738 
SUMMARY OF CURRENT RESEARCHES RELATING TO 
is characteristic of vegetable mucilages, and form round the seed a 
colourless, continuous and apparently homogeneous pellicle. When 
placed in water, a large part of the internal substance of the cells is 
immediately reduced to mucilage, and swells considerably. 
The mucilage-cells of Sisymbrium Sophia, Teesdalia Iberis, Hutchinsia 
petrsea , and Arabis Thaliana are constructed on nearly the same plan as 
those in Capsella. 
In the various species described, notwithstanding some individual 
variations, there is a remarkable similarity in the structure of the cell. 
There is always a wedge-shaped portion of amorphous cellulose, often 
thin at the summit, and in the remainder of the cell there is a striation, 
the striae of which are in the direction of the axis of this column. 
The author has embraced in his observations 90 species of the 
natural order Cruciferae. 
Secretory Apparatus of Papilionaceae.* — Mr. W. Russell states 
that secretory cells were first pointed out in the Papilionaceae by Sachs 
in Phaseolus ; but it was Trecul who more exactly determined their 
precise nature. As a conclusion the author states that tannin is in the 
Papilionaceae an excretory product, which is first localized in special 
cells analogous to laticiferous cells ; these appear in the bundles before 
their differentiation into xylem and phloem. 
Mucilaginous Endosperm of Leguminosse.f — Herr H. Nadelmann 
states that in all cases where the seeds of Leguminosae possess an endo- 
sperm, the walls of the endosperm-cells are provided with secondary 
thickenings, consisting of true mucilage, not cellulose-mucilage. From 
an examination of the structure of this endosperm in a large number of 
species, he draws the following general conclusions. 
The mucilage in these secondary thickenings serves in the first place 
as a reserve food-material ; they are used up in the germination of the 
seed. In the cells of the cotyledons of the seeds of Leguminosae, the 
secondary thickenings always consist of cellulose or amyloid, not of 
mucilage ; they serve, however, the same purpose. The mode in which 
the absorption of these secondary thickenings of the endosperm-cells 
takes place during germination varies in different cases. Whether these 
thickenings occur in the endosperm-cells or in those of the cotyledons, 
this absorption is accompanied by the formation of transitory starch in 
the cotyledons. Where this mucilage is present in large quantities, 
other reserve-substances, except starch, are nearly or entirely absent. 
The mucilage may either be directly formed as such, or may be first 
produced as cellulose, and then transformed into true mucilage ; when, 
in the cells of the ripe cotyledons, the thickenings consist of amyloid, 
they are formed directly as such. 
Anatomy of Saxifragacese.J — Hr. K. Leist treats in great detail 
of the anatomical structure of the genus Saxifraga, describing its variations 
in the different species. In the stem the course of the vascular bundles 
presents remarkable deviations according to the species ; S. Cotyledon 
* Rev. Gen. de Bot. (Bonnier), ii. (1890) pp. 341-4. 
t Jahrb. f. Wiss. Bot. (Pringsheim), xxi. (1890) pp. 609-91 (3 pis.), 
j Bot. Centralb]., xliii. (1890) pp. 100-3, 136-42, 161-71, 233-8, 281-8, 313-22, 
345-53, 377-82 (6 figs.). 
