8 p. T. OLEVE, ON SOME NEW DIATOMS. 



N. Hennedyi var, Tahitensis Cl. 



Broadly oval with almost parallel sides. Stride scarcely punctate, marginal 13 in 

 0,01 mm., central 15 in 0,01 mm. 



Length 0,05 mm. Breadth 0,023 mm. 



PL I, fig. 14, -%. 

 Tahiti (Eugenie Exp.). 

 This variety is remarkable for its almost smooth striae. 



6. Navicula rudis Cl. N. Sp. 



Broadly oval, with broadly rounded ends. Strias coarse, 6 in 0,01 mm. marginal 

 composed of about 5 8 large, separate puncta; central stria) composed of 2 3 puncta. 

 Length 0,052 mm. Breadth 0,032 mm. 

 PL II, fig. 17, '""Vx. 

 Balearic Islets rare (leg. Dr. Soderlund). 



This peculiar form belongs evidently to the Nav. Lyra section. It approaches in 

 some respects N. spedabilis Greg, and N. prcetexta Ehb., but it differs of both. 



The numerous forms, belonging to this section, are so closely allied, that it is 

 impossible to decide what are species or what varieties. Another most beautiful and 

 gigantic form of this section is the following: 



7. Navicida {excavata Grev. var.?) Angelorum Cl. 



Very large, broadly oval, with rounded ends. Area large bilobate. Striaj pun- 

 ctate, radiant, 6V2 '" 0>01 ntmi- (8 near the ends). Central striae 11 72 i" O^Ol "fUT'- 

 Length 0,22 mm. Breadth 0,12 mm. 



PL II, fig. 20, "7i. 

 Fossil: California, Sancta Monica los Angelos (comm. by Dr. G. Eisen). 



8. Navicula Holmiensis Cl. 



Valve large, oblong elliptic, with rounded ends. Striae slightly radiant, 12^/^ in 

 0,01 mm., indistinctly punctate, covering a little more than half the valve and leaving 

 round the median line an irregular area. 



Length 0,0701 mm. Breadth in 0,023 mm. 

 PL II, fig. 18, "%. 



Slightly brackish water near Waxholm (entrence to Stockholm) leg. Lagerstedt 

 and 0. Nordstedt. 



This form agrees in general appearance with N. latiuscida KtlTZ. {N. patula W. 

 Sm.), but has more distant striae, which in N. latiusculn are 18 in 0,01 mm. and pa- 

 rallel. 



