138 p. T. CLEvr-:, synopsis of the naviculoid diatoms. 



(5 to 8 in 0,0 1 inm.), coarsely, transversely striate; strife 8 to i» in 0,ui mm. On both sides of 

 the longitudinal margins is a broad hyaline limbus. V. narrow, linear, with broad capitate ends. 

 Median line sliglitly biarcnate. Dorsal side witli 8 strife in 0,oi mm., coarsely but obscurely 

 punctate. Ventral side without strife, and with a longitudinal line close to the median line. — 

 Diatomiste I p. 159 PI. XXIIl f. 1, 2. 



Marine: Norway, Grrip! Morocco! Balearic Islands! Macassar Straits! (ralapagos Islands! 



The frustule has a considerable resemblance to A. exsecfn (tHTtn., but the valves are ditt'e- 

 rent. A. Umpida Jan. (A. S. Atl. XXXIX f. 8) is probably allied with this species, or is perhaps 

 a small variety of it, Imt the figure it not sufficient for identification. 



(i. A. sendaiana Brun (1891). — V. linear with obliquely rounded ends. L. (», 19; B. 0,02 

 mm. Median line biarcnate. Central nodule strong, dilated on the dorsal side to a stauros. Dorsal 

 side with 11, finely punctate strife in 0,01 mm. Ventral side without strife, and with a longitu- 

 dinal line. — D. especes nov. p. 9 PI. XII f. 1. 



Marine: Japan, fossil! 



According to Prof. Brun there is a line across the strife, which I liave not noted in an 

 original specimen, sent by him. If this line be not the margin of the frustule, and really crosses 

 the strife, this species may be removed from this group and placed in Diplamphora. 



7. A. Orovei Cl. (1892). — Frustule, of rectangular outline, gibbous on the back. L. 0,io.'-); 

 B. OjO.'i mm. Zone with several divisions, transversely striate; strife, 18 in 0,oi mm. V. linear, 

 with gibbous dorsal mai-gin and broad ends. L. 0,io to 0,12; B. 0,()i.'j mm. Strife on the dorsal 

 side 10 to 11 in 0,oi mm., finely punctate. Ventral side not striate and with a longitudinal line. 

 — Diatomiste I p. 158 PI. XXII f. 16, 17. 



Marine: Seychelles! Java! Sumbava (Kinker Coll.)! China! Macassar Straits! 



8. A. formosa Cl. (1875). — Frustule rectangular with rounded angles. L. <i,i4; B. 0,ot 

 mm. Zone with few, broad divisions, about 12 in 0,oi mm., finely transversely striate; strife 8 to 

 9 in 0,01 mm. V. linear with obliquely rounded, spathulate, or clavate ends, according to the 

 position of tlie valve. L. 0,o<t to 0,2; B. 0,02;") to O.oss mm. Median line biarcnate. Dorsal side 

 with 8 to 9 costate strife in (),oi mm., alternating with more or less distinct puncta, 15 to 18 

 in 0,01 mm. Ventral side structureless, with a longitudinal line. — A. S. Atl. XXVIII f. 34, 

 XXXIX f. 2. A. Sfudcrt Janisch A. S. Atl. XXXIX f. 1 (1876). 



Marine: Mediterranean Sea (Balearic Islands, Gulf of Naples)! Madagascar (Kinker Coll.)! 

 Ceylon (Colombo, Le Tcnirneur Coll.)! Sumatra (Deby Coll.)! Singapore! Sumbava (Kinker Coll.)! 

 Macassar Straits! Galapagos Islands! Colon (Deby Coll.)! Fossil: S:ta Monica, ('alif. 



Var. miniifa Cl. — L. of the frustule 0,08.5; B. 0,04') mm. Costfe 9 in U,oi mm. 



Marine: Macassar Straits! Bahia (Deby Coll.)! 



The valves of this very large and beautiful difitom have a very different shape according 

 to the position. A. Fcfifi Leud. Fortm. (De de la Malaisie p. 10 PI. I f. ;>) may be a small form 

 of this .species, which I am unable to decide without original specimens. 



9. A. Scala ('l. and Grove (1S92). — Frustule of rectangular outline, with slightly concave 

 sides and rounded ends. L. 0,14; B. 0,o5 mm. Zone with broad divisions (about 2 in 0,oi mm.) 

 which are transversely costate (costfe about 5, .5 in 0,oi mm.). V. in B. 0,oi.5 mm. Dorsal side 

 with smooth, costate strife, 5 to 6 in 0,oi mm.; intermediate space not distinctly punctate. Ven- 

 tral side smooth with a strong longitudinal line. — Diatomiste I p. 158 PI. XXII f. 18, U). 



Marine: Macassar Straits! Porto Seguro (Deby Coll.)! 



Var. alafa Cl. — Dorsal side of the valve with a hyaline limbus. L. of the V. 0,24; 

 B. 0,0 18 mm. Strife 6 in 0,oi mm. 

 Marine: Macassar Straits! 



