172 P. T. CLEVE, SYNOPSIS OF THE NAVICULOID DIATOMS. 



5. C. cruciata Pant. (1886). — Outline elliptical. L. O, os to 0,o46; B. 0,o2 to 0,027 mm. 

 Upper V. with finely striate margin (15 strise in 0, 01 mm.). Äxial area lanceolate, in the middle 

 dilated to a fascia. Strise 8 to 9 in 0, 01 mm. composed of large, distant piincta, arranged in 

 longitudinal, undiilating rows. — Pant. I p. 31 Pl. XVI f. 148. 



Marine: Ceylon (Le Tourneur Cell.)! Hungary, fossil (Pant). 



6. C. gibbocalyx Brun. (1891). — Outline broadly elliptic-lanceolate. Ends subcuneate. 

 L. 0,032 to 0,04.') ; Bi 0,024 to 0, 032 mm. Upper V. with narrow, linear-lanceolate axial area. 

 Strise 7 in 0, 01 mm., composed of few, large puncta, and ending at the margin in large costiB 

 forming a rim. Lower V. with straight median line, ending in the conical and elevated extremities. 

 Central pores distant. Axial area narrow. Central area rounded, large. Strite. abont 9 in 0, 01 

 mm., radiate thronghout, composed of distinct puncta, 8 to 12 in 0, 01 mm., becoming smaller 

 towards the median line and arranged in longitudinal rows, more or less parallel with the margin. 

 Margin of the valve finely striate (strise 16 to 22 in O.oi mm.). — I), espéces nouv. p. 17 Pl. 

 XVIII f. 4. A. S. Atl. CXC f. 35? CXCIII f. 54 to 55. 



Marine: Zanzibar (Brun), Manilla (Deby Coll.)! Mauritius (Brun Coll.)! Gralapagos Islands! 

 West Indies, Tortola! 



This is a very remarkable and isolated species. Both valves have not been seen in contact, 

 so that it is somewhat doubtful whether the xipper valve, which has some reserablance to Cocc. 

 Sctitellum, really corresponds to the valve here described as the lower. 



7. C. gråta A. S. (1894). — Outline elliptic-lanceolate. L. 0, 04 to 0,o6; B. 0,o3 to 0,o44 

 mm. Upper V. with a broad, lanceolate axial area. Striée 10 to 11 in 0, 01 mm. composed oi 

 distinct puncta, about 16 in 0, 01 mm. Lower V. with an annulus of rudimentary loculi, about 5 

 in 0,01 mm. Median line straight, reaching to the margin. Strite 15 in 0, 01 mm. radiate, finely 

 punctate, becoming fainter towards the median line. — Pl. II f. 30, 31. A. S. Atl. CXC f. 36. 

 CXCII f. 65 



Marine: Campeachy Bay! Mediterranean Sea! Gi"ip in Norway! 



C. andesitica Pant. (III Pl. X f. 170; 1893) appears to be akin to this species or to 

 C. dirupta. 



8. C. distans (Grbg. 1857?) A. S. 1874. — Outline elliptical to elliptic-lanceolate. L. 0,05 

 to 0,07; B. 0,03 to 0,04 mm Upper V. with narrow, lanceolate axial area. Puncta elongated, 

 forming slightly radiate transverse (about 7 in 0, 01 mm.) and iindulating longitudinal rows (about 

 4 in 0,01 mm.). Lower V. nnknown. — N. S. I). Pl. III f. 22, 23 (1874). Atl. CXCIII f. 29, 36, 

 40. C. dist. forma minima Perag. D. de Villefranche p. 37 Pl. II f. 13. 



Marine: Arctic America! Sea of Kära! North Sea! Mediterranean Sea! Madagascarl Java! 

 Florida! Campeachy Bay! 



C. distans Grbg. (M. J. III p. 39 Pl. IV f. 9; 1855) is a mere variety of C. Scutellum. 

 C. distans Greg. (T. M. J. 1857 Vol. V Pl. 1 f. 25 and D. of Clyde p. 490 Pl. IX f. 23) seems not 

 to difPer from C. gramdata Greg. The species I consider as C. distans has been figured by A. Schmidt, 

 but is a small variety, nanied by Peragalo var. minima. Schmidt figures one speeimen with median 

 line and central nodule, but this fig. certainly represents an entire frustule. I have seen in a 

 gathering from Java an entire frustule, but the coarse structure of the upper valve prevented me 

 from examiiiiiig the lower one, which seems to be very delicate. C. lamprosticta Greg. (T. M. S. V. 

 p. 69 Pl. I f. 28, 1857) represents either this species or a form of Cocc. Scutellum. 



9. C. Disciilus SciiuM. (1864). — Upper V. broadly elliptical. L. 0,02; B. 0,oi5 mm. Axial 

 area lanceolate. Stritu 8 in 0, 01 mm. composed of two to four large elongated puncta. Lower V. 

 unknown. — Navicula Disculus Schum. Preuss. D. I Nachtr. p. 21 f. 23. 



Fre.sh or slightly brackisli water: Domblitten and Spirding, Prussia, fossil! Sweden, (baltic 

 deposits from the Ancylus-cpo(;h)! 



