ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 
855 
mentary or altogether suppressed on the lateral shoots ; the main shoot 
is altogether barren ; the flowers are unisexual but monoecious (^NotJio- 
fagus) ; (3) the foliage-leaves which subtend tbe fertile shoots are 
metamorphosed into bracts, and the inflorescence becomes a catkin, 
which is either bisexual (Platycarya) or more often unisexual (Betiilace®, 
most Jnglandese) ; (4) further reduction has taken place; some of the 
reproductive shoots are replaced by vegetative resting-buds {Castanea ) ; 
the female inflorescences are greatly reduced and inclosed in a cupule 
(Cupuliferae). 
Pericarp of the Barley-grain * — Dr. A. Zoebl gives an exhaustive 
description of the anatomy and histology of the integument or pericarp 
of the grain of Hordeum distichum and of the pales, chiefly from the point 
of view of its commercial value. The points specially described are the 
epiderm, the parenchyme of the pales, the awn, the layers of tissue of 
the pericarp itself, and the hairs on the pericarp. The author speaks 
of the walls of the epiderm of the pales which abut on those of the 
fibre-cells as being especially characterized by their abundant and 
strongly-developed pits. 
Integument of the Seed in Geraniaceae, Lythraceae, and Oeno- 
thereae.f — M. M. Brandza states that it is generally admitted that during 
the evolution of the ovule into the seed, the nucellus and inner integument 
of the ovule are absorbed by the embryo ; Euphorbiacese, Rosaceae and 
Rutaceae being exceptions. The author, however, to test this, has 
chosen three distinct families of plants, and his conclusions are as 
follows : — (1) In the Geraniaceae the integuments of the ovule persist, 
and give rise to the corresponding parts of the integument of the seed. 
(2) In the Oenothereae and Lythraceas it is the same, but the outermost 
layers of the nucellus also persist. 
Extrafloral Nectaries. J — Prof. F. Delpino describes the excretion 
of nectar from the under side of the six or seven leaves which for the 
time being are the uppermost on the stem of HeliantJms giganteus and 
H. tuherosus ; and a similar phenomenon, hitherto undetected, on the 
under side of the upper leaves of Glycine sinensis (Papilionaceae). The 
involucral scales of Centaurea montana also exude an abundance of a 
nectariferous fluid. In all these cases the object of the extrafloral nec- 
taries is the attraction of ants and other insects which feed greedily on 
the sweet fluid, and the consequent protection of the flowers. 
Temporary Ascidia in Sterculia.§— Prof. F. Delpino describes the 
peculiar development of the pistil of Sterculia platanifolia after fertiliza- 
tion, by which the carpids separate from one another, and each swells 
up into a bladder of considerable size. These bladders are temporary 
ascidia, filled with a noisome fluid, and covered on the inner surface 
with multitudes of multicellular glandular hairs. The author believes 
these structures to have a similar purpose to the calycine ascidia described 
by Treub \\ in Spathodea campanulata, and to perform a double function 
* Abhaudl. Naturf. Ver. Briinn, 1888 (1889) pp. 205-28 (20 figs.). 
t Bull. Soc. Bot. France, xxxvi. (1889) pp. 417-20. 
i Malpighia, iii. (1889) pp. 344-7. Cf. this Journal, ante, p 201. 
§ Malpighia, iii. (1889) pp, 339-44. H Cf. this Journal, 1889, p. 86. 
2 c 2 
