86 p. T, CLEVE, SYNOPSIS OF THE XAVICULOII) DIATOMS. - 



26. D. subt'iiicta A. S. (1874). — V. slightly constricted in tlie middle, with more or less 

 distinctly cuneate ends. L. O.oe to 0,092; B. 0,o235 to 0,02.') ; at the constr. (),()2 to 0,022 mm. 

 Central nodule large, quadrate; its horns parallel or convergent at the ends. Furrows moderately 

 broad, narrowed at the ends, with faint traces of costse. Costre, 6 to 7 in 0,01 mm., crossed by a 

 longitudinal line. — Nav. siihcincta A. S. N. S. D. PI. II f. 7. Atl. XIII f. 41; LXIX f. 82. 

 Grun. D. Franz Josephs Land p. 56 (4) PI. I f. 38, 39. Nav.' didymu Lagst. Boh. D. f. 4 u. 



Marine: Franz Josephs Land (Grun.), Kara! Finmark! North Sea! Balearic Islands! 

 Adriatic! Madagascar! Monterey, Cal.! Fossil: Aegina (Atl.), Japan (Brun a. Temp.), Maryland 

 (Deby Coll.)! St. Monica (Deby Coll.)! 



27. D. (liscrepans A. S. (1875). — V elliptical. L. 0,o:i; B. O,oii mm. Central nodule 

 broad, (juadrate, its horns divergent at their basis, convergent at the ends. Furrows broad. Costpe 

 II in 0,01 mm., crossed by a longitudinal costa(?). — Nar. discr. A. S. Atl. VILI f. 8. 



Marine: Campeachy Bank (Atl.). 



Unknown to the author. The description is from the iig. in atlas and I am not sure if 

 the longitudinal line across the costff really be a costa. 



'li^. 1). binaria A. S. (1875). — V. slightly constricted, with broad, rounded ends. L. 0,042; 

 B. 0,022; at the constr. 0,02 mm. Central nodule large, quadrate, its horns parallel, approximate. 

 Furrows very broad, not dilated in the middle, with double longitudinal rows of puncta. Costie 

 6 in 0,01 mm. crossed by a longitudinal costa. — Nav. hinaria A. S. Atl. XII f. {}2. 



Marine: Java (Atl.). 



21). D. (lenita A. S. (1881). — V. sligthly constricted. L. 0,nfi; B. 0,o;n; at the constr. 

 0,0a mm. Central nodule large, (juadrate; its horns parallel. Furrows broad, linear. Costs 6 in 

 0,01 mm. crossed by a broad longitudinal costa(?). — Nav. demta A. S. Atl. LXIX f. 34. 



Marine, fossil: St. Monica, Cal. (Atl.). 



Unknown to the author. The fig. in Atl. does not distinctly show if the longitudinal baud 

 is, as here accepted, a costa or a row of ocelli. In the latter case this form may probably be 

 placed near D. Pandura. 



30. D. exemta A. S. (1875). — V. panduriform, with tongue-shaped segments. L. 0,085 

 to 0,136; B. 0,032 to 0,042; at the constr. 0,o2(; to 0,o3 mm. Central nodule quadrate, rather 

 large; its horns parallel. Furrows linear. Costtu 5 in 0,oi mm., crossed by a longitudinal line, 

 on the furrows faint or reduced to puncta. — Nav. exemfu A. S. Atl. XI f. 28, 29. 



Marine: Tamatave (Brun Coll.)! Tahiti! Kerguelens Land (Eae Coll.)! Campeachy Bay! 

 Fossil: Oamaru, New Zealand! S:ta Monica (Deby Coll.)! 



Var.? crahroniformis Grun. (1875). — L. 0,o83; B. 0,o2.'j; at the constr. 0,0 n;. Costa- 6 in 

 0,01 mm. — Nav. crahronif. Atl. XI f. 24. 



Marine: Gulf of Mexico (Atl.). 



Var. d'igredkns Cl. — L. 0,048 to 0,00.^); B. 0.022; at the constr. 0,oi to 0,oi4 mm. Korns 

 somewhat divergent. Costai 8 in 0,oi mm. 



Marine: China (Thum.)! Hungary, fossil (Deby Coll.)! 



31. D. coarctata A. S. (1875). — V. deeply constricted in the middle. L. 0,07 to 0, 1 ; B. 0,026 

 to 0,035; at the constr. 0,oi36 to 0,oi8 mm. Central nodule quadrate, with pai-allel horns. Furrows 

 narrow, linear, with a row of large puncta. Cost;\; 3 — 4 in 0,oi mm., crossed by a longitudinal 

 line. — Nav. cuarcf. A. S. Atl. XI f. 30, 31, 32, LXIX f. 11. 



Marine: Campeachy Bay (Atl.), Cape Horn (Petit), Hungary, fossil (Pant.). 



This is a very suspicious form. The figure recently published by A. Schmidt in Atl. 

 (CLXXIV f. 22) has very much the appearance of being a strongly corroded specimen of I). Crubro 

 var., or of D. Dirhombus, if that form be anything but a small D. Crabro. 



