MARINE DIATOMS OP THE PHILIPPINE ISLANDS 39 



BIDDULPHIA EXPEDITA Janisch(?) 



(Schmidt, Atlas, pi. 121, fig. 3.) 



As to whether or not this is present in my Philippine Islands 

 material is discussed under BiddulpMa cornigera, new species. 



BIDDULPHIA FAVUS (Ehrenberg) Van Heurck 



(Mikrogeologie, pi. 19, fig. 17; Schmidt, Atlas, pi. 82, figs. 1, 3, 4.) 



This very cosmopolitan diatom, both in recent material and fossil 

 deposits, is represented in the Philippine Islands by the type form 

 and many varieties. A variety that bears the name of Triceratium 

 scitulum Brightwell, is well illustrated in the original figure (Micro. 

 Journ., 1853, pi. 4, fig. 9, and Schmidt, Atlas (pi. 83, figs. 11-13 but 

 not pi. 84, figs. 5-6), the latter being here given the new specific name 

 B. scitula (A. Schmidt) Mann. Schmidt suggests the union of plate 

 83, figures 11-13, with B. favus as a variety, this being the true 

 Brightwell form, but he does not include plate 84, figures 5-6. 



BIDDULPHIA FIMBRIATA (Wallich) Mann 



(Micro. Journ., 18593 , pi. 2, figs. 4-9; Schmidt, Atlas, pi. 82, figs. 6-7.) 



There is a general tendency to unite this with the former species. 

 It is a much more delicate diatom with a different arrangement of 

 the areola tion next to the margin. In fact, the margin, seen in side 

 (girdle) view, is wholly unlike that of B. favus. It may be remarked 

 here that the side view in BiddulpMa is too frequently neglected in 

 descriptions and illustrations, although its significance is most valu- 

 able. This species is not to be confused with Biddulphia jimbriata 

 Greville, which Grunow has rightly transferred to Denticella (Diat 

 F. Jos. Land, p. 6). 



BIDDULPHIA FRACTOSA, new species 



Plate 8, fig. 5; plate 10, fig. 1 



Valve triangular, elevated at the center, its sides slightly or strongly 

 convex; horns at the three angles, stout, tapering, rugose to the tip, 

 their ends even with the margin of the valve; markings of course 

 beading, imperfectly radial in arrangement, loosely scattered over the 

 central part, more compact near the margin; from the sides there 

 run irregularly inward short cracklike depressed lines, two to five 

 on each side, and occasionally a few short isolated ones near the 

 center. 



Diameter (apex to opposite side), 0.056-0.090 mm. 



The general resemblance of this species to BiddulpMa (Triceratium) 



tabellarium Brightwell, especially to its variety called T. vehulosum 



Greville, is apparent. The powerful horns, however, make their 



union impossible. No girdle view of this species was obtainable- 



35035—25 4 



