106 i". T. CLEVE, SYNOPSIS OF THfi NAVICtlLOm DIATOMS. 



'-{ 



Ends snbcapitate N. nuda Pant. 



— acute ... 3. 



I Striae about 12 in 0,oi mm. . N. lucida Pant. 

 — — 17 — . . N. Schmidtii Lagst. 

 — — 24 — . . N. Acus Cl. 

 _ _ 30 _ . 4. 



. I Longitudinal striffi closer than the transverse . N. fusiformis Gkun. 



' \ — — more distant N. Frauenfeldii Getjn. 



, ( Ends rostrate ... . . . . N. crassirostris Ghun. 



I — obtuse or truncate 6. 



„ / Terminal fissures in contrary directions 7. 



' \ — — indistinct N. Lineola Grun. 



„ I Striae all parallel N. parallelistriata Pant. 



\ Median striae radiate N heteroflexa Pant. 



1. N. fusiformis Grun. (1877). — V. narrow, lanceolate, gradually tapering from the middle 

 to the acute ends. L. O.iis to 0,15; B. 0,oi mm. Central pores very approximate. Striae trans- 

 verse, 33 in 0,01 mm., longitudinal 36 in 0,oi mm. — BerJceleya Fusidium Grun. Hedw. 1867 p. 17. 

 Amphipleura danica KtJTz Bac. p. 103 PI. XXX f. 38 (1844)? N. fus. Grun. M. J. 1877 p. 178 

 PI. CXCV f. 11. 



Marine: Honduras (Grun.). 



Var. ostrearia Gaillon (1820). — L. 0,063 to 0,073; B. 0,oo6 to 0,oo7 mm. Striae transverse 

 36 in 0,01 mm. — Vibrio ostrearius Gaillon (accord, to Grun.). — Nav. ostrearia Turp. Diet, d'hist. 

 nat. II PI. I f . 2 (accord, to Grun.). N. fusif. v. ostrearia Grun. M. M. J. 1877 p. 178 PL CXCV 

 f. 12. V. H. Syn. PL XIV f. 33. 



Marine: North Sea (West coast of Sweden)! Loire infer. (Grun.), Marseille (Grun.), Triest (Grun.). 



This species lives on oyster-beds and according to Bornbt the oysters become greenish by 

 feeding on this diatom. Living frustules have two chromatophore-plates along the connecting zone. 

 The cell-sap has, especially towards the ends, a peculiar blue colour. 



2. N. Frauenfeldii Grun. (1863). — V. lanceolate. L. 0,i to 0,i6; B. 0,oi9 to 0,025 mm. 

 Central pores very approximate. Transverse striae 29 in 0,oi mm., longitudinal more distant. — 

 Amphipleura Frauenfeldii Grun. Verh. 1863 p. 144 PJ. V f. 3. N. Frauenf. Grun. M. M. J. 1877 p. 179. 



Marine: Indian Ocean (Grun.). 



3. N. nada Pant. (1889). — V. narrow, lanceolate, with subcapitate ends. L. 0,037; B. 0,007 

 mm. Striae not observed. — Pant. II p. 51 PL VI f. 108. 



Brackish water: Hungary, fossil (Pant.). 



This species is unknown to me and the description and figure are not sufficient for diagnosis. 



4. N. Acus Cl. N. Sp. — V. narrow, lanceolate, acute. L. 0,09; B. 0,009 mm. Central 

 pores approximate. Terminal fissures elongated. Axial and central areas indistinct. Striae 24 to 

 25 in 0,01 mm., equidistant, in the middle slightly radiate, elsewhere transverse, or nearly so — 

 PL ni f. 29, 30. 



Marine: Balearic Islands! 



As N. Acus Cl. 1880 (A. D.) is the same as N. inornata Grun. the name Acus majy be used 

 for this form, which diff'ers from N. fusoides Grun. (1880) by the absence of longitudinal lines and 

 by- its indistinct area. 



5. N. Schmidtii Lagst. (1876). — V. narrow, lanceolate, with somewhat obtuse ends:. 

 L. 0,06 to 0,074; B. 0,009 to 0,011 mm. Central pores approximate. Striae about 17 in 0,oi mm., 

 transverse. — N. (without name) A. S. N. S. D. PL III f. 7, 8 (1874). N. Schm. Ldt. Boh. D. p. 45^ 



Marine: Bohuslan (Ldt). 



I do not know this species, which seems doubtful. The fig. in A. S. is not sufficient, and 

 the description of Lagerstedt may belong to some form of Nav. (Schizonema) ramosissima. The 



