ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 
319 
discussed. Among the ten species of special interest is a novelty — 
Peridinium Suttoni — which is described and figured. Figures of six 
other species are given. A. G. 
Fresh-water Algae of New Caledonia. — Nellie Carter ( Journ . 
Linn. Roc. Bot., 1922, 46, 47-68, 1 pi. and figs.). Little was known 
previously of the fresh-water algae of New Caledonia. The present 
collection, made in 1914 by R. II. Compton, has yielded about 170 
species. It is rich in diatoms (60 species), and fairly rich in filamentous 
Chlorophyceae, which are plants of the running streams. The Cyano- 
phyceae, subaerial plants, proved very interesting, supplying a new 
genus, Rosaria , and three new species. Desmideae, which require still 
water and permanent boggy conditions, were not abundant ; they princi- 
pally consist of species of Closterium and Cosmarium. Rosaria ramosa 
is a moniliform uniseriate branched filament related probably to Hapalo- 
siphon, but is devoid of heterocysts and without a sheath. It grew in 
association with Mastigocoleus obtusus , which also is destitute of hetero- 
cysts. Scytonema Hieronymi, described from Samoa by Schmidle, is 
so closely associated with a fungus as to form a lichenoid compound. 
A. G. 
Contributions to the Diatom- Flora of Bavaria. — Anton Mayer 
(Denkschr. Kgl. Bayr. Bot. Gesellsch. Regensburg , 1917, 13, 1-152, 
12 pis. and figs.). This report contains lists of the diatoms of the 
Fichtelgebirge, the Bayrische Walde, Dillingen on the Danube, a fish- 
pond at Kondrau, and other sources ; also critical notes, numerous 
figures and distribution-tables, constituting several hundreds of records. 
A. G. 
Moisture Relations of Terrestrial Algae. I. Some General 
Observations and Experiments. — F. E. Fritsch ( Annals of Bot., 
1922, 36, 1-20, 2 figs.). An account of experiments and observa- 
tions made in field and laboratory on Pleurococcus Naegelii Chod., the 
Hormidium stage of Prasiola crispa, and Zygnema ericetorum. The 
author’s conclusions are "as follows 1. The protoplasts of the terre.- trial 
algae examined have either no large vacuoles ( Pleurococcus and Hor- 
midium ) or but few of them ( Zygnema ), the sap being dispersed through 
the cytoplasm. 2. In drought much of this sap is retained, more so in 
Hormidivm and Pleurococcus than in Zygnema. 3. In drouglit con- 
traction occurs, but the protoplast remains closely invested by the 
cell-wall ( Pleurococcus and Hormidium ), or in contact with it at certain 
points (Zygnema'). 4. Hence moisture imbibed into the walls from the 
atmosphere will reach the protoplast, especially in Pleurococcus and 
Hormidium. 5. Pleurococcus does not appreciably contract on drying, 
but Hormidium evidently contracts and shows a longitudinal folding of 
the walls along special lines of weakness. In Zygnema the amount of 
contraction is variable. The capacity for absorbing moisture is least 
in Pleurococcus and greatest in Hormidiunt , but smaller than in aquatic 
algge. 6. These terrestrial algge therefore (especially Pleurococcus) 
require but little moisture to replace that lost in desiccation. 7. Appre- 
ciable amounts can be absorbed when the air is very humid ; and 
probably some growth occurs then. 8. Terrestrial algge, as compared 
Y 2 
