of elaioplasts is 
reviewed by Dr. A. Zimmermann, both with reference to flowering 
plants and to Hepaticae. The somewhat similar bodies found by 
Eadlkofer and others! in the spongy and palisade parenchyme of 
plants belonging to several natural orders, are distinguished by Lidforss 
under the name elaiospheres . | They usually give the reaction of oil. 
Sphero crystals of Agave.§ — In the bracts, flowers, and fruits of 
Agave mexicana and coerulescens preserved in alcohol, Sig. L. Re finds 
reddish or yellowish bodies which exhibit all the ordinary reactions of 
spherocrystals. 
Proteolytic Ferments in Seedling*s.|| — Herr R. Neumeister has em- 
ployed the property of fibrin of absorbing ferments from their solutions 
to determine their presence in growing seedlings. Fresh fibrin was 
soaked in aqueous extracts of the seedlings, and the fibrin then removed 
and placed in acid and alkaline mixtures. By this process it was 
demonstrated that a number of seedlings (barley, poppy, maize, wheat, 
rape) contain a ferment which dissolves proteids. It is not present at the 
earliest stages, but increases with the growth of the plant. Like pepsin, 
it works only in acid liquids, a vegetable acid like oxalic being necessary. 
It appears to produce peptone out of the proteids, which assists in the 
nutrition of the seedling. In other seedlings (lupin, vetch, pea, rye, oat) 
the ferment was not found. 
Calcium Oxalate in Solution.^ — M. E. Belzung points out that 
calcium oxalate may occur in plants, not only in the crystallized form, 
but also in solution in the cell-sap. It is then dissolved in one of the 
organic acids, and probably in a state of unstable combination with it, 
as calcium citroxalate or oxoxalate, according as the dissolving acid is 
citric or oxalic. In this condition it may play the part of a reserve- 
nutritive-substance for the plant. The cell-protoplasm is protected from 
the poisonous influence of free oxalic acid or an oxalic salt in the cell- 
sap by the tonoplast of the vacuole. 
C3) Structure of Tissues. 
Wood and Pith at the bounds of the Annual Growth.** — HerrE. 
Jahn has made a series of observations on a great variety of woody 
plants, for the purpose of determining the nature of the tissue on the 
confines of two annual rings of growth. He finds that, in the w’oody 
portion, the width of the ring diminishes rapidly as soon as it reaches 
the region of the bud-scales. The cells become shorter and narrower, 
and in Dicotyledons there are only parenchymatous cells and tracheids. 
The predominant forms of thickening are reticulate and spiral. There 
is an evident tendency to facilitate a connection, in the radial direction, 
with the next annual ring. In the pith the radial arrangement of the 
cells is no longer apparent. In the region of the bud-scales is the inter- 
mediate pith, a tissue of closely packed cells possessing pores, and filled 
* Bot. Centralbl., 1894, Beik., pp. 165-9. f Cf. this Journal, ante , p. 467. 
J See Acta Univ. Lund., xxix. (1892, 93). 
§ Ann. R. 1st. Bot. Roma, v. pp. 38-40. See Bot. Centralbl., lix. (1894) p. 339. 
|| Zeit. Biol., xxx. pp. 447-63. See Journ. Chem. Soc., 1894, Abstr., p. 290. 
Journ. de Bot. (Morot), viii. (1894) pp. 213-9. 
** Bot. Centralbl., lix. (1894) pp. 257-67, 321-9, 353-61 (1 pi.). 
