MARINE DIATOMS OF THE PHILIPPINE ISLANDS 75 



DONKINIA CARINATA (Donkin) Ralfs 



(Pritchard, Inf., p. 921, pi. 8, fig 49; H. L. Smith, Types, No. 143; Peragallo, 

 Pleuro., pi. 9, fig. 6.) 



DONKINIA RETICULATA Norman 



(Greville, Diat., So. Pacific, pi. 3, figs. 13-14; Peragallo, Pleuro., pi. 9, fig. 2.) 



Greville's figure is ideal and Peragallo's poor. 



ECHINODISCUS, new genus 



Valve circular, slightly convex to the elevated rim, then turned 

 vertically downward to form deep sides perpendicular to the central 

 portion of the valve, and finally expanded into a narrow hyaline 

 flange, where the valve joins the girdle; central portion of the valve 

 irregular, covered with circular splotches united by veriform lines 

 into larger or smaller patches, thickly (but irregularly) scattered 

 over the surface; the elevated rim and the vertical sides of the valve 

 closely covered with a fringe of irregularly shaped prickles, and at 

 one point on the rim a broad lunate or hemispherical process. 



ECHTNODiSCUS VERMICULATUS, new species 



Plate 16. fig. 1 



Characters those of the genus. 



Diameter 0.169 mm.; depth of vertical side 0.01 mm. 



It is probable that the two unnamed figures in Schmidt's Atlas 

 plate 164, figure 6 and plate 202, figure 3, from the near-by locality 

 of Jeddo, Japan, are examples of the same genus. If so, the vermic- 

 ulate character of the markings here represented can be looked upon 

 as a somewhat abnormal phase of the more regular radiating pattern 

 shown in Schmidt's two figures. In that case, the specific name 

 here given should apply only to the spines or prickles covering th e 

 rim and sides. It is evident that none of these forms can be referred 

 to the genus Stepliano pyxis, as Schmidt suggests. A much closer, 

 affinity exists between this and Endictya, to which further specimens 

 may prove it belongs. The above-mentioned lunate process on the rim, 

 in that view of the case, would only be an aberrant occurrence con- 

 fined to those clearly fantastic specimens. I have, however, thought 

 best to represent this interesting diatom exactly as it is, leaving its 

 validity subject to the foregoing remarks. 



Type.— Cat. No. 43622, U.S.N.M. 



Genus ENDICTYA Ehernberg 



ENDICTYA MARGARITIFERA, new species 



Plate 15, figs. 9-10 



Surface of the valve barely concave to the rim, which is elevated 

 above the inner portion and sharply turned downward to form the deep 

 vertical sides, to the lower edge of which the girdle is attached; both 



