366 
SUMMARY OF CURRENT RESEARCHES RELATING TO 
of the genera Bhizophora , Bruguiera, Ceriops, and Kandelia belonging to 
the Rhizophoreae, as well as others belonging to the Myrsinacese, Yerbe- 
naceoe, Myrtaceae, Combretaceae, Rubiaceae, Meliaceae, and PalmaB. 
The ovules of all Rhizophoreae possess, in their early stages, two 
integuments ; but the inner integument frequently becomes more or 
less completely absorbed, and in Bruguiera the embryo-sac forces its way 
through it, and spreads itself out between the two layers. Of the 4-6 
ovules in each flower all but one always abort. The embryo has two 
growing points, one of which penetrates the endosperm and bears 2-4 
cotyledons, which soon fill up the entire cavity of the outer integument 
and act as absorbing organs, while the radicular growing point, which is 
directed towards the micropyle, breaks finally through it and developes 
into the hypocotyl. All the nutrient substances of the mother-plant are 
applied to the nutrition of this hypocotyl, which may attain a length of 
1 metre. 
The fruit (or seed) of all mangrove-plants floats on the water. The 
roots, which strike into soil saturated with water, are adapted for the 
interchange of gases, and serve, therefore, as organs of respiration. 
They are abundantly provided with lenticels, and are negatively 
geotropic. 
Order of Succession of the Parts of the Flower.* — A series of obser- 
vations on this subject by Herr K. Schumann leads him to the conclu- 
sion that the prevalent theory that the parts of the flower are formed 
in spiral succession is not tenable in the greater number of cases. In 
the Lobeliaceae all the sepals always originate simultaneously, and the 
same is the case in many Campanulaceee, Rubiacete, and Caprifoliaceae, 
and in some species of Acer and Abutilon. The “ superposition ” of 
whorls is a distinguishing character of floral, as contrasted with vege- 
tative, shoots, and is always the result of contact, and of adaptation to 
the space at command. Where an outer whorl appears later than an 
inner whorl, as in the Primulaceae and Plumbagineae, it is always the 
result of intercalation. There may be extra-axillary flowers, corre- 
sponding to extra-axillary leaf-buds. The author adopts Schwendener’s 
view that purely mechanical influences outweigh all others in deter- 
mining the early development of plant-members, whether axial, foliar, 
or floral. 
Septal Glands of Kniphofia.j — Miss E. R. Saunders describes the 
nectar- glands on the septa of the ovary of several species of Kniphofia 
(Liliaceae). Their minute structure is detailed, and their development 
traced from the earliest stage. The saccharine fluid which they exude 
in large quantities when mature appears to be formed out of the starch 
contained in them at earlier stages. This change is doubtless effected 
by the protoplasm, and is presumably due to some ferment action. 
Development of Fleshy Pericarps.! — M. A. G. Garcin has examined 
in detail the structure and development of the fleshy pericarp in a large 
number of berries and drupes. In the ripe berry the mesocarp may 
consist of one, two, three, or four layers, and there may or may not be a 
* Neue Untera. iib. d. Bliiten-anschluss (10 pla.), Leipzig, 1890. See Bot. 
Centralbl., xlv. (1891) p. 220. f Ann. of Bot., v. (1890) pp. 11-25 (1 pi.). 
X Ann. Sci. Nat. (Bot.), xii. (1890) pp. 175-401 (4 pla.). 
