ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 301 



springs in Daruvar are principally considered. Notes are also given on 

 the thermal waters of Sv. Helena near Samobor ; Lesee near Generalski 

 stol ; and Podsused near Zagreb. Three springs of Topusko were 

 examined, the temperature of the water varying from 52-57" C. The 

 springs in the open meadows showed a surface encrusted with alg£e, and 

 layers of membranous green alga at the bottom of the basin. They 

 were both composed of two species, Mastigodadus kiminosus Cohn and 

 Phnrmidium laminosuin var. accernhscens, a new variety founded on the 

 absence of reaction with chlorzinc-iodine. Species of OaciUatoria and 

 Pliormidium, etc., occurred according to the lower degrees of temperature 

 in the waste channel, but no general marked effect in the vegetation of 

 the thermal area was observed which could be traced to the action of 

 the raised ground temperature. The Daruvar springs are next described. 

 Several of them show a remarkable dissimilarity of their algal flora. 

 Lynghya molischi was the principal constituent of one spring. The 

 three other thermal waters and their respective floras are briefly discussed. 

 In the original Czecho-slovak edition of this paper the Cyanophyceae 

 formations in the hitherto investigated euthermal waters are set forth 

 in tabular form, together with the temperature limits of each species. 

 The individuality of the various localities is there demonstrated, although 

 certain species, Mastigodadus la^ninosus, Phormidium laminosuin, Hypheo- 

 thrix thermalis, OsciJlatoria cortiana, and 0. Okenii are more widely 

 distributed. Desmids are entirely lacking, and Diatoms are very rare. 

 Chlorophyceffi barely reach to a temperature of 35° C, though in Asia 

 and America they are found in hotter waters. The Czecho-slovak hot 

 springs are almost entirely characterized by pure Cyanophycere-forma- 

 tions, E. 8. (t. 



Chservations on Gloeotaenium Loitlesbergerianum Hansg. — 

 G. HuBER {Att. Soc. Elvetica >Sci. Nat. lOO" Congresso, Lugano, 

 1919. Part II. Aarau, 1920, p. 111). Matel'ial found in Canton Glarus 

 by the author in 1907 constituted the first record for Switzerland. An 

 examination of the morphology and development gives the following 

 results : — The " concrements " formed in the coenobial membrane and the 

 polar chambers are composed of calcium carbonate, a fact which was 

 the more difficult to establish since the contact with acid, either organic 

 or inorganic, produced no effervescence. This was owing to the 

 carl)onate being finely broken up and enclosed on all sides by colloids. 

 G. loitlesbergerianum was found in stages of one, two, three and four 

 cells, the four-celled tetrahedral coenobia being especially noteworthy. A 

 newly observed condition is the so-called Hemicoenobium, which must be 

 regarded as a completely developed two-celled coenobium which has arisen 

 through subsequent division. The girdle-shaped " concrements " 

 probably serve principally to keep the cells in position : any physiological 

 role they may play has yet to be discovered. Reproduction is carried 

 on exclusively by daughter-cells, which escape by dehiscence. The 

 very early foundation and development of the girdle-concrements and 

 of the polar chambers was observed and followed. A new variety, var. 

 irregulare, is described. The author records further the occurrence of 

 G. loitlesbergerianum in the Beetsee in N.E. Switzerland. E. S. G. 



Y 



