78 BULLETIN 100, UNITED STATES NATIONAL MUSEUM 



GLYPHODESMIS ACUS, new species 



Plate 16, figs. 2-3 



Valve long, narrowly prismatic, tapering at first rapidly from the 

 broadened angular middle portion and then more slowly to the blunt 

 apices, the two halves frequently (not always) unequal in length; 

 crossed by strictly transverse, fine beaded lines, which are bisected 

 by a delicate longitudinal median line, extending the entire length of 

 the valve; the central knob or elevation is small and difficult to see, 

 except in side view, because of its not being hyaline nor surrounded 

 by a hyaline area, but marked with the same beaded crosslines which 

 cover the rest of the valve; the two apical knobs are small but evi- 

 dent; in side (girdle) view the frustule is seen to be about six times 

 as long as its width, the faces of two attached frustules being well 

 separated, except where they touch at the apices and at the center 

 by their terminal and median knobs. 



Length, 0.042-0.068; width, 0.010-0.012; lines, 16-17 in 0.01 mm. 



This species might be easily mistaken for a Fragilaria, if seen with 

 a low magnification and only in its face view. Its true generic posi- 

 tion is however made clear by the side aspect, which is therefore here 

 illustrated. Its minute size makes it easily overlooked, but in many 

 of the Philippine Islands gatherings it is quite abundant, especially in 

 one from Jolo Jolo. 



Type— Cat. No. 43624, U.S.N.M. 



GLYPHODESMIS ELONGATA Cleve and Grove 



(Le Diat., 1891, pi. 8, figs. 12-14.) 



The original came from the near-by Macassar Straits. 



GLYPHODESMIS MARGARITACEA Castracane 



(Castracane, Chall. Exp., p. 44, pi. 18, fig. 10; Schmidt, Atlas, pi. 209, figs 

 51-53.) 



See remarks under genus above. 



Genus GRAMMATOPHORA Ehrenberg 



GRAMMATOPHORA FUNDATA, new species 



Plate 16, figs. 4-5 



Valve flat, but appearing to be crossed by heavy undulations, about 

 12 to 14, caused by underlying tortuous septa; sides parallel and 

 straight; ends round, generally same width, sometimes slightly 

 swollen; surface of the valve covered with coarsely cut quincunx 

 markings; medial line obscure or absent; median area oval, its 

 longer axis transverse and reaching to the sides; in side (girdle) 

 view the frustule is seen to be three to three and one-half times as 

 long as broad; the tortuous septa are massive, evenly undulating and 

 terminate near the center in heavy blunt, triangular ends. 



