192 P. T. CLEVE, SYNOPSIS OF THE NAVICULOin niATOMS. 



Äsymmetrical forms. 



Var. californica Cl. — V. linear-lanceolate, obtuse. L. 0,17 to 0,22; B. 0,(j.i to 0, 03.') mm. 

 Axial area liiiear, unilateral. Alveoli close, dispcsed in irregular, longitudinal ro\v.«, and .slightl}' 

 radiate, transverse rows, (> to 7 in 0,01 mm. 



Marine, fossil: Japan (Brun Coll.)! San Pedro (Kinker Coll.)! S:ta Monica Cal. (Deby Coll.)l 



Var. derasa Cl. — V. linear, obtuse. L. 0,22; B. 0,02.3 mm. Axial area broad and irregu- 

 lar, unilateral. Central area a broad fascia, reaching to the margin. Alveoli clo.«e, forming 

 oblique rows and slightly radiate, at the ends parallel, rows, 7 in 0,oi mm. 



Marine: Madagascar (Kinker Coll.)! 



Var. intermedia Gtrun. (1876). — V. narrow lanceolate to elliptic-linear. L. 0,i to 0,19; 

 B. 0,019 to 0,0 2 6 mm. Axial area narrow, unilateral. Alveoli forming longitudinal or oblique 

 rows, and transverse, slightly radiate rows, 7 to 9 in O.oi mm. — Nav. asprra var. internt. Grux. 



A. S. Atl. XL VIII f. 14. Franz Josephs Land D. Pl. I f. 20. JVav. aspera rar. hungarica Pant. 

 II p. 42 Pl. X f. 180 (1889). 



Marine: Greenland! Spitzbergen! Franz Josephs Land (Grun.), Finmark! Sea of Kära! Cape 

 Deshneff! Ndrth Sea! Fossil: St. Peter, Hungary! Briinn! Sendai, Japan! 



Var. oblonga Bail (1854). — V. linear, with subcuneate ends, and frequently with a median 

 gibbosity. L. 0,i7 to 0,22; B. 0,04 to 0, 05 mm. Axial area narrow: linear, unilateral. Alveoli 

 close, in oblique and transverse rows, the latter slightly radiate, 7 to 10 in 0, 01 mm. — Stauroptera 

 oblonga Bail Smiths. Contr. 1854 p. 10 f. 17. St. oblonga? A. S. Atl. Pl. XLVIII f. 16. Stanro- 

 neis oblonga Castr. Voy. Challenger p. 24 Pl. XX f. 7 to 11. 



Marine: Sydney! Kerguelens Land! South America, fossil! 



Var. rhombica Cl. — V. rhomboid. L. 0,12; B. 0,o5 5 mm. Ends acute. Median line ex- 

 centric. Axial area linear, unilateral. Central area large. Costce near the margin transverse, 9 

 in 0,01 mm. Alveoli arranged in oblique rows, crossing each others in an angle of about 80% 6 

 in 0,0 1 mm. 



Marine: Galapagos Island! 



Var. perobliqua Cl. — V. linear, gradually tapering towards the obtuse ends. L. O, ids; 



B. 0,02 mm. Median line very excentric. Axial area indistinct. Alveoli arranged in obliqe and 

 transverse rows, the latter 8 to 9 in 0,oi m. m. — Pl. III f. 37. 



Marine: Macassar Straits (Grove Coll.)! 



Var. Amjihora, Brun (1891). — V. strongly äsymmetrical. L. 0, 09 to 0,i4 mm. Axial area 

 irregular, unilateral. Central area small. Alveoli arranged in oblique and tran.sverse rows, the 

 latter 6 in 0, 01 mm. — Nav. Amphora Brun De espéces n. p. 32 Pl. XV f. 3. 



Marine: Port au Prince and King Georgs Souud (Brun). 



Var. Schmidfiana Grun. (1876). — Lanceolate, somewhat gibbous in the middle, obtuse. 

 L. 0,08 to 0,11; B. about 0,oi7 mm. Axial area linear, unilateral. Alveoli distant, disposed in 2 

 to 3 longitudinal rows and in transverse rows, 9 to 12 in 0, 01 mm. — Nav. Schm. A. S. Atl. 

 XLVIII f. 19, 20. 



Marine: Campeachy Bay! Galapagos Islands! 



2. T.(?) tiinixdiila Grun. (1860). — V. gibbous in tlie middle and with broad, truncate ends. 

 L. 0,025; B. 0,011 mm. Axial area indistinct; central area a broad fascia, reaching the margin, 

 where it is dilated. Rows of alveoli radiate, 13 in 0,oi mm. — Stauroneis tumid. Grun. Verh. 

 1860 p. 566 Pl. VI f. 10. 



Marine: Red Sea (Grun.). 



I have not seen this form, whicli, to judge from Grunow's description, seems to belong to 

 Tracliyneis. 



3. T. Clepsydra Donk. (1861). — Frustule rectangular, constricted in the middle. V. couvex, 

 linear lanceolate, with obtuse or subtruncate ends. L. 0,i 1 to 0, 13; B. 0, 02 mm. Median line 



