114 BOTANICAL RESULTS OF THE SCOTTISH NATIONAL ANTARCTIC EXPEDITION. 



own ; the shape of the cells is mostly spherical, but sometimes slightly oval, and a kind 

 of colourless beak is often to be seen on one side. In a few cases, especially after 

 staining with iodine or gentian violet, it appeared as though there were a pair of short 

 cilia arising from this beak and attached close together. All attempts to obtain clearer 

 preparations were, however, unsuccessful, and the presence of cilia in the Antarctic 

 form must therefore remain doubtful. I have been able to make out only very little 

 of the cell-contents ; a small round body (probably a pyrenoid) can generally be 

 detected, and there was commonly a small colourless area beneath the beak at the front 

 end of the cell, but the chloroplast could not be properly deciphered. The cell-contents 

 frequently contain starch, but fat was generally completely absent in these colonies. 

 Apart from the normal colonies just described, two other kinds of colonies were 

 observed. Firstly, such as showed many or all of the cells in process of bipartition ; 

 and, secondly, colonies in which most or all of the cells had their contents divided up 

 into a considerable number of smaller cells (generally about eight). The latter have a 

 very characteristic appearance (fig. 1, G), and are on the whole commoner than the 

 other two types. The small cells in these colonies are often distinctly ovoid and 

 pointed at one end. They are generally more or less filled with the all-pervading fat, 

 which appears to arise in the cells of the normal colony at the time of their division ; for 

 whereas the cells of the normal colony are, as above mentioned, quite devoid of fat, 

 occasional colonies are to be found in which the cells contain considerable quantities of 

 fat, and in these one or other of the cells are always in process of division. 



The genus Sphserocystis was described by Chodat 1 in 1897; subsequently Wille 2 

 endeavoured to identify S. schroeteri, Chod., with Glceococcus mucosus, A. Br., 3 a view 

 that was opposed by Chodat in a later paper, 4 mainly on the grounds of the marked 

 difference in size of the colonies in the two genera and the absence of cilia in his form. 

 There seems, however, to be some evidence for the synonymy of the two genera, 

 although the species are not necessarily identical ; for the present they are probably 

 best kept distinct. Chodat failed to observe the cilia on the cells embedded in 

 mucilage, stating definitely "pas de pseudo-cils " ; Wille does not say whether he 

 observed them, although, as he makes no negative statement, it is to be presumed that 

 he did. 6 Wille 6 describes as especially characteristic a clear space having the shape 



1 Chodat, foe. cit. 



2 Wille, " Algologische Notizen, xii., Uber Glceococcus mucosus, A. Br.," Nyt Magazin f. Naturvidenskab, xli., 1903, 

 pp. 163-166. 



3 Cf. A. Braun, Betrachtungen uber die Erscheimmg der Verjiinguiig in der Natur, Leipzig, 1851, p. 169 (Bug. trans, 

 by A. Henfrey, 1853, p. 159); also A. Braun, "Uber Chytridium, etc.," Abhandl. Kgl. Ak. d. Wiss., Berlin, 1855, 

 pi. v., figs. 5-20. 



4 " Quelques points de nomenclature algologique : I. tiphserocystis, Cliod. ou Glcnococcus, A. Braun ? " Bull. Herbier 

 Boissier, 2nd ser., iv., 1904, p. 233. 



s There is also no mention of the cilia in Wille's description of Glceococcus in Engler-Prantl, Die Natiirl, Pflan- 

 zenfam., Nachtr. z. 1 Teil, 2 Abteil., Leipzig, 1909, p. 18. 



6 Wille, " Algologische Notizen, xii.," foe. cit., p. 1 65. This space is here, probably as a result of a misprint, described 

 as occurring in the back part of the cell ("im hinteren Teile der Zelle"). Cf. however fig. 5, A (p. 19), in Engler- 

 I'rantl, he. cit. 



