SYSTEMATIC ACCOUNT 339 



Grammatophora serpentina Ehrenberg. 

 Ehrenberg, 1844, p. 203. 



Found associated with the preceding species. In no respect do the specimens differ 

 from those commonly found in Europe. The cells differ from those of the previous 

 species in that they possess no median inflation, and that they taper slightly towards the 

 extremities. Valves linear, apices rounded. Striae upon the valve surface a little more 

 vigorous than those of G. kerguelensis. Apical axis of cell 80-1 20/x. 



A neritic and littoral species widely spread throughout temperate coastal waters. 



Observed at St. WS481. 



Genus Rhabdonema Kiitzing 



Kutzing, 1844 



Mann (1907, p. 321) pointed out that Rhabdonema was truly synonymous with the 

 genus Tessella Ehrenberg (1838, p. 202), and that the type-species of the latter, Tessella 

 catena, was identical with Rhabdonema arcuatum Kutzing. This was recognized also by 

 Kutzing. In Diatoms of the Albatross Voyages (1907) Mann restored Tessella, but 

 abandoned it later in his Marine Diatoms of the Philippine Islands (1925). The name 

 Rhabdonema is used here in the sense in which Kutzing used it, until it is conserved. 



Rhabdonema adriaticum Kutzing. (PI. XI, fig. 2.) 



Kutzing, 1844, p. 126, pi. 18, fig. 7. 

 Lebour, 1930, p. 202, fig. 164. 



Cells quadrangular in zonal aspect, united to form chains. Valves linear-lanceolate in 

 outline. Apices rounded, very slightly swollen, plain. Pseudoraphe narrow, linear. 

 Valve surface covered with parallel striae arranged either side of the pseudoraphe; 

 striae slightly divergent towards the apices. Connective zone very strongly developed, 

 striate, furnished with numerous septa. Chromatophores : numerous irregular or 

 stellate bodies. Apical axis of cell 100-130/x. 



A littoral form common around the shores of all European countries, the Atlantic, 

 and the Pacific coasts. 



Observed at Sts. WS 622, 623. 



Genus Entopyla Ehrenberg 

 Ehrenberg, 1848 



Most authors give 1841 as the date of publication of this genus, citing a figure, 

 namely 96 of section 1, plate 1, of Ehrenberg 's work on the microscopic organisms of 

 North and South America, which appeared in the Abhandlnng der Akademie der Wissen- 

 schaft zu Berlin (1841) 1843. This however is quite in error. Fig. gb of the above men- 

 tioned plate was described as a fragment of Snrirella aus traits, and it was upon this 

 species that Ehrenberg created the genus Entopyla in 1848. 



