CURRENT LITERATURE. U1
Algae.
Carter, N. Trachelomonas inconstans, a new flagellate. New Phytologlst. Vol. XV11I, Nos. 3 & 4 pp. 118-110.
In this paper the writer describes a new species of Trachelomonas collect- ed from a rainwater pool near longmoor Pool at Sutton Park, Warwick- shire. The distinctive feature is the presence of a prominent nodule or spiny excrescence at the posterior end of the organism. The cell is enclosed in a case whose wall is strongly impregnated with iron and has minute pores within its thickness. These pores become quite distinct after staining with haematoxylin.
Bristol, B. M. Retention of vitality by Algae. Neio Phytologist. Vol. XVIII, Nos. 3 it 4 pp. 92-107.
<• The author records spores of a large number of algae showing retention of vitality for a very long period, sometimes as many as 70 years. Samples of soil were taken which were bottled 45 to 70 years ago and put in sterilized culture-media. After some time a number of algal species made their appear- ance in the cultures. Thus two algae, namely, Notstoc muscontm Kutz. and Nodularia Harveyana (Thwaits) Thuret, were found in nearly all the cultures, even in those which contained soil about 70 years old; Anabcena oscillaroides Bory. var. terreseri'i n. var , Cyliiidros^ermnmlichenifoime (Bory) Kutz. and Chlorococcum humicola (Naeg.) Rabenh. grew again after 59 years' rest; Trochiscia aspera (Reinsch) Hansg., Stichococcusbacillaris Naeg. and Nitzschia Palea (Kutz) W. Sm. after 48 years' rest and Anabcena laxa A. Br. (?) after 46 years' rest.
Carter, N. Studies on the Chloroplasts of Desmids II. Annals of Botany, Vol. XXXIII, pp. 295-304.
In this paper the chloroplasts of a number of species of Micreslerias are described. There is normally one chloroplast in each semicell. Each chloro- plast consist of a more or less distinct axile plate parallel to the front faces with a number of ridges arising from it, which project towards the cellwall in different directions. In flatten ed-celied species the ridges are insignificant or even absent, while in thick-walled species they are very large and sometimes branched. In thinner cells there are more pyrenoids than in thicker ones. Each chloroplast is hollowed out in the centre of the cell to accommodate the nucleus.
Carter, Nellie. On the cytology of two species of Characiopsi s< New Phytologlst, Vol, XVIII, Nos. 5 it 6 pp, 177-18G.
The author has worked out in detail the cytology of Cliaraciopsis Naegli- (A.Br.) Lemm. and Ch. saccata n.sp. The- interesting points about Ch. Naeglii are the internal hollow invaginations of the cell-wall into the cytoplasm t numerous disc-like ohroraatophores which fill most of the cell cavity, a very large number of nuclei (sometimes more than sixty), absence of pyrenoids, and the presence of oil as its food reserve.
The species Ch. saccata is characterised by its acute apex, no internal invaginations of the cell wall, fewer and thinner chromatophores occupying only the peripheral portion of the cell cavity, fewer nuclei and their peripheral position.
She then describes a species of Characium, Ch. Aibgustum A. Br., for com- parison with the two species of Chataciopsis described above, and points out
