THK FRESH-WATER CYANOPHYCEÆ OP ICELAND 



285 



Lyngbya stagnina Kiitz. 

 Lemmermann 1905 p. 146. 

 Tab. phyc. I, tab. 87, lig. V. 



S. Icel. Knararnes ^/s 1905 (H. J.)! 

 Area: Eur. 



Lemmermann 1910 p. 139. Kutzing 



Fig. 6. Lyngbya stagnina 

 Kutz. (X600). 



Gomont referred the present species to Lyngbya æstiiarii which it 

 also closely resembles (Monogr. II p. 128). Gomont, however, had no 

 original specimen at his disposal; Lemmermann fl905 p. 146), on the 

 other hånd, succeeded, on the basis of an investigation of a specimen 

 collected by Kutzing in Fusina near Venice, in proving that Lyngbya 

 stagnina is not identical with L. æstuarii from 

 which it is especially distinguished by the faet 

 that the sheath is coloured intensely blue with 

 chlor-zinc-iodine. In the sample from Knarar- 

 nes I have now found a Lyngbya that, at all 

 essential points, agrees with Lemmermann's de- 

 scription of L. stagnina Kiitz. However, a few^ 

 deviations occur, the apex of the trichome, e. g., 

 being briefly tapering (Kiitzing's figure seems to 

 me to point in the same direction) and provided 

 with a broader or narrower calyptra which is 

 slightly convex. The material was preserved in 

 alcohol and perhaps in consequence there ap- 

 peared constrictions between the cells in some 

 of the trichomes (fig. 6, a). The trichomes were 

 8—10 // in diameter, the cells 1.5—2 jn in length 

 (somewhat shorter than stated by Lemmermann). 

 In the Icelandic sample Lyngbya lutea, Spirnlina 

 subsalsa and Nodularia Harveyana were also present. I therefore pre- 

 sume that It has grown either in brackish or in salt water. The loca- 

 hty of Kutzmgs onginal specimens also seems to indicate that it is a 

 brackish-w^ater form, Fusma bemg a small town at the lagoon of Venice. 



Lyngbya lutea (Ag.) Gom. 



Gomont, Monogr. II p. 141, pi. 3, figs. 12-13. 



S. W. Icel. Knararnes -/s 1905 (H. J.)! 

 Area: Eur., Afr., Am., Færoes. 



t.„ ^^^^''''^Vr "'^ ;'"".-^**i°" ^«"e between the salt and the fresh water 

 together with L. æstnarn, L. slagnina as well as Spirnlina snbsaha. 



Lyngbya Martensiana Menegh. 



Nr. 1^'2T"'' ^^°"'^'" " ^' ^^^' P'- "^" "^- ^^- ^^''^''- '' Nordst. Alg. exsicc. 



N. Icel. Akureyri; hot spring ^^/e 1903 ro. P)i 

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



It is difficult on the basis of statements in the literature to form 

 species. It has been found m hot springs (43° Bohlin 1901 p 74) as 



