286 DISCOVERY REPORTS 



Cells united to form curved chains. Valves elliptical in outline. Valve surface flat, 

 concave or convex. Angles produced to form stout truncate processes or bosses, one 

 produced a little more than the other, so that the cell has a cuneate aspect in girdle view. 

 Valve surface covered with puncta which are arranged in curved lines radiating from an 

 eccentric spine. Connective zone sometimes wide, composed of numerous intercalary 

 bands. The cells vary very considerably in the degree of silicification. In some speci- 

 mens the cells were small and coarse, puncta large and irregularly arranged, while in the 

 extreme southern waters the cells were very weakly siliceous and the puncta very dif- 

 ficult to see. Chromatophores : several small rounded bodies. Polar axis 30-66^. 



A characteristic Antarctic diatom, widely distributed throughout the Southern Ocean. 

 Very common around South Georgia and to the south of the Cape of Good Hope. 



Observed at Sts. 300-305, 365, 368, 378, 379, 380, 381, 382, 386, 427, 433, 436, 440, 

 461, 463, 475, 480, 481, 482, 501, 505-513, 542, 544, 570, 576, 577, 580; WS 469, 474, 

 481, 55°> 55 1 . 552A, 709, 710; MS 86. 



Eucampia cornuta (Cleve) Grunow ex Van Heurck. (PI. XII, fig. 10.) 



Van Heurck, 1880-5, pi. 956, fig. 5. 



Hustedt, 1930, p. 774, fig. 452. 



Karsten, 1928, p. 237, fig. 280. 



Molleria cornuta Cleve, 1873, p. 7, pi. 1, fig. 6. 



Cells somewhat rectangular in girdle view, often curved, solitary or united to form 

 chains. Valves narrow, elliptical, finely striate. The poles of the valve are strongly pro- 

 duced. Processes, truncate. The connective zone is elongated, and possesses many 

 annular segments, segments striate. Chromatophores: numerous cocciform bodies. 

 Apical axis 30-44^ ; pervalvar axis 80-140^. 



An oceanic species, having a wide distribution in tropical and subtropical seas. It 

 occurred frequently around the coast of Africa, particularly on the eastern side. 



Observed at Sts. 425, 428, 436, 439, 440, 1570, 1572, 1574, 1581, 1584, 1586. 



Eucampia zoodiacus Ehrenberg. (PI. XII, fig. 7.) 



Ehrenberg, 1840 a, p. 151, pi. 4, fig. 8. 

 Hustedt, 1930, p. 772, fig. 451. 

 Lebour, 1930, p. 187, fig. 147. 



Cells united to form flattened chains, often spirally curved. Valves face to face, 

 narrow, elliptic-linear, minutely punctate. Valve surface depressed in the centre, leaving 

 the processes flattened. In girdle view the depressions appear as large apertures varying 

 in shape from narrowly lanceolate to broadly elliptical. Valve surface furnished with one 

 small eccentric spine. Girdle composed of a number of narrow annular segments. 

 Chromatophores: numerous rounded bodies. Polar axis 30-96/^; pervalvar axis 40/A. 



A neritic species, commonly distributed throughout northern European waters and 

 the Mediterranean. It was observed at one station only off the east coast of Africa. 



Observed at St. 1373. 



