104 BULLETIN 100, UNITED STATES NATIONAL MUSEUM 



NAVICULA (ALLOIONEIS) GRUENDLERI Cleve 



See N. inexacta, new name. 



NAVICULA HAMULIFERA Grunow 



(Cleve, Nav. Diat., vol. 1, p. 154, pi. 3, figs. 16-19.) 



NAVICULA HENNEDYI W. Smith 



(Gregory, Glenshira Diat., pi. 5, fig. 3; Donkin. Brit. Diat., pi. 2, fig. 3; Schmidt, 

 Atlas, pi. 3, fig. 18; Van Heurck, Synopsis, pi. 9, fig. 14.) 



As above mentioned, the including here of N. clavata Gregory is 

 unwarranted. This common species occurs in both Campeche Bay 

 and the Philippine Islands. 



NAVICULA HOSPES A. Schmidt 



(Schmidt, Atlas, pi. 8, fig. 32.) 



So far as I know, this unique diatom has been found elsewhere only 

 at Samoa. 



NAVICULA IMITANS, new species 



Plate 22, figs. 5-6 



Valve broadly oval with produced, rounded apices; marked with 

 closely set rows of small well-rounded beads, the rows diagonal to the 

 longitudinal axis, barely so at the middle of the valve, progressively 

 more so toward the apices; the beading interrupted by a double-lyrate 

 or H -shaped hyaline design similar to that of the type form of N. lyra 

 Ehrenberg, its four horns wide apart, slightly connivant toward thei r 

 ends, stopping short of the sides of the valve ; the two halves of the 

 r haphe straight except at the apical ends, where they are sharply twice 

 bent or hooked, the ends at the center approaching closely and 

 enlarged. 



Length, 0.090-0.168; width, 0.053-0.083; 14.3 lines in 0.01 mm. 



This diatom is abundant in the Philippine Islands and is very 

 uniform in appearance. It resembles wide varieties of N. lyra Ehren- 

 berg and of N. approxirnata Greville. Naviculae with a double- 

 lyrate design occur in great variety. It would be a disadvantage to 

 attempt their classification under a single specific name. 



Type.— Cat. No. 43647, U.S.N.M. 



NAVICULA INDICA Greville 



(Micro. Journ., 1862, pi. 9, fig. 13.) 



De Toni (Syl. Alg., p. 105) makes this N. macraei Kabenhorst on 

 the basis of a too meager description, and without illustration, in 

 Rabenhorst's Flora Europaea Algarum, volume 1, page 226. With- 

 out much question, it should rather be taken to be a variety of N. 

 clavata Gregory, where the hyaline H-shaped area is charged with a 

 heavy granulation. If this view were taken the name of Gregory 

 would have precedence, 1856. 



