376 SUMMARY OF CURRENT RESEARCHES RELA'JING TO 



Bot. Centralbl., 1918, 137, 22-3). A refutation of Lutze's contention 

 that the presence of Bacillariacese in the western Numburg Stream in 

 North Thiiringen is a proof of a former ice-sheet covering this region. 

 Chsetoceras, Ampliiprora and Bacillaria, " true pelagic species," were said 

 to occur inland only in this stream. In this paper it is shown that all 

 genera are recorded from other inland stations ; as well as Nitzschiella 

 Closterium from the saline waters of Nauheim, and Pleiirosigma and 

 Surirella from other localities. The Bacillariaceae of the western 

 Numburg Stream must be regarded as merely an indication of the saline 

 water from the gypsum mountains. The diatoms have been brought ta 

 the stream from the neighbouring fresh and salt water basins by the 

 various water birds. E. S. G. 



Bacillariaceae of the Streams near Nagyvarad.— J. L. Lacsny 

 {Bot. Kdzlemimjeh, 1916, 15, 101-8, fig. ; Magyarisch, with German 

 resume ; see also Bot. Centralbl., 1918, 137, 5). Three streams flow» 

 through Nagyvdrad, one of which — the Pece— is thermal. The flora of 

 these closely adjacent streams is so different that only one species is 

 common to all three. Three new species are described, and several new 

 varieties. E. S. G. 



Studies of Danish Aerophilous Algse. — J. B. Petersen {Hem. 

 Acad. Roy. Sc. Lettr. Danemark, 1915, 12, 271-379, 4 pis.; see also 

 Bot. Centralbl, 1918, 137, 22). A monograph. Under the title 

 " aerophilous," the author designates those algee which are content to 

 absorb moisture from the atmosphere and can sustain frequent droughts, 

 though not having special resting periods. Prasiola can bear a drought 

 of three weeks ; and certain species of Navicula can exist in earth con- 

 taining little over 5 p.c. of water. The author frequently found 

 terricolous species, especially on fields, rocks and straw roofs. In woods 

 or on dry heathland he found practically none. There are about 25 

 terricolous species, and 9 amphibious. All aerophilous forms are small, 

 but always motile. They belong entirely to the Raphidese. Aerophilous 

 green algte are much commoner. The author discusses Danish associa- 

 tions in detail, and groups them according to their habitat — on earth, 

 rock or roof, under stones or wood, or on trees. Cystococcus humicola, 

 Pleurococcus lobatus, Trentepohlia (even on conifer needles) are very 

 capable of resisting adverse conditions. These species were studied 

 under culture. E. S. G. 



On some New and Rare ChlorophyceaB of the Adriatic. — B. 

 SCHUSSNIG {Sitzungsber. Ksh Akad. Wiss. Wien, 1915, 124, Abt. 1, 

 425-45, 4 pis. ; see also Bot. Centralbl, 1918, 137, 5-6). Three new 

 species of Ulothrix are described, of which two appeared in a culture and 

 have not been observed in the open. One of these, U. longicauda, was 

 found growing among small alg« from the Bay of S. Bartolomeo, 

 and consisted of small tufts of filaments up to 1 cm. long, attached to 

 the substratum by a long acuminate rhizoid. A new genus and species, 

 Sphserosiphon solitarius, is described, also unknown in the open. Inte- 

 resting observations are given on Phseophila tiorideanmi Hauck., which 

 was found by the author both epiphytic and endophytic on many of 

 the larger algffi, as well as on the wall of a culture-glass. The form of 



