50 P. T. CLKVE, SYNTOPSIS OF TRR NAVICULOID DIATOMS 



J Axial arei 



,._ 1 Axial area broad C. aupergradata Beun 



narrow or indistinet 6G. 



rea orbicniar 67. 



06. < — — qnadrate 68. 



[ Ceutral area 



— — indistinet 70. 



,.„ I Valve narrow C. blanda A. S. 



\ — broad, almost liexagonal C. quadriseriata Cl. a. Geun. 



„„ J Longitadinal lines marginal C. Camphellii Pet. 



' \ — — median 69. 



„( I Longitndinal lines rather narrow C. PowclKi Lewis. 



^' \ — — — broad C. amica Cl. a. Geun. 



„_ ( StriiE about 21 in 0,oi mm C. venusta Pant. 



■ 1 — .5 to 10 — 71. 



f Strise .5 in 0,01 mm C. Zanardiniana Grun. 



71. •! — 8 — C. Wittii Grun. 



I — 12 — C. sejuncta A. S. 



1. C. lepidula Grun. (1880). — V. narrow, linear, with broad, ronnded ends. L. 0,02; 

 B. 0,ooG mm. Axial area indi.stinct; central small, orbicular. Striffi parallel, 27 to 30 in 0, 01 mm. 

 Longitndinal lines marginal. — Nat. Icp. GrRUN. in V. H. Syn. p. 108 Pl. XIV f. 42. 



Fresh water: Belgium (V. H.). 



2. C. bacillaris GreCt. (1856). — V. linear, -with ronnded ends. L. 0,023 to 0,05; B. 0,005 

 to 0,00 G mm. Axial area very narrow; central area small, sometimes unilaterally dilated to a fascia. 

 Striifi 20 to 22 in 0,oi mm. almost parallel. — Nar. hacilhvis Greg. M. J. IV Pl. I f. 2-4. V. H. 

 Syn. Pl. XII f. 27. 



Fre,sh water: Scotland (Greg.), Illinois (Grove CoU.)! 



ii 



3. C. fasciata Lagstr. (1873). — V. linear to linear-laneeolate, Avith broad ronnded ends. 

 L. 0.02.3 to 0,037; B. 0,00!) to 0,008 mm. Axial area indistinet or narrow. Central area a broad 

 fascia. Longitndinal lines indistinet, strite parallel 24 to 26 in 0, 01 mm. — Nav. fasciafa Lägst. 

 Spitsb. D. p. 34 Pl. II f. 11. V. H. Syn. Pl. XII f. 34. Nav. fonficola Grun. V. H.' Syn. 

 Pl. XII f. 32 (1880). Nav. fontinalis Grun. V. H. Syn. p. 103 Pl. XII f. 33. Nav. BaciUum var. 

 inconsfantissima Grun. in V. H. Syn. Pl. XII f. 28. Nav. Lacunarum Grun. V. H. Syn. Pl. XII 

 f. 31. Stauroneis Bacillmn Grun. Verli. 1863 p. 155 Pl. IV f. 16. Nav. (niolaris var.?) ab!/s.9i)vica 

 Grun. in Martelli Flornia Bogosensis p. 152 Pl. I f. 4 (1886). 



Fresh or slightly brackish water: Spitsb.! Iceland! Scotland! Sweden! Finland! Belginm! 

 Abyssinia (Grun.). X. Zealand! N. America, Hoboken, X. Jers! Dakota! Brazil! Ecuador! Argentina! 



Tliis little form bas some resemblance to some small Pinnularise of the section Parallelistriatse, 

 so that Grunow (V. H. Syn. Pl. XII f. 34 text) con.siders the form from Spitsbergen to be a Pinnn- 

 laria. I tbink it is more akin to Nav. BaciUum. Tlie longitndinal lines are not distinct in most 

 specimens, bnt I liave seen snch lines faintly on specimens from slightly brackish water at Piteå 

 (Gnlf of Bothnia), which I am unable to distingnish from the larger form, named bj- Grunow Nav. 

 Lacmnirum. As I can see no diiference betweeu Nav. fasciata and Grunows Nav. fo)iticoJa, Nav. 

 fonfinaIi.'i and Nav. Lacunarum I have nnited them. 



A probably allied form is Nav. UrcguH Hérib. a. Perag. (D. d'Auvergne p. 119 Pl. IV f. 17 

 and var. JanceoJ/ifa f. 18) fossil in the Anvergne Depo.sits. The valve is more lanceolate, in L. 0,o28 

 to 0.03.T mm. The strite are stated to be 12 to 15 in O.oi mm. Sfauro)iei.'f acutiuscula of the same 

 author (p. 78 Pl. III f 20) with 20 strite in 0,oi mm. also fossil from Anvergne maj- be a 

 form of Coloneis fasciafa, or possibly of Sfauroiwis {Plcurosfaiiron) parvrda Grun., which I am 

 unable to decide withont original specimens. 



4. C. Beccariaiia Grun. (1886). — V. gibbous in the middle. with broad capitate ends. L. 

 0,o2G to 0,074; B. 0,007 mm. Axial area narrow, central area a broad, transverse fascia. Striae 



