KONGL. SV. VET. AKADEMIENS HANDLINGAR. RAND 26. N:0 2. 31 



Marine: Mediterranean Sea, Alexandria (Deby Coll.)! Levant (Grove Coll.)! Delaware (Lewis) 

 Florida! West Indies! Colon! Griilf of Mexico! Java (Atl.) Fossil Szåkal, S:t Peter, Hungary 

 (Pantocsek). 



Var. Janischii Castr. (1886). — Segments elliptic-laneeolate, obtuse. L. O, i; B. 0, 025 to 

 0,03, at the constriction O.ois mm. Marginal cellules 4 to 4, 5 in 0,oi mm. Cellules of the valve 

 10 to 11 in 0,01 mm. Transver.se .strife 2f) to 27 in 0, 01 mm. — Navic. Jan. Cästr. D. Voyage 

 Challenger p. 29 Pl. XXX f. 5. Mastogloia reticulata var. japonica Brun. D. fossiles du Japon 

 p. 72; 1889. Dictijoneis marginata A. S. Atl. CLX f. 17, 18, 19, 21. D. märg. v. Jan. A. S. Atl. 

 CLXXXVIII f. 50. 



Marine: Madagascar (Brun CoU.)! Cebu! Java (Atl.), Japan (Atl.), Samoa (Atl.). Galapagos 

 Islands! Bermiidas (Castr.) Florida! Campeachy Bay! Colon (Deby Coll.)! Oamaru fossil, (Atl.) 



Var. Clevei Brun. (1889). — Segments broad, elliptical, with ronnded ends. L. O, u to 0, 12.5; 

 B. 0,04 2, at the constriction 0,oi3 mm. Marginal cellules 3 to 4 in 0, 01 mm. — Mastogloia Clevei 

 Brun a. Temp. D. foss du Japon p. 39 Pl. IX f. 18. D. margin, v. Clevei A. S. Atl. CLXXXVIII, 46. 



Marine: Java! Japan fossil and living, (Brun). 



Var. intermedia Cl. — Segments narrovt^, elliptical. L. 0,12; B, O, os, at the constriction 

 0,014 mm. Marginal cellules 4 in 0,01 mm. Cellules of the valve 10 in 0,oi mm. Transverse 

 strise 24 in O.oi mm. — Mastogloia Clevei Brun. A. S. Atl. Pl. CLX f. 34, 35. 



Marine: Nossi Bé (Brun Coll.)! Japan (Atl.). 



Var. commutata Cl. — V. about 6 times longer than broad, gently constricted in the middle. 

 Segments narrow, elliptical to elliptic-laneeolate. Ends obtuse. L. 0, 11 to 0,12; B. 0,o2i to 0,025, 

 at the constriction 0, 01 to 0, 12 mm. Marginal cellules 5 to 6 in 0, 01 mm. Cellules of the valve 

 12 in 0,01 mm. Transverse strite 25 in 0, 01 mm. — Dictyoneis marginata f. elongata A. S. Atl. 

 CLX f. 30. 



Marine: Manila (Deby CoU.)! Macassar Straits (Grove Coll.)! Sumbava (Kinker CoU.)! Cam- 

 peachy Bay! Hio Janeiro (Deby CoU.)! 



Var. gigantea Cl. — V. as in the Var. commutata. • L. 0,i8; B. 0,044, at the constriction 

 0,022 mm. Marginal cellules 4 in 0, 01 mm. Cellules of the valve 9 in 0,oi mm. 



Marine: Oamaru, New Zealand, fossil (Grove CoU.)! 



Var. spectatissinia Grev. (1866). — V. strongly constricted, with cuneate, obtuse segments. 

 L. 0,09 to 0,13; B. 0,03, at the constriction 0,oi3 mm. Marginal cellules broad, 4 in 0, 01 mm. 

 Cellules of the valve coarse, 8 in 0, 01 mm. Transverse strite 23 in 0, 01 mm. — Navic. spectatissima 

 Grev. T. M. S. Vol. XIV p. 84 Pl. IX f. 29. Dictyoneis spect. A. S. Atl. CLX f. 24 to 26, 32. 



Marine: Zanzibar (Grev.) Seychelles (Van Heurcks CoU.)! Campeachy Bay (Atl.), Campeachy 

 Bank (Atl.). 



4. D. Thuniii Cl. (1890). — V. linear-lanceolate, with obtuse ends. L. 0,ii to 0,i5; B. 0,022 

 to 0,032 mm. Terminal fissures in contrary directions. Marginal cellules 4 to 5 in 0, 01 mm., of 

 equal size. CeUules of the valve about 11 in 0, 01 mm. Transverse strise 24 to 25 in 0, 01 mm. — 

 Cl. Diatomiste I p. 15. Icon. n. Pl. V f. 33. A. S. Atl. CLXXXVIII f. 44, 45. 



Marine: Red Sea (Atl.) Seychelles (Van Heurck CoU.)! Java! Cebu! China! BrazU. (Atl.). 



D. Thumii is nearly akin to D. marginata var. commutata. The fig. 31 Pl. CLX and fig_ 

 49 Pl. CLXXXVIII in A. S. Atl. seem to represent intermediate forms, as also Fsnidodictyoneis 

 hungarica Pant. III Pl. I f. 8. 



5. D. subeoiistricta Cl. N. Sp. — V. slightly constricted, with broad, elliptic-laneeolate 

 segments. L. 0,o.').t to 0,083; B. 0,024 to 0, 03, at the constriction 0,oi8 mm. Marginal cellules 4 

 in 0,01 mm. Cellules of the valve 9 in 0,oi mm. Transverse strite 23 in 0, 01 mm. — Pl. V f . 31. 



Marine: Madagascar! Cebu! Campeachy Bay! 



This form is nearly akin to D. marginata var. Janischii and is perhaps more correctly to 

 be appreciated as a less constricted form of this variety. 



