ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 
443 
Bessey finds stomates of peculiar form. The epiderm is of extraordinary 
thickness, and the stomates have long narrow chimney-shaped openings 
above them, terminating in hollow papillae which project some distance 
above the surface. 
Pyrola aphylla.* * * § — Mr. T. Holm has made a detailed study of the 
structure of this plant, and asserts, in opposition to the statement of 
previous observers, that it is not leafless, and is neither a parasite nor a 
saprophyte. It produces underground shoots, after the manner of other 
species of the genus, which bear rosettes of leaves at their apex, of quite 
a normal structure, with chlorophyll tissue. The root has no haustoria. 
The plant possesses a remarkable facility of propagating itself by means 
of axillary buds developed on the underground stems, and of adven- 
titious buds produced on the roots. 
j8. PhysiologT. 
(1) Reproduction and Embryology. 
Embryology of Composite, j — Mdlle. M. Goldflus finds that, in the 
species of Compositee examined, the antipodals play an important part 
in the early stages of the maturing of the fertilised ovule. They become 
superposed, and frequently multiply by division. They remain in com- 
munication with the base of the embryo-sac by an axial row of elongated 
cells which performs the function of a pseudo-chalaza connecting the 
termination of the periovular bundles with the antipodal conducting 
apparatus. Their position, structure, and contents show that they 
perform an active part in the digestion of the pseudo-nucellus (the inte- 
rior portion of the integument), similar to that of the epithelial cells. 
This interior layer of cells of the integument can no longer be regarded 
as a protective layer. 
In some genera (Aster, Chrysanthemum, Leucanthemum) the terminal 
antipodal is swollen to a club-shaped form, a kind of pseudopode which 
projects into the tissues of the ovule. The size of the embryo-sac in 
proportion to that of the ovule varies greatly, as also does the structure 
of the digestive epithelial layer. In Helianthus the antipodals are of 
remarkable size, exceeding that of the remainder of the embryo-sac 
before impregnation, and even during the early stages of the development 
of the ovule. The antipodals are more cyanophilous than the epithelial 
cells, whilst the rest of the active cells of the embryo-sac are erythro- 
philous. 
Development of the Embryo in Lilaea subulata.J — Prof. D. H. 
Campbell finds the development of the embryo in this plant to corre- 
spond with that which occurs in other lowly organised Monocotyledons. § 
The sporogenous tissue of the stamen is not hypodermal in its origin, 
but arises from the plerome, as in Naias and Zannichellia. The ripe 
pollen-spore has two cells ; the generative nucleus remains undivided in 
the ripe spore. The archespore of the ovule is hypodermal, and a tape- 
tal cell is cut off from it. The primary sporogenous cell of the ovule 
* Bot. Gazette, xxv. (1898) pp. 246-54 (1 p].). 
t Arch. Sci. Phys. et Nat., v. (1898) pp. 390-2. 
% Bot. Gazette, xxv. (1898) pp. 1-28 (3 pis.). 
§ Cf. this Journal, ante , p. 322. 
2 H 
1898 
