74 
SUMMARY OF CURRENT RESEARCHES RELATING TO 
which form a link between the thalloid and the foliose forms. 
While the leaves are the largest known among Hepaticae, the position 
of the sexual organs (archegones only have at present been observed) 
allies it with the thalloid forms. The cells of the stem are infested by 
a parasitic, or possibly symbiotic, fungus. 
Colura ornata sp. n. is epiphyllous ; the water-sack characteristic of 
the genus is surmounted by a comb-like projection from the surface 
of the leaf. A species of Plagiochila with water-sacks is also described. 
Kurzia crenacanthoidea , described by its discoverer as an alga, is in 
reality a species of Lepidozia with confervoid habit. 
Characeae. 
Histology of Characese.* — Dr. W. Overton’s researches on this 
subject relate mainly to two points : — 
(1) The nature of the spiny bodies found in the cells. The 
species examined for this purposes was chiefly Nitella syncarpa. 
They were found in all the mature internodes of the stem and leaves, 
where they obtain a diameter of 22 to 24 p, in the young oospheres, in 
the cortical cells of the oosperm, in the shield-cells of the antherids, 
occasionally in the manubria, but not in the other cells of the antherids. 
They are clothed with a distinct membrane, and often occur in dense 
masses, wdien they assume a polygonal form. Microchemical reactions 
show that they are of a proteid nature, and that they frequently contain 
tannin ; they are peculiarly resistant to the action of acids, even when 
concentrated. They may be compared to a certain extent with aleurone-> 
grains. The living cells of young internodes contain also a number of 
hyaline vesicles imbedded in the protoplasm, which are also clothed with 
a distinct membrane, and are clearly of a similar nature to the spiny 
bodies. In the species of Ghara examined ( G . fragilis and hispida ) no 
structures were found resembling either of those above described. 
(2) The structure of the hard envelope of the oosperm. This 
envelope is not lignified in the correct sense of the term ; i. e. it does 
not show the microchemical reactions of lignin, but rather those of 
cuticularized and suberized membranes. After removal of the calcareous 
deposit, the envelope of the oosperm of Gliara fragilis consists of three 
layers: — the outermost is nearly black, is furnished with spiral thickening- 
bands, and bears a number of short spines ; the middle layer is brown 
and smooth ; the innermost is the true membrane of the oosperm, is light 
brown and transparent, and is but slightly cuticularized. 
Algae. 
Algae of Behring’s Sea.f — Ilerr F. E. Kjellman describes the sea- 
weeds of this sea, which are partly of an Arctic, partly of a more 
southern character, with some peculiar to the region. Several new 
species are described, and one new genus of Phaeosporeae, Analipus, with 
unilocular zoosporanges, a horizontal almost crustaceous thallus, from 
which rise the fertile branches, simple, solid below and fistulose above. 
* Bot. Centralbl., xliv. (1890) pp. 1-10, 33-8 (1 pi.). 
f K. Svensk. Ve tensk.-Akad. Handl., xxiii. (1889) 58 pp. and 7 pis. See Bot. 
Centralbl., xliv. (1890) p. 150. 
