218 
SUMMARY OF CURRENT RESEARCHES RELATING TO 
of the oogone till that of complete coalescence no excretion of nuclear 
substance was observed. 
The author finds on this species of CEdogonium an undescribed para- 
sitic fungus, to which he gives the name Lagenidium Syncytiorum. It 
prevents the formation of septa in the host, but has apparently no inju- 
rious effect on the division of the nuclei or cells. 
Anatomy and Physiology of Fucoidese.* — Herr B. Hansteen has 
investigated several points in the structure of some species of Fucoideae, 
especially Pelvetia caniculata , Sargassum bacciferum , and Fucus serratus. 
Pelvetia differs from Fucus in the entire absence of a mid-rib to the 
thallus. In both genera the thallus divides by a regular dichotomy, 
and grows by a strongly differentiated apical cell. The cells of the 
assimilating tissue are connected with one another by pores. Trichomic 
structures occur within the bladders of Sargassum. 
The substance of which the granules found in the assimilating tissue 
of the Fucoideae is composed — termed by Schmitz PhaeophyceaB-starch — 
is, according to the author, a carbohydrate of the percentage composition 
C 6 H 10 O 6 , to which he gives the name fucosan. It is probably the first 
product of assimilation, and is closely related to the phaeoplasts, but 
appears to originate outside them in the cytoplasm. The microchemical 
reactions of fucosan are given in detail; the granules are partially 
soluble in cold, completely so in warm water, and are beautifully stained 
by methyl-green. Gunther and Tollens’s fucose is probably a partially 
inverted fucosan. 
Algae of German New Guinea. | — Herr F. Heydrich, in a collec- 
tion of Algae from Kaiser- Wilhelms-Land, describes the following new 
species: — Oscillatoria microscopica , Edocarjpus elachistseformis, Streblo- 
nema minutula , Bostrychia (?) crassula. Full descriptions are also given 
of Anadyomene Wrightii , Valonia Forbesii, Dictyosphseriafamlosa, Sebdenia 
ceylanica , and Halymenia lacerata. In Anadyomene Wrightii a mode of 
propagation is described by akinetes which develope into new individuals 
without a period of rest. In Valonia the apices of the roots appear, by 
their septation, to play an important part in the alternation of genera- 
tions. Sebdenia ceylanica (Harv.) Hevdr. is a synonym of Halymenia 
ceylanica Harv. and of Kallymenia exasperata Zan. 
Hairs and Bristles of the Chgetophorese.J — M. J. Huber points 
out the vague manner in which these terms have been used in the 
description of Algae. He proposes to limit the term hair ( pilum ) to 
hair-like appendages, whether unicellular or pluricellular, bristle (seta) 
to local prolongations of a vegetative cell, formed either by a simple 
excrescence of the cell-wall, or by an invagination of layers of proto- 
plasm. The former are nucleated, the latter not. With regard to the 
genera which make up the Chaetophoreae, Chsetophorci, Draparnaldia , 
and Stigeoclonium are characterized by multicellular hairs which termi- 
nate branches of an erect and free thallus. In Herposteiron the erect 
branches are replaced by unicellular hairs ; in Aphanochsete by invagi- 
nated bristles; in Chsetopeltis by mucous bristles. Among the forms 
* Jahrb. f. Wiss. Bot. (Pringsheim), xxiv. (1892) pp. 317-62 (4 pis.), 
t Ber. Reutsch. Bot. Gesell., x. (1892) pp. 458-85 (3 pis. and 1 fig.), 
t Journ. de Bot. (Morot), vi. (1892) pp. 321-41 (11 figs.). 
