302 SUMMARY OF CURRENT RESEARCHES RELATING TO 



Contributions to a Knowledge of the Fresh-water Algse of 

 Croatia. — Y. Vouk {Prirodoslov. istraziva?ij. Hrvafske i Slavonije. Zagreb, 

 1919, 14, 145-50, 1 pi. ; see also Izvjesca {Bulletin) Mat.-Prir. Razreda 

 Zagreb, 1919, Sv. 11, 12, 57-60). The first note is entitled '' Lemanea 

 fucina Atk. and other algte from the neighbourhood of Gospic." 

 L.fucina was found growing in rushing water under a weir in the river 

 Lika. It did not correspond wholly with Sirodot's diagnosis, having 

 three to five or even seven to eight antheridial papilla, as against two 

 to three. Other differences are the abrupt narrowing of the stem at 

 the base and the extraordinarily copious branching of the almost pilif orm 

 branches. It generally begins first in the middle of the fruiting portion 

 of the thallus. Atkinson's diagnosis fitted the Lika plant better. 

 Unf ortunatelv no Chantransia stase was found. L. fucina is a well-marked 

 reikophyte, i.e. an inhabitant of rushing Avater. The reikophytic adapta- 

 tion is shown in the rich branching and in the copious development of 

 carpospores. The entire inner surface of the hollow fruiting thallus is 

 filled with sporangia which remain sheltered till maturity. After their 

 escape through the torn thallus, the large number of spores increases 

 the chance of survival. Another well-marked character of this reiko- 

 phyte is the unusually well-developed power of vegetative regeneration 

 of portions of the thallus. A short list of other species from the vicinity 

 of Gospic is given, including Hgdrurus fcBtidus f . penicillatus. The 

 second note in this paper records the finding of Thorea ramosissima 

 Bory in Croatia, in the brook Toplica near Sv. Jana, by Jaska. Small 

 plants were growing at the exit of the thermal spring from the basin, 

 while in the brook itself quantities of it were growing, reaching a length 

 of a metre. The nearest locality to this record is in the Danube near 

 Beograd. The Toplica material showed the short assimilators which 

 have been called monospores. E. S. G. 



On the Ferruginous Cyanophycese. — Y. Youk {Rad Jugoslav. AJcad. 

 Zagreb, 1920, 223, 12S-H7). Records a new species of Lyngbya, 

 L. molischi, which has abundant deposits of ferric oxide in its sheaths- 

 It was found in the thermal waters of Daruvar. This discovery led to 

 an examination of preserved material of about fifty difl^erent species of 

 Cyanophycete, only eight of which gave a positive iron reaction. These 

 all had pectinous sheatbs and mucilaginous strata, but did not include 

 any species of Oxcillatoria. All pi'cserved material from the thermal 

 waters of Topusko and Daruvar reacted pusitively with potassium ferro- 

 cyanide ; but the author regards this infiltration of iron as a post-mortem 

 process. L. molischi alone shows marked deposits of iron in its sheaths. 

 Of all other algte investigated only three species have given the positive 

 reaction, Phormidium papyraceum f. lutescens, P. antliariwn, and 

 P. tinctorium. In all these the ferruginous deposit was in the mucila- 

 ginous layers and not in the pectinous sheaths. The distribution of 

 iron was irregular. Most was found in P. tinctorium. The author regards 

 them as belonging to Gaidukov's second group of iron-organisms, which 

 deposit iron only on the surface, and calls them "optional iron-organisms." 

 Lynrjbya molischi and probably also L. ferruginea, L. ochracea and 

 H ydrocoleus ferrugiiius belong to the first group of " obligatory" iron- 



