168 SUMMARY OF CUREENT RESEARCHES RELATING TO 



Undulating Marginal Cilia in a Green Flagellate.— A. Pascher 

 (Archw Froiisfenkunde, 1916, 37, 191-7, 8 text-figs. ; see also Bot. 

 CentralU., 1917, 135, 259-GO). The flagellate in question represents 

 a new genus and species, occurring in the North Sea, Ulochloris oscillans. 

 It is 8-11 /x long, resembling in form a compressed 6'/i/am?/f?omo?2«s ; 

 chromatophore large, pjrenoid wanting, margins delicate, with two cilia, 

 of which one is free. One free cilium each on the back and front ; but 

 in the case of the pairs on the narrow sides, each cilium is connected 

 with the narrow side by a narrow margin, and is only free at the end. 

 The movement is remarkable : the monad swims as easily backwards as 

 forwards, and it can progress in jerks. Reproduction is by longitudinal 

 diyisiou._ _ By the dorsiventral flattening and the peculiar differentiation 

 of the cilia into pairs, the new genus assumed a peculiar development 

 among the Polyblepharidinefe, The origin of the flat discoid chromato- 

 phores from the bowl-shaped type of the Chlamydomonads is shown, with 

 figures. E. S. G. 



Noctiluca miliaris Sur. : A Cytological Investigation. — A. J. C. 

 VAN GooR {Diss. Amsterdam. Amst. V Kasteel v. Aemstel, 1917, 124 ; 

 see also Bot. Centralbl, 1917, 135, 194-6). The author gives a 

 detailed account of his investigation of the cytology of Noctiluca miliaris 

 Sur., which he considers to be of plant nature. He describes methods of 

 treatment, the minute structure of the organism and processes of repro- 

 duction. He believes that if the nuclei of the Dinoflagellates should 

 prove to be polyenergid, this would apply also to the nuclei of Noctilma. 



E. S. G. 



Diatom-Flora of Martin Beck, Yorks.— M. H. Stiles {The 

 Naturalist, 1918, 281-3). This paper is part of the result of an inves- 

 tigation by the Doncaster Scientific Society of the natural history of 

 Martin Beck, between Bawtry and Tickhill, and presents a fairly com- 

 plete record of the Diatom flora of the district. Of the 106 species and 

 varieties, 23 are not included in West's " Alga-Flora of Yorkshire," and 

 40 have not been previously recorded for that division of the West 

 Riding. The most noteworthy records are Navicula americana Ehr.. 

 only known in Great Britain from " Ireland " and " Loch Kinnord," 

 according to Van Heurck. The Martin Beck specimens vary from the 

 type form in being shorter, and, slightly, in the margins of the valves ; 

 :A^. alpina, which is usually found at much higher levels than the 100-ft. 

 elevation of Martin Beck ; X. ignota, shown in Schmidt's Atlas, 43/24, 

 without name, and here named provisionally N. Danensis ; N. pusilla. 



E. S. G. 



Fresh-water Diatoms from Upper Jamtland in Sweden. — C. W. 

 FONTELL {Arkiv for Botanik, 1917, 14, No. 21, 68, 2 pis.). An 

 account of fresh-water diatoms collected near the railway station, 

 Dufed, in Upper Jamtland, during August and September, 1910. About 

 20 samples were taken from the surrounding lakes and rivers, and were 

 found to be very rich in individuals as well as in species ; 375 forms 

 (243 species and 132 varieties), belonging to 37 genera, are recorded. 

 The flora is in the main boreal, and is analyzed in the first ,part of the 



