ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 
507 
the same purpose ; they consist chiefly of a permanent parenchyme filled 
with food-material, and may be swollen into the form of a tuber. 
The roots of herbaceous plants may live only for a single year or for 
several years, or may have an apparently perennial existence. They may 
be produced only at one or at two different periods in the same year. 
The same species may have more than one hind of root, and these may 
or may not pass into one another by insensible gradations. 
Absorption of Nitrogen by Plants.* * * § — From experiments made on 
Pisum sativum , Polygonum Fagopyrum , Avena saliva , and Sinapis alba , 
Herr L. Richter concludes that of these plants, the pea only, and not 
mustard, buckwheat, or oat, has the power of making direct use of the 
free nitrogen of the air; and that this power is independent of the 
tubercles. Combination with nitrogen in the soil takes place where 
there is otherwise a deficiency of assimilable nitrogen. 
Germination of Anemone apennina-t — Herr F. Hildebrand notes 
some remarkable peculiarities in the germination of this plant. The 
lower part of the stem of the cotyledons has all the appearance and 
functions of a root, being densely covered with hairs. At the base of 
this hairy structure appears a slight swelling, which gradually increases 
in size into the appearance of a tuber. Both the upper smooth and the 
lower hairy portion of the axis increase in length, so that the tuberous 
structure is forced lower and lower into the soil. The first leaf now 
makes its appearance, not between the two cotyledons, but on the upper 
surface of the tuber, by the side of the cotyledonary stalk ; while a few 
secondary roots are put out laterally from the primary one. Between 
the cotyledonary stalk and the first leaf is the true apex of the ascending 
axis, from which are developed the remaining leaves in the following 
year. 
Germination of Heritiera littoralis.? — M. J. G. Boerlage describes 
the contrivances by which the seeds of this tree, belonging to the 
Sterculiacese, and widely distributed on the shores of the Eastern 
Archipelago, are protected from the injurious effect of sea-water, when 
the fruit falls into the sea, permitting them to escape only when thrown 
up on the shore. 
Bleeding of Woody Plants. — Prof. H. Molisch has made a variety 
of observations on the flow of sap from the stem of woody plants when 
wounded. 
In the case of palms § — Cocos and Arenga — the bleeding, when the 
inflorescence is amputated, is not due to root-pressure. No sap escapes 
from borings at the base of the stem, though it pours out abundantly 
at higher parts, even at a height of 19—28 in., when the tree is ir 
full leaf. The spadix continues to bleed for one or two days after 
being amputated. The origin of the osmotic pressure appears, there- 
* Landwirtsch. Vers.-Stat., li. (1898) pp. 221 et sea. See Bot. Centralbl., lxxviii. 
(1899) p. 90. 
t Ber. Deutsch. Bot. Gesell., xvii. (1899) pp. 161-6 (1 pi.). Cf. this Journal, 
1892, p. 390. 
t Ann. Jard. Bot. Buitenzorg, 189S, 2 me Suppl., pp. 136-42 (1 pi.). 
§ S.B. k. k. Akad. Wiss. Wien, Dec. 1st, 1898. See Oesterr. Bot. Zeitschr., xlix. 
(1899) p. 74. 
