36 p. T. CLEVE, SYNOPSIS OF THE NAVICULOID DIATOMS. 



(3. P. galapageiise Cl. N. Sj). — V. scarcely sigmoid, lanceolate, tapering from the middle 

 to the snbacute ends. L. 0,1?; B. 0,o4 6 mm. Median line straight, central. T^ansv. and obi. striae 

 >Vn ill <^>,oi mm. Angle about 90°. — PI. IV f. 1(5. 



Marine: Galapagos Islands! 



Tliis form is nearly akin to F. nicoharicum, but differs l)y. the median strijc, which are not 

 more distant than the terminal. 



7. P. Eudoii Pant. (1880). — V. scarcely sigmoid, lancecdate, tapering from the middle to 

 the subacute ends. L. 0,2 8; B. 0,o5 mm. Median line straight, central. Transv. and obi. striae 

 1^,., (on the fig. in Pant.). Ends of the valve with a lunate marking. — Pant. I p. 30 PI. XXI 

 f. 190. Per. Ill f. 21. 



Marine: Hungary, fossil (Pant.). 



8. P. iiieobaricuHi Grun. (1807). — V. scarcely sigmoid, lanceolate, gradually tapering from 

 the middle to the subacute ends. L. 0,i4; B. 0,03.5 to 0,o4 mm. Median line central, straight. 

 Obli(|ue strict more distant in tlie middle. Transverse striie coarser than the oblique (15 to 16 in 

 0,0 1 mm. according to GrRUN.). Transv. and obi. striae -•'/io in 0,oi mm. (Perag.). Median oblique 

 stria' 20, terminal 24 in 0,5 1 mm. (Perag.). — P. valulum var.? nicob. (tRUN. Novara p. 101 PI. I. 

 A. f. 20. F. nicohar. (tRun. A. D. p. 51. Per. p. 10 PI. IV f. 9. F. (iffim; rar. nicoh. Grun. in 

 V. H. Syn. Suppl. PI. C. f. 34. 



Marine: Nankoori, fossil (Grun.), Belgium (V. H.). 



Var. Sagiita Brun. and Temp. (1889). — V. rhombic-lanceolate. L. 0,15 to 0,175; B. 0,03 

 to 0,03 6 mm. Median oblique striae 12 to 14, terminal 17 to 20 in 0,oi mm. (Brun.). — F. Sa;/ift(i 

 Brun. and Temp. IJ. foss. du Japon p. 49 PI. IX f. 19. Per. IV f. 13. 



Marine: Japan, foss. (Brun.). 



Var. hamnlifcra Brun. (1889). — V. rhomboidal. L. 0,o9 to 0,12; B. 0,o25 to 0,o3 mm. 

 Median line central, straiglit, curved at the ends. Median oblique strite more distant than the 

 terminal stria; which are at an acuter angle. Transv. and obi. striae ^'/ai (^^ ^^ ^^ Brun) in 0,01 

 mm. — P. hmnnlifermn Brun. D. foss. du Japon p. 48 PI. IX f 5. Per. p. 13 PI. V f. 31. ]\ 

 nicoh. var. indica Per. IV f. 12. 



Marine: Japan (Brun.), China (Deby Coll.)! Sumatra (Per). 



The original P. nicobaricum greatly resembles my P. (/aJaj^cif/cnsr, but according to Grunow 

 (A. D.) it is nearly akin to P. affitw antl the fig. in V. H. Syn. evidently represents a form akin 

 to F. Normnnii. This is also the case with P. Sdf/itta Brun. As to P. hanmliferum I ha\-e not 

 seen Brun's original specimens, and his description of the striation is incomplete. In Deby's collec- 

 tion I have seen a specimen closely resembling P. liamulifenuH and evidently nearly akin to P. 

 Normanii. It closely resembles P. nicoh. rar. indica Per. It seems probable tbat the original P. nico- 

 haricum may be identical with F. galapagense, and that P. nicoh. Grun. in V. H. Syn., Per, gra- 

 duates into P. Normanii. 



9. P. naviculaceum Br]i;b. (1854). — V. not, or slightly sigmoid, lanceolate, acute. L. 0,o8 

 0,1; B. 0,0 15 to 0,02 mm. Median line strongly sigmoid. Median oblique striae more distant than 

 the terminal, which are at an acuter angle. Transv. and obi. striae '7i6) 'Vi7» ^7i8- — ^- 'W^^c. Bri5b. 

 Mem. de la Soc. du Cherb. 1854 f. 7. Grun. A. D. p. 51. V. H. Syn. Suppl. PI. C. f. 35. P. 

 transversale W. Sm. B. D. II p. 96 (1856). P. japonicum Castr. I). Challenger Ex. XXIX f. 14. 



Marine: North Sea! Mediterranean! Ceylon! Java! Labuan! 



Forma minuta. L. — 0,o5; B. 0,015 mm. Transv. and obi. striae "■^Vzo- 



Marine: Sumatra! Bab el Mandeb. ! 



10. P. liniigai'iciini Brun. and Cl. (1889). — V. broadly rhomboidal, slightly sigmoid, acute. 

 L. 0,1 to 0,13; B. 0,045 to 0,0c. mm. Median line strongly .sigmoid. Central nodule orbicular. 

 Median oblique striae forming a larger angle than the terminal, which are more acute. Transv. 



