THE FRESH-WATER CYANOPHYCEÆ OF ICELAND 277 



Oscillatoria beggiatoifopmis (Grun.) Gom. 

 Gomont, Monogr. II p. 235, pi. VII, fig. 25. 



E. Icel. Nor6fj6r6ur, June 1894 (H. J.)! HalIormsta5ir; spring, temp. 

 3V2 ° "^/e 1914. — S. Icel. Nicolasargjå at Pingvellir; on rocks, temp. 

 SVa*^ ^Vs 1914. 



Area: Hungary. 



This species has only been found twice, viz. in the typical form by 

 Kalclibrenner near Zsivadreda in "aquas acidulas" and by Gutwinski 

 (1909 p. 541) "in uvidis muscosis in silva", but the latter adds "speci- 

 mina recta". The same applies in part to the above-raentioned Icelandic 

 specimens. As to dimensions, apex and granules on eacli side of tlie 

 transverse walls of tlie filaments everything is in accordance with Go- 

 raonts diagnosis; but the trichomes are often straight or more or less 

 irregularl}' curved. However, rather regularly spirally coiled trichomes 

 are also frequently found. 



II. Spirulina Turpin. 



Spirulina subsalsa Orst. 



Gomont, Monogr. II p. 253, pi. VII, fig. 32. 



S. W. Icel. Knararnes Vs 1905 (H. J.)! 

 Area: Cosmopolitan; Greenland. 



This widely distributed species is strictly speaking a marine form, 

 and in the above-mentioned Icelandic locality it was, in faet, also found 

 in Company with other marine or brackish-water species, viz. Lyngbya 

 stagnina Kiitz., Nodularia Harveijana and Lyngbya lutea. 



Spirulina labypinthiformis (Men.) Gom. 

 Gomont, Monogr. II p. 255. 



N. W. Icel. Myri in Dyrafjpr5ur. Moist piaces near the shore ^^/s 

 1895 (C. H. O.)! 



Area: Eur., Afr., S. Am. 



The form in hånd is a Spirulina with a close spiral ca. 2 fi in dia- 

 meter. However, it is not quite excluded that we liere have to do with 

 a thin form of S. subsalsa. The species is stated to have been found 

 partly in brackish water, partly in hot springs. 



III. Phormidium Kiitzing. 



Phormidium fragile Menegh.) Gom. 



Gomont, Monogr. II p. 163, pi. IV, figs. 13-15. 



W. Icel. Reykholt, Snorralaug ^^9 1897 (H. J.)! 

 Area: Eur., Afr., Am., Austr., Antarctic. 



In the above-mentioned sample the trichomes were 1.2 fi in dia- 

 meter, the cells almost quadrate and the apical cell acute-conical corre- 

 sponding to that in Gomont pi. IV, fig. 15. 



The species has previously been found in hot springs, e. g., in Bo- 

 hemia (Hansgirg), in Italy (Meneghini) as well as in California (Borge 



