212 SUMMARY OF CURRENT RESEARCHES RELATING TO 



Fresh-water Diatoms from the Island of Jan Mayen and the East 

 Coast of Greenland.* — J. Brun gives here the result of his examination 

 of the diatoms collected by the Swedish expedition in 1899. The 

 author finds that three-fourths of the Greenland species are found 

 living in the Swiss Alps, and he also notes that the northern forms of 

 diatoms are less variable in size and striatum than those of the high 

 Alps. This comparative stability of form he attributes to the fact that 

 in the polar circle the heat and light of summer are more equable during 

 the time of their season, whereas in the glaciers of the high Alps the 

 growth of diatoms is necessarily affected by the rapid daily alternations 

 of frost and thaw. 



A list of forms follows under the headings of the various localities. 



Capillary Absorptive Action of Diatom Frustules.f— Prof. E. Hitch- 

 cock describes the effect of diatomaceous earth in removing grease 

 from raw wool, which he suggests is due to the capillary absorptive 

 action of the frustules. The deposit employed consisted mostly of 

 Pinnularia, Stauroneis, and other large forms. The cleaning was done 

 by shaking up the wool with the earth in a tin box after application of 

 heat sufficient to melt the fat. 



Perispermum, a new Genus of Corallinaceae. f — From German 

 New Guinea F. Heydrich describes a corallinaceous alga, belonging to 

 the Melobesieae, which he makes the type of a new genus, Perispermum, 

 with the following diagnosis: — Calcareous thallus with basal disc, at- 

 tached to the host by rhizoids which do not penetrate into its tissue, 

 composed of several layers of cells and not segmented ; tetrasporanges 

 and sexual organs in conceptacles ; carpogone and auxiliary cell super- 

 posed terminally on a filament ; the auxiliary cell becomes a gonimoblast 

 with one or more spores ; male organs surrounding the female in the 

 same conceptacle. Special descriptions are given of the habit, the 

 thallus, the tetrasporanges, the germination of the tetraspores, and the 

 male and female organs, in the single species Perispermum hermaphro- 

 ditum. In the hermaphrodite conceptacles the male greatly outnumber 

 the female organs. 



In another paper § Heydrich describes several new tropical species 

 of LithothamniesQ (Lithothamnion and Lithophyllum). The procarps of 

 these species were not seen. 



Contributions to the Flora of Bear Island. || — Miss Astrid Cleve 

 publishes a list of 90 species of diatoms from Bear Island, which shows 

 an increase of 49 species on the list given by Lagerstedt in 1873. The 

 Swedish expedition to that island in 1899 brought back specimens col- 

 lected from many habitats, and though the actual number of specimens 

 was not great, there was considerable variety of specific form. Two 

 new species are described and figured, Pinnularia curta and Achnanthes 

 nodosa, and two new varieties of other species. Short critical remarks 



J 1 * Bihang k. Svenak. Vet.-Akad. Handl., xxvi. pt. 3, No. 18, 22 pp. 

 " t Journ. New York Micr. Soc, xv. (1900) pp. 4-7. 



X Ber. Deutsch. Bot. Ges., xix. (1901) pp. 409-20 (3 figs.). 

 1 § Tom. cit., pp. 403-9. 



|| Bihaug k. Svensk. Vet.-Akad. Handl, xxvi. pt. 3, No. 10 (1900) 25 pp., and 

 No. 11 (1900) 25 pp., 



