KUNGL. SV. VET. AKADEMIENS HANDLINGAR. BAND 61. N:0 Ii. 



25 



Mesogloea (Ag.) J. Ag. 



M. falklandica nov. spec. — Fig. 11 c, 13 a. 



Fröns in speciminibus nostris ad 7 cm älta, sat crassa, ad 3 mm diam., valde 

 mucosa, va^e et parum ramosa ramis simplicibus, e stratis tribus composita, strato 

 centrali filis longitudinalibus 15—30 [x crassis, cellulis diametro 4 — 6-plo longioribus, 

 strato pericentrali valido, e filis angulo subrecto exeuntibus, di-trichotomis, cellulis 

 anguste cylindricis, 10—15 *x diam., saepe basi conspicue inflatis nec non hyphas 

 longissimas emittentibus, strato peripherico ex assimilatoribus valde coloratis, 

 longissimis, moniliformibus, sat densis, articulis subglobosis — breviter cylindricis, 

 12—15 ;j. crassis, sporangiis ovato-clavatis, 80 — 105x30 — 45 jx nec non pilis tenuibus 

 circ. 10 [i latis composito. Gametangia non visa. 



Fig. 11. a — b Castagnen Zostcrce : a longitudinal filaments with bundles of assimilators, etc, b part of section 

 through frond. C Mesogloea falklandica: horizontal filaments with assimilators and sporangia. All X L20. 



Falkland Islands: Westpoint Island, tide-pools in the litoral region, 

 very scarce (St. 8, 6. 12. 07, sp.). — As far as I am aware, nothing like this has 

 ever been collected in Southern waters. The generic position must remain a point 

 of discussion until a monographic treatment of the entire group appears. The long 

 external filaments give to the plant almost the habit of a Myriocladia, but in this 

 genus a considerable portion of the assimilators protrude through the mucus, what 

 is not the case in Mesogloea. To judge from the description and figures of Suringar, 

 111. Alg. du Japon, M . falklandica is nearly related to M. crassa Sur. from Japan, 

 but this has shorter central cells, not much longer than the diameter, which is 

 38 — 77 |J. ; the assimilators are thinner, measuring only 3.8 — 7,7 p- across, and less 

 constricted at the septa. Suringar compared M. crassa with Myriocladia sciurus 

 Harv. and Mesogloea natalensis Kutz. and proposed to unite those three species 

 under one genus. Tinocladia Sur. 



K. Sv. Vet. Akad. Handl. Band 61. N:o 11. 4 



