MARINE DIATOMS OF THE PHILIPPINE ISLANDS 47 



BIDDULPHIA TRISINUA, new species 



Plate 10, figs. 8-9 



Valve "triangular, trifoliate, the sides deeply concave, the angles 

 broad and blunt ; the threo processes or horns rounded, closely beaded ; 

 across each angle back of the processes is a transverse row of irregularly 

 placed beads; the central part of the valve sparingly dotted with 

 minute beads arrangsd in imperfect crcles; in side (°irdle) view the 

 valve is seen to be flat in the center, the horns vertical and enlarged 

 at the ends; the sides of the valve sparingly and irregularly dotted, 

 like the upper surface; a small groove extends around the valve next 

 to the rim, which is not produced beyond the rest of the valve. 



Diameter of valve (measured from apex to opposite side), 0.101 mm. ; 

 height of valve, 0.090 mm. 



This can hardly be made a variety of Triceratium trisulcum Bailey, 

 its nearest relative (Schmidt, Atlas, pi. 78, figs. 5-8; pi. 94, fig. 5; pi. 112, 

 figs. 11-18). Also compare with T. turriferum Truan and Witt (Diat. 

 Hayti,pl.7, figs. 22-23.) 



Type.— Cat. No. 43599, U.S.N. M. 



BIDDULPHIA TUMESCENS (Castracane) Mann 



(Castracane, Chall. Exp., p. 109, pi. 6, fig. 9.) 



Among the specimens found one resembles T. robertsianum, forma 

 inermis (Schmidt, Atlas, pi. 83, fig. 4), butCastracane's species is valid 

 because the processes are blunt disks, not horns, and the areolation 

 reaches to their bases. De Toni somehow manages to discover a like- 

 ness between this and T. fimbriatum Wallich. 



BIDDULPHIA TUOMEYI (Bailey) Roper 



(Micro. J&urn., 1859, p. 8, pi. 1, figs. 1-2; Schmidt, Atlas, pi. 119, figs. 1-8.) 



Numerous specimens of tlus widely distributed and essentially fos- 

 sil diatom were found and, so far as could be made out, were mem- 

 bers of the now living flora. 



BIDDULPHIA TURGIDA W. Smith 



(Smith, Brit. Diat., p. 50, pi. 62, fig. 384; Van Keurck, Synopsis, pi. 104, figs. 

 1-2.) 



Together with the typical form a somewhat spiny-covered variety 

 was found. 



BIDDULPHIA TURRIGERA, new species 



Plate 11, figs. 1, 2 



Valve triangular, with barely convex sides; horns in the angles tall, 

 erect, with truncated apices, their flat triangular ends having each a 

 central rosette of watery beads; surface of the valve hyaline, flat to 



