FRESHWATER ALOJ3. 29 



35. LYNGBYA scorn * sp. n. 

 (PI. II., figs. 91-93.) 



Fills augustis, plerumque valde tortuosis, iuterdum subrectis, stratum in superficie 

 Phormidii formantibus ; vaginis priino tcuuibus hyaliuis, demum modicc ineras.satis 

 extus rugosis cum particnlis mimcrosis adluurentibus, non lamellatis ; trichomatibus 

 cum cellula apieali acuta couica, non capitati.s aut attenuates, plerumque modice inter 

 cellulas constrictis ; cellulis tain lougis quam latis vel paulo longioribus, plerumque 

 cjtoplasmate homogeueo, dissepimentis indistinctis, sed interdum cum granulis dense 

 aggregatis in utraque parte dissepimentarum : calyptra uulla. 



Diam. ill. = 3 '4-5 fj. ; diam. trich. = 2'G-3 p. 



Hab Granite Harbour, January 20th, 1902. 



This species should lie compared with /,//)////'//< kutzingi Schmidle, and its 

 variety ilixf/iicfit (Xordst.) Lemni. ( = L. Kiilrfilix West). It differs from these forms in 

 the thickened rugose sheath of older filaments, in the acutely conical apical cell, the 

 slight constriction between the cells and the occasional granulation of the dissepiments. 

 The adhesion of small particles to the rough surface of older sheaths is a marked 

 characteristic, as the bulk of the filaments showed it. 



Var. MINOR var. nov. (PI. 11., figs. 9-1-96). 



Filis angustioribus, plerumque valde tortuosis ; vaginis tcnuibus hyalinis ; 

 trichomatibus cum cellula apicali acuta conica, interdum paulo attenuatis, modice inter 

 cellulas constrictis ; cellulis tarn lougis quam latis vel paulo longioribus, contcntu 

 homogeneo. 



Diam. til. = 2 - 5-2' 7 ju. ; diam. trich. = 1' 5-1 '8 /A. 



J/n/i. Gap pond, Winter Harbour, February 20th, L 904 (forming a stratum on 

 Phormidium). 



This variety differs chiefly from the type in its smaller dimensions and in the 

 apparent absence of thickening of the sheath in older filaments. The cell-contents 

 were in all cases homogeneous. 



36. LYNGBYA LAGEKHKIMI. 

 (PL II., tigs. 74-78.) 



Lyr/bya Iti'irrlii'iiiiii (Mnb.) (ioiimnt. torn, fit., pp. II 7-1 is, PI. IV.. fi^s. 0, 7 (SpiracoUua 

 vi^ui, iss'.l, p. :J!L', Tab. in, figs. 1, I'). 



Diam. fil. = 3-3 '5 \t. ; diam. tridi. = 2-3 /-t. 



Jftilt. Freshwater pond in eskers upon LC6, lialfxvay between Black Island and 

 Brown Island, January :!rd, 1903. 



* This species is named after Captain Scott, C.V.O., the leader of the British National Antarctic Expedition 



[and of the British Antarctic Expedition, 1910]. 



