634 
SUMMARY OF CURRENT RESEARCHES RELATING TO 
parts connected together, containing groups of cells, encapsuled within 
one another in nests, with cell-walls more strongly thickened on one 
side. 
Haliarachne. Filaments multicellular, arranged in two layers in a 
roundish or elongated free-swimming gelatinous stratum, radiating from 
its centre like the bent legs of a spider, and curved into a hook at the 
end. 
Katagnymene. Filaments multicellular, free-swimming, with thin 
close-fitting sheaths, lying in a broad swollen gelatinous general sheath, 
very readily breaking up into fragments. 
Pseudo-pleurococcus g. n.* * * § — Dr. Julia W. Snow establishes this 
genus of lowly algae, obtained from the bark of trees, including two 
species, P. botryoides from America, and P. vulgaris from Switzerland. 
The following is the diagnosis of the genus : — Thallus ; in the atmo- 
sphere either unicellular or forming parenchymatous masses of cells of 
various sizes; in liquid media filamentous; cells 6*5-8 /jl in diameter; 
chromatopliore parietal, but not completely lining the membrane ; nucleus 
single. Both species contain a pyrenoid in each cell. The existence of 
this genus is regarded by the authoress as accounting for the alleged 
polymorphism of Pleurococcus , for which it is easily mistaken. 
New Species of Oscillatoriese.f — M. M. Gomont enumerates and 
gives diagnoses of all the new species of Oscillatoriacese discovered 
since the publication of his monograph of the family in 18924 A con- 
siderable number of them have been found as a coating on damp rocks. 
M. Gomont takes the opportunity of defending some points in his 
classification of the family which have been attacked. 
/ 3 . Schizomycetes. 
Nature of Bacteria and their Position among Fungi. § — According 
to Dr. W. Winkler bacteria develope from plasmodes, which consist of 
plasma containing granules, and often exhibit amoeboid movements and 
small vacuoles. From the plasmodes are produced bacteria, plasmodes, 
thallus forms (filidia, membranes, &c.), bacterioblasts, and sporanges. 
Megaspores originate in the sporanges, and macrocysts in plasmodes. 
The basis of all bacterial colonies and zoogloeae is the plasmode. The 
author appears to see a connection between bacterial and protozoal plas- 
modes, and regards the involution forms of bacteria as regular stages in 
the developmental cycle Sarcina-forms are bacterioblastic fission plas- 
modes, and the bacteroids of Leguminosas are bacterioblasts. 
Reducing Properties of Bacteria. || — Dr. F. Muller employed two 
pigments, litmus and methylen-blue, in an investigation on the reducing 
properties of bacteria. Both of these possess the characters essential for 
such an examination ; their oxidation stage is easily reduced, and their re- 
duction-stage readily reoxidised by atmospheric oxygen ; they are easily 
soluble in water, the medium remaining clear ; they exert no poisonous 
* Ann. of Bot., xiii. (1899) pp. 189-95 (1 ph). 
t Bull. Soc. Bot. France, xlvi. (1899) pp. 25-41 (1 pi.). 
t Cf. this Journal, 1892, p. 838. 
§ Centralbl. Bakt. u. Par., 2 te Abt., v. (1899) pp. 569-79 ; 617-29 (2 pis.). 
H Op. cit., l te Abt., xxvi. (1899) pp. 51-63. 
