232 
SUiniARY OF CURRENT RESEARCHES RELATING TO 
broad ; their membrane is thin and colourless, and is closely covered 
with minute elevations. Each group of uredospores is surrounded by a 
circle of cylindrical paraphyses swollen at the base. A variety or very 
nearly allied species, U. Cissi , attacks Cissus rbombifolia. 
JEcidiuin esculentum.* * * § — Under this name Dr. A. Barclay describes 
a fungus belonging to the Uredineae which grows on the flowering shoots 
of Acacia ebumea in India, causing hypertrophy and other malforma- 
tions; its fecidia are largely eaten by the natives. 
Mycetozoa. 
Development of Myxomycetes and new Species.f — Ur. G. A. Bex 
points out that, although the sporange of many mature species of Myxo- 
mycetes exhibit-s remarkable variation in form, colour, and structure, no 
such tendency to variation exists in the plasmodial stage, the plasmode 
itself being unvarying in colour and in other physical characters. The 
variations in the sporangial stage the author believes to be due to local 
external influences, especially to differences in the temperature and 
moisture of the atmosphere. The above remarks are illustrated 
especially in the case of Tubulina cylindrica. 
The same author i describes the following new American species of 
Myxomycetes : — Physarum tenerum, Tricilia subfusca , and T. erecta. 
Protophyta. 
a. Scliizopliyceae. 
Vegetation of Hot Springs. § — Mr. W. H. Weed enumerates the 
AlgaB found in the hot springs on the American continent. Of these 
there are no less than 3500 in the Yellowstone district, the temperature 
of which reaches 85° C., while in the Brewer-spring in California it 
rises as high as C. They consist of peculiar species of Protococca- 
cese, OscillariaoeEe, and Confervaceae, with a comparatively small number 
of Desmidiaceae and Diatomaceae, generally the same species as in cold 
waters. They thrive best when the water is somewhat alkaline ; their 
colour is often a bright red and green, and varies with the temperature 
of the water. They are always eventually encrusted by siliceous or 
calcareous sediment. 
Zoochlorellae and Lichen-gonids.|| — Herr M. W. Beyerinck gives 
further details of his pure culture of some of the lowest Algae (Proto- 
phyta) Since the organism known as Chlorococcum protogenitum Bbh. 
does not appear to produce zoospores under any conditions, he proposes 
to establish it as the type of a new genus under the name Chlorella 
vulgaris. The cultures of this and of the new species Baphidium naviculare 
were made by introducing a drop of the water containing them into a 
nutrient fluid consisting of ordinary ditch-water boiled with 10 per cent, 
gelatin. Scenedesmus acutus cultivated in this way was found also to 
* Journ. Bombay Nat. Hist. Soc., v. (1890) pp. 1-1 (1 pi.) See Bot. Centralbl., 
xliv. (1890) p. 322. t Bot Gazette, xv. (1890) pp. 315-20. 
+ Proc. Acad. Nat. Sci. Philadelphia, 1890, pp. 192-6. 
§ Amer. Naturalist, xxiii. (1889) pp. 391-400. 
Bot. Ztg., xlviii. (1890) pp. 725-39, 711-51, 757-68, 782-5 (1 pi.). Cf. this 
Journal, 1890, p. 757. 
