64 P. T. OLEVE, SYNOPSIS OF THE NAVICULOIO DIATOMS. 



61. C. Castracanei Grun. (1881). — V. broadly linear to lanceolate, with obtuse ends. 

 L. 0,07 to 0,135; B. 0,02 to O, os mm. Median line straight, with small, terminal nodule.s and large 

 quadrate, central nodule. Axial and central areas uniting in a narrow, lanceolate space. Stria; 

 9 to 12 in 0,0 1 mm., slightly radiate thronghout, smooth. Longitudinal lines broad, area-like, 

 median, not nnited with the central area. 



Var. Phili2>]nnarn.m Cl. — V. linear with gradually narrowed ends. L. 0,ii; B. 0,o2 mm. 

 StriBB 12 in 0,oi mm. 



Marina: Manilla (Deby CoU.). 



Var. Fetitiana Grun. (1881). — V. broadly linear, with cnneate ends and parallel margins. 

 L. 0,0 7; B. 0,02 mm. Area crossed by faint strige. Striis 11 in 0,oi mm. — Nar. Fet. frRrx. in 

 Cl. N. R. D, p. 12 Pl. III f. 34. 



Marine: Cebn! 



Var. seychellensis Grdn. Ms. — Like var. Petitiana, Imt without faint strire on the area. 

 Striae 10 in 0,oi mm. 



Marine: Seychelles (Van-Henrck CoU.)! 



Var. caledonica Cl. — V. narrow elliptical. L. 0,i3.-); B. 0,o3 mm. Stria; 10 in O.oi mm. 



Marine: New Caledonia (Kinker Coll.)! 



Var. genuina Cl. — V. lanceolate. L. O, i; B. 0,o3 mm. Strife 9 in 0,oi mm. — Nar. 

 Castracanei Grun. in Cl. N. R. D. p. 12 Pl. III f. 33. 



Marine: Australia (Grnn.). 



G. Castracanei is a large and beautiful form, and is connected by intermediate varieties with 

 C. Powellii. 



62. C? venusta Pant. (1889). — V. linear, with rostrate ends. L. 0,037; B. 0,o9.t mm. 

 Axial area narrow. Central area small, dilated on both sides of the median line to broad lateral 

 areas. Strice 21 to 22,5 in 0,oi mm., parallel, divergent towards the ends. Longitudinal lines mar- 

 ginal. — Nav. venusta Pant. II p. 54 Pl. V f. 81. 



Marine: Hungary, fossil (Pant.). 



I have not seen this species; the description being made from the fignre in Pantocseks 

 work, wliicli shews some likeness to a small C. PoweJUi, with the strife. crossed by a narrow, 

 marginal line. 



63. C. amica Cl. a. Grun. (1881). — V. broad, slightly constricted in the middle, with 

 cnneate ends. L. 0, 07. 'i to 0,095; B. 0, 023 to 0, 03 mm. Axial area verj narrow. Central area 

 large, quadrate, dilated to broad lateral areas on both sides of the median line. Strife 7 to 8 in 

 0,01 mm. smooth, almost parallel. — Nav. amica Cl. a. Grun. in Cl. N. R. I). p. 12 Pl. III f. 37. 



Marine: Tahiti! 



C. amica is remarkable by tlie broad lateral areas, which are also ver}- mueh developped in 

 the following two species. These areas occupy tlie place of the longitudinal lines of the other 

 species of this genus. 



64. C. (juadriseriata Cl. a. Grun. (1881). — V. broad, hexagonal. with parallel margins 

 and large, cuneate ends. Median line with small terminal fissures and incrassate central nodule. 

 L. 0,09 to 0,16; B. 0,035 to 0,047 mm. Axial area narrow. Central area large, orbicular. Striii; 

 7 to 8 in 0,01 mm., slightly radiate at the ends, elsewhere parallel, smooth. Longitudinal areas 

 broad, linear, atteiuiated towards the ends. — Nav. quadriscriata Cl. N. R. D. p. 12 Pl. III f. 32. 

 Nav. duplex Pant. III Pl. XLII f. 579 (1893). 



Marine: Barcelona! Balearic Islands! Gillf of Naples! Levant (Grove CoU.)! 



65. C? kryophila Cl. (1883). — V. elliptie-lanceolate, with cuneate or obtuse ends. 

 L. 0,05 to 0,08; B. 0,0 18 to 0,04 mm. Axial area narrow. Central area small, orbicular, dilated 

 on botli sides of the median line to large. luniite lateral areas, on wliicli faint traces of the stri:e 



