272 SUMMARY OF CURRENT RESEARCHES RELATING TO 



Protozoa (Fauna Groenlandica. VIII).— T, Ellinger {Medd, om 

 Groenland, Kobenhavn, 1914, 23, 743-51 ; see also Bot. CentraliL, 



1915, 128, 581). A list of all the Protozoa hitherto recorded from 

 the coasts of Greenland and surrounding seas, including Flagellates and 

 Peridiniege. The Flagellates are all chromatophore-bearing forms, and 

 number sixteen, but not all of them are valid species. The Peridinieae 

 recorded are fifty-six, some of which are open to criticism. The paper 

 is a compilation of scattered literature on the subject. E. S. G. 



Trachelomonas inconstans : a New Flagellate. — Nellie Carter 

 (New Phytologist, 1919, 18, 118-19, fig.). A description of a new 

 species of Trachelomonas, collected in May, 1918, with other Flagellates 

 in a small rain-water pool at Sutton Park, in Warwickshire. The 

 distinctive feature of the organism is the prominent nodule or spiny 

 excrescence at the posterior end. The whole case or sheath also is 

 strongly impregnated with iron. The living plasm is densely green, 

 with a bright red stigma and several contractile vacuoles ; and a long 

 flagellum protrudes from the neck of the case. A. G. 



Cytology of Two Species of Characiopsis. — Nellie Carter {New 

 Pkytologist, 1919, 18, 177-86, figs.).- An account of the structure 

 of two species of Characiopsis — G. Naegelii (A. Br.) Lemm., and 0. 

 saccata, a new species — found on dead oak-leaves in a rain-water pool at 

 Sutton Park, in Warwickshire. There is a remarkable difference in the 

 internal structure of the two species, as is shown in detail by the author. 

 They were also compared closely with Gharacium angustum and G. 

 Sieboldii, with the result that the only constant differences to be notice- 

 able between the two genera were the presence of pyrenoids and 

 starch in Gharacium, and their entire absence from Gharaciopsis, where 

 the food-reserve is in the form of oil. A. G. 



Vertical Distribution of Plankton in the Lake of Geneva. — 

 L. Baudin {^BuU. Soc. Vamloise Sci. Nat., 1919, 52, 275-316). Th6 

 area investigated was a cove by the small town of Rolle, facing 

 south ; and the time occupied by the investigation was from the spring 

 of 1913 to the autumn of 1916. Owing to initial difficulties, and later 

 to the war, the sequence of operations was so disturbed that the results 

 here given are mainly based on the work of December, 1915, January 

 and March, 1916, for the winter months, and May, June and August, 



1916, for the summer. Details of each period are given, illustrated by 

 tables. As a rule, during the summer the number of individuals 

 diminishes gradually. The author discusses in detail various facts 

 relating to the vertical and horizontal distribution of the different 

 groups, and finally gives the following conclusions : — (1) The use of the 

 pump is indispensable for acquiring a clear idea of the vertical distribu- 

 tion of the plankton. (2) From the plankton point of view, the regime 

 of the water in winter is essentially different from that in summer. 

 (3) In winter the plankton is fairly uniformly distributed from the 

 surface to the base, or at least to the point where the seasonal variations 

 are perceptible. • (4) In summer the plankton is confined to the surface 



