278 DISCOVERY REPORTS 



Biddulphia polymorpha Mangin (1915, p. 27). This name was technically incorrect upon 

 two grounds, firstly, because the name was preoccupied (Biddulphia polymorpha 

 (Grunow) Wolle, 1890) and secondly, that as the group of forms described by Van 

 Heurck merely represented variants of one species, the first name to be applied must 

 be the name adopted. As all the names used by Van Heurck received publication 

 simultaneously, Biddulphia anthropomorpha is used here by virtue of priority of place. 

 Observed at St. WS481. 



Biddulphia regia (Schultze) Ostenfeld. (PI. XII, figs. 2, 3.) 



Ostenfeld, 1908, p. 7, fig. 3. 



Lebour, 1930, p. 175, fig. 135. 



Hustedt, 1930, p. 838, fig. 494. 



Denticella regia Schultze, 1859, p. 21, figs. 11, 12. 



Cells somewhat rectangular in girdle view, broadly elliptic-lanceolate in valve view. 

 The poles of the valves are produced to form narrow processes, which are frequently 

 distinctly capitate. Valve mantle only very slightly curved inwards beneath the processes 

 to meet the girdle, sometimes almost straight. Central area of the valve only slightly 

 raised, often weakly concave, and furnished with two long spines. Spines slightly 

 divergent at first, but bent towards the centre at a distance a little over half of their 

 length. Spines with mucronate ends. Distance between the two spines usually much 

 greater than that between the spines and the processes. Entire surface of the cell covered 

 with fine areolation. Chromatophores : numerous rounded bodies. Polar axis iio/^; 

 pervalvar axis 40-120/x. 



A neritic species, commonly found in the northern hemisphere. It was observed at 

 one station only off the east coast of Africa, below Madagascar. 



Observed at St. 1373. 



Biddulphia striata Karsten. (PI. X, figs. 4, 5.) 



Karsten, 1905, p. 122, pl. 17, figs. 2, 3. 

 Mangin, 1915, p. 22, fig. 1. 



Cells rectangular in girdle view, broadly elliptical in valve view. The poles of the 

 valves are weakly produced into short rounded processes. Central area of the valve 

 slightly convex, furnished with four long, slightly curved spines. Median area of the 

 connective zone, often somewhat inflated. The entire surface of the cell is covered with 

 fine punctation, arranged in quincunx. Chromatophores: numerous stellate bodies. 

 Polar axis 60-84/x : pervalvar axis 120/^. 



One of the most common neritic diatoms around South Georgia, often found in great 

 numbers. It has a very local distribution, and although occasionally found in the 

 Bransfield Strait, particularly in the summer, it is seldom observed in the Weddell or 

 Bellingshausen Seas. It is unlikely that it ever crosses the Antarctic convergence. 



A weakly siliceous form which undergoes considerable variation in shape. It is found 

 living free and also united, the horns or spines of adjacent frustules interlocking, to form 

 short chains of three or four cells. 



