124 BOTANICAL RESULTS OF THE SCOTTISH NATIONAL ANTARCTIC EXPEDITION. 



Samples 1-3 (yellow snow !), fairly common. 



Probably nearly allied to T. reticularis (Reinsch), Hansg. For full consideration, 

 see p. 116. 



12. TROCHISCIA NIVALIS, Lagerh., Ber. Deutsch. Bot. Ges., x., 1892, p. 530, and 

 pi. xxviii., fig. 23 (PI. L, fig. 29). 



Sample 11, rare. 



The individuals were rather smaller than those described by Lagerheim (diam. 

 cell. = 10 fj.), but as in his form covered with very numerous minute spines; one (or 

 more ?) pyrenoids were visible in every case. There appear to be several chloroplasts. 



13. TROCHISCIA PACHYDERMA (Reinsch), Hansg., Hedwigia, 1888, p. 128; Reinsch, 

 Uber Acanthococcus, Ber. Deutsch. Bot. Ges., 1886, p. 240, tat), xi., figs. 8-9. 



Samples 10 and 11, fairly common. 



SCENEDESMACEsE (seusu Oltmanns). 



14. UOCYSTIS LACUSTRIS, Chad., Bull. Herbier Boissier, v., 1897, p. 296, and 

 pi. x., fig. 1-7. 



Forma nivalis, n. f. (PI. I., figs. 27, 28). 



Poli cellularum rotundati vel acuti ; in cellula aliquantum adipis fiavi. Long. cell. = 

 13-15 M; lat. cell. = 9-10 M. 



Samples 1-3 (yellow snow !), rare. 



This form has been fully considered on pp. 112-113. 



15. OOCYSTIS SOLITARIA, With: in Wittrock et Nordstedt, " Alg. aquse dulc. exsicc," 

 No. 244, Bot. Notiser, 1879, p. 24 and fig. 



Sample 11, rare. 



Cells ellipsoidal in shape, with rounded ends ; membrane moderately thick, with 

 apparently two layers, slightly thicker at the two ends of the cell ; cells generally 

 solitary, but now and again to the number of about eight within a mother-cell. Fat 

 generally present in the cell-contents. Length of cells = 16-20 M ; width = 13 M. 



16. CHODATELLA BREVISPINA, n. sp. (PI. I., figs. 25, 26 ; PI. II., phots. 3, 5. Ch). 

 Cellulse ellipsoidese plus miuusve complauatee setis brevibus quje non amplius bis 



crassitudine membranse cellules exstaut per totam superficiem externam confertee ; setse 

 plerumque tenues et angustse, interdum paulo crassiores, sequilonga3 ; inter ea quse 

 cellula continet semper est adeps, plerumque abundans, ssepe similis duobus globis in 

 utroque fine cellulse. Long. cell. = 17-20 ^ ; lat. cell. = 10-15 M. 



Samples 1 and 3 (yellow snow !), common ; isolated in sample 10. 



This species differs from all hitherto described species of Chodatella in having very 

 short spines, which cover the surface uniformly. A full consideration will be found 

 on pp. 111-112. 



