MARINE DIATOMS OF THE PHILIPPINE ISLANDS 157 



very narrow except close to the row of outer plates where there is a 

 short thickening obscurely marked with a double row of beads; no 

 median area; polar areas evident. 



Long diameter, 0.117-0.194; short diameter, 0.066-0.112 mm. 



S. lata W. Smith (Smith, Brit. Diat., pi. 9, fig. 61), S. macraeana 

 Greville (Micro. Journ., 1862, pi. 2, fig. 1) and the somewhat unrelated 

 figure in Peragllo's Diatomees de la France, plate 61, figure 6, called 

 S. lata, var. macraeana; also S. mexicana A. Schmidt (Atlas, pi. 4, figs. 

 10-12), S. japonica A. Schmidt (Atlas, pi. 4, fig. 15), S. pacijica A. 

 Schmidt (Atlas, pi. 4, fig. 19), together with the above, form a group 

 of related species that show a more or less close similarity. The pres- 

 ent species is practically without alae, there is no trace of central area, 

 the marginal plates from which the costae arise are lozenge-shaped 

 and sharply pointed at their outer ends. It is therefore unsatisfac- 

 tory to call it a variety of any of the foregoing. It is rather plentiful 

 in several of the Philippine Islands dredgings. 



Type.— Cat. No. 43689, U.S.N.M. 



SURIRELLA PATENS A. Schmidt 



(Schmidt, Atias, pi. 4, figs. 16-17; pi. 56, figs. 10-11; Janisch, Gaz. Exp., pi. 

 21, figs. 28-29. ) 



This is rather close to S. ceylanensis Leuduger-Fortmorel. 



SURIRELLA RECEDENS A. Schmidt 



(Schmidt, Atlas, pi. 19, figs. 2-4; pi. 24, fig. 28.) 



SURIRELLA RENIFORMIS Grunow 



(Schmidt, Atlas, pi. 309, fig. 9; Grunow. Diat. Hond., pi. 194, figs. 8-9a-6.) 



Grunow first named this Plagiodiscus martensianus (fig. 8 above) 

 and P. nervatus (fig. 9a-b) in his Honduras Diatoms (Micro. Journ., 

 1S77). It is common in the Philippine Islands and, curiously, was 

 given the name reniformis by me before I discovered Grunow's iden- 

 tification. It occurs also in the Hawaiian Islands at Hilo, at Laysan 

 Island, etc. 



SURIRELLA SCHLEINITZII Janisch 



(Janisch, Gaz. Exp., pi. 19, fig. 7; Schmidt, Atlas, pi. 206, figs. 18-19.) 



The report on the diatoms of the Gazelle Expedition was issued by 

 C. Janisch in sixteen photographic plates, accompanied by a text nam- 

 ing only part of the figures. It was distributed to quite a number of 

 diatomists in either 188S or 1SS9. Grunow refers to Janisch's report 

 on the Gazelle diatoms in the Botanisches Centralblatt of 188S, but 

 Rattray in his Revision of Coscinodwcus states that it was " read June 

 17th, 1889." It is included in diatom bibliography by De Toni, Rat- 

 tray, and others and is extensively referred to in diatom literature. 



