106 p. T. CLKVK, SYNOPSIS OF, THE NAVICULolD DIATOMS. ~ 



No axial nor central area on the dorsal side. Longitudinal line closely approximate to the median 

 line. Dorsal stride 6 to 7 in 0,oi mm. coarsely punctate; puncta 7 in 0,01 mm. Ventral side with 

 a row of short striae along the median line and towards the ends of the valve. Ventral striai 

 frequently crossed by a longitudinal line. — A. S. Atl. XXVII f. 4(5. A. (/ii/nntea rar. andesitica 

 Pant. II "p. 36; III PI. XVII f. 243. 



Marine: Grulf of Naples! Java! Japan! S:n Pedro Calif., fossil (Kinker), Campeachy Bay! 

 Pensacola! Colon (Deby Coll.)! Hungary, Bory fossil (Pant.)? 



Var. ohsrura C'l. — V. in L. 0, 10 to 0,2o, in B. O.01.5 to 0,o4 mm. Strise on the dorsal 

 side () to 7 in 0,01 mm.; puncta coarse, about 5 in 0,oi mm. forming longitudinal undulating lines. 

 Ventral side with a row of short, radiate stria? along the whole median line. — A. S. Atl. PI. 

 XXVIII f. 20 (without name). Icon. n. PI. IV f. 28, 29. 



Marine: Balearic Islands! Gulf of Naples (Deby Coll.)! Sumbava (Kinker Coll.)! Sumatra 

 (Deby Coll.)! Macassar Straits! ('ampeachy Bay (Atl.). 



Forma minor. Stria- 8 in 0,oi mm. L. 0,i 1 mm. — A. S. Atl. XL f. 'IH, 29. 



Marine: S:t Peter, Hungary (fossil)! Leton Bank (Atl.). 



Var. fusca A. S. (1875). — V. in It. O.o? to 0,i2 mm. Dorsal strite 10 in 0, 01 mm. coarsely 

 punctate; puncta 8 in 0,oi mm. Longitudinal line somewhat obscure. Ventral part broad, struc- 

 tureless, except at the ends, where are short sets of oblique, graniilate stria?. Zone with irregu- 

 lar small puncta, giving it a brownish colour. — A. fiisca A. S. Atl. XXVII f 68. 



Marine: Gulf of Naples! Red Sea (Van Heurck Coll.)! Java! Labuan! Macassar Straits! 

 Gulf of Mexico (Atl.), Bahia! Galapagos Islands! 



16. A. nodosa Brun. (1891). — V. with strongly arcuate dorsal margin, straight ventral 

 margin and broad, rounded ends. L. (),i'2 to 0,15; B. 0,o42 mm. Median line slightly biarcuate. 

 Dorsal side without axial and central areas, divided into two parts by a longitudinal line (or 

 crest), of which the interior bears short rows of large puncta, and the exterior strong costte (4 in 

 l>.oi mm.) alternating with rows of large ocelli (4 to 5 in 0,oi mm.), which form longitudinal, 

 slightly undulating lines. Ventral side of the valve narrow, with shoi't and strong costae. — 

 D. especes nouv. p. 9 PI. XII f. 2. 



Marine: Nossibe (Brun Coll.)! Japan (Brun), Samoa! Macassar Straits! 



One of the largest ami stoiitest forms of Amphora. The strong central nodule, the crest 

 enclosing, on the dorsal side of the valve, a furrow, i-ecal Diploneis, as does also the structure ot 

 transverse costai, alternating with ocelli. 



17. A. Oculus A. S. (1.S75). — V. lunate, with obtuse ends. L. 0,07 to 0,1.=.; 0,02 to 0,04 

 mm. Median line approximate to the ventral margin, straight or slightly biarcuate. Axial area 

 indistinct; central area large, rounded. Longitudinal line at a considerable distance from the 

 median line. Striffi on the dorsal side 7 to 10 in 0,oi mm., coarsely punctate; puncta about 8 in 

 0,(H mm. Ventral side narrow, with coarse stria; in its whole length. — Atl. XXVII f. o2. A. 

 Oc. var. fossiUs Pant. I p. 22 PI. XIV f. 127. A. Wachenhusemi Janisch A. S. Atl. XL f. 38 (1876). 



Marine: Gulf of Naples (Deby, Brun Coll.)! Seychelles (Van Heurck Coll.)! Sumbava (Kinker 

 Coll.)! China (Deby Coll.)! Japan (Atl.), Campeachy Bay (Atl.). 



Var. Farcimen A. S. (1875). — L. 0,00 to 0,07; B. 0,oi9 mm. Central area less di.stinct. 

 StrijE 11 in 0,oi mm.; puncta 10 in 0,01 mm. — A. Fare. A. S. Atl. XXVII f. 56, 57. 



Marine: Seychelles (Van Heurck ('oil.)! Samoa (Atl.), Galapagos Islands! Campeachy Bay (Atl.). 



18. A. Schniidtii Grpn. (1875). — Frustule in outline elliptical with truncate ends- 

 L. 0,09; B. 0,04 mm. Median line elevated to a biarcuate keel. Dorsal side with coarsely punctate 

 strife, 9 in 0,oi mm. reaching to the median line. Ventral side also with coarsel}' punctate stritt. 

 Zone with two or more longitudinal rows of large puncta. — A. S. Atl. XXVIII f. 2. 



JVIarine: China! Samoa (Atl.), Bahia, Ilio Janeiro, Porto Seguro (Deby Coll.)! 



