24 P. T. CLRVE, SYNOPSIS OF THE NAVICULOID DIATOMS. 



„ j Valve thin 4.. 



\ — solid T. solidula Cl. 



j Frustule in zonal view elliptical T. aniarctica Cl. 



■ \ — — — rectangular T. tnembranacea Cl. 



^ I Valve nearly flat T. longn Cl. 



' ' \ — elevated (5. 



J Wing close to the keel T. npproximata Cl. 



'■ \ — not — 7. 



_ j Central area indistinct or small T. Lepidoptera Greg. 



distinct — T. maxima Greg. 



{ 



II. Plagiatropis Pfitzer, median line exeentric; keels of the valve.s in contrary directions. 

 Striae coarse and di-stant T. Zebra Cl. 



j Striae coar 

 \ — closi 

 Striae crossed by blank, longitudinal Itands T. seriata Cl. 



lose — 2 



^- { - not - - - 3. 



„ I Valve not striate along the margin 4. 



' \ — striate to the margin f). 



, J Transverse striae about 15 in O.oi mm T. japonica Cl. 



\ — — — 19 — T. semistriata Grun. 



J. j Frustule constricted in the middle G. 



' \ — not or slightly 9. 



J Wing or longitudinal band instinct T. samoevfiis Grun. 



— — distinct 7. 



road T. siimharensis Cl. 



narrow 8, 



I L. about 0,08 mm T. gihhcndn Grun. 



\ — 0,14 mm T. chinensin Cl. 



„ I Valve narrow, almost linear 10. 



{ 



{Valve bro 

 — nar 



\ — broader, lanceolate 11 



i;:; 



.J . ..... 0,2 to 0,27 mm T. elegant Greg. 



' about 0,oe mm T. pusilln Greg. 



L. 0,00 mm T. Van Henrckii Grun. 



L. 0,09 to 0,2 mm 12. 



Longitudinal band, if present, not interrupted 13. 



— — interrupted in the middle T. lata Cl. 



ae slightly finer than the transverse T. Kinkeriana Cl. 



— much — — T. vitrea W. Sm. 



,„ j Longitudinal stri 



III. Amphoropsis Grun., median line exeentric; keels of the valves turned in the same 

 directions. 



Keels without coarse ribs T. recta Greg. 



{ 



with — — T. concerta Lewis. 



1. T. iiutarctica Grun. (1878). — Frnstnle membranaceons, elliptical in outline. L. 0,i9 to 0,24; 

 B. 0,0 6 to 0,0 8 mm. Central area small, staxtriform (the central nodule probably being a little 

 transversely dilated). Transverse and longitudinal striae 21 (16 to 18 Brun) in 0,oi mm., the me- 

 dian transverse striai more distant than the others. — Amphipr.? antarctica Grun. in Cl. M. D. 

 No. 125. Navicula Challcngcri Grun. A. D. p. 64 (1880). Stuuroneis glacialis Castrac. Voy. Challeng. 

 D., p. 25. PI. XXVII f. il, 1886? Amphipr. fragilis Temp. u. Brun. D. fossiles du j'apon, p. 14. 

 PI. IX f. 14 (1889). 



Marine, pelagic: Antarctic Ocean! Japan, fossil (Brun.). 



2. T. uiembraiiacca C'l. (1873). Frustule membranaceous, rectangular, very .slightly con- 

 stricted, with rounded angles. L. 0,2.^) to 0,.3r>; B. 0,o7 to 0,125 mm. Central area indistinct. 

 Transverse strise 20 to 24, longitudinal 30 to 32 in O.oi mm. — Amphiprorn niemhranacea Cl. D. 

 of the Sea of Java p. 12, PI. II, f. 18. 



Marine, pelagic: Java! Sumbava (Kinker (^oll.)! Colon (H^hy (Joll.)! 



