172 



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



5. C. cruciiita Pant. (1886). — Outline elliptical. L. (),o3 to 0,u.46; B. 0,02 to 0,027 nun. 

 Upper V. with finely striate mai'gin (15 stricE in 0,01 mm.). Axial area lanceolate, in the middle 

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

 longitudinal, undulating rows. — Pant. 1 p. 31 PL XVI f. 148. 



Marine: Ceylon (Le Tourueur Coll.)! Hungary, fossil (Pant). 



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

 L. (),u,32 to (),04r); B. 0,u24 to 0,032 mm. Upper V. with narrow, linear-lanceolate axial area. 

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

 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. Strife about 9 in 0,oi 

 mm., radiate throughout, composed of distinct puncta, 8 to 12 in 0,oi mm., becoming smaller 

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

 Margin of tlie valve finely striate (strite 16 to 22 in O.oi mm.). — I), especes nouv. p. 17 PI. 

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



Marine: Zanzibar (Brun), Manilla (Deby Coll.)! Mauritius (Brun Coll.)! (lalapagos 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 upper valve, which has some resemblance to Cocc. 

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



7. C. grata A. S. (1894). — Outline elliiitic-lanceolate. L. 0,0-1 to 0,o6; B. 0,o3 to 0,o44 

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

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

 in 0,0 1 mm. Median line straight, reaching to the margin. Stride 15 in 0,ui mm. radiate, finely 

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

 CXCII f. 65 



Marine: Campeachy Bay! Mediterranean Sea! Grip in Norway! 



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

 C. dirupta. 



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

 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,oi mm.) and undulating longitudinal rows (about 

 4 in 0,01 mm.). Lower V. unknown. — N. S. D. PI. Ill 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 Kara! North Sea! Mediterranean Sea! Madagascar' Java! 

 Florida! Campeachy Bay! 



C. distans GreCx. (M. J. Ill p. 39 PL IV f. 9; 1855) is a mere variety of C. Scntellum. 

 0. distans Greg. (T. M. J. 1857 Vol. V PL I f. 25 and D. of Clyde p. 490 PL IX f. 23) seems not 

 to differ from 6'. grannlata Greg. The species I consider as C. distans has been figured by A. Scumidt, 

 Init is a small variety, named by Peragalo var. minima. Schmidt figures one specimen 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 examining 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. Scntellum. 



9. (J. Disculus ScHUM. (1S64). — Upper V. broadly elliptical. L. 0,02; B. 0,oi.'-. mm. Axial 

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

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



Fresh or .slightly brackish water: Domblitten and Spirding, Prussia, fossil! Sweden, (baltic 

 de])osits from the An(ylus-C])och)! 



