10 Pp. T. CLEVE, ON SOME NEW DIATOMS. 
N. Cluthensis var. minuta Ct. 
Broadly oval, with rounded ends. Strie slightly radiant, composed of distinct 
puncta, abbreviate around the central nodule, 15 in 0,01 mm. in the middle, 18 in 
0,01 mm. in the ends. 
Length 0,03 mm. Breadth 0,014 mm. 
Play te ee 
Florida, Pensacola in a gathering, sent by Mr. Cur. Fepieerr. 
The following varieties of N. Cluthensis are described: 
a. genuina (Grec. Diat. of Clyde p. 6, Pl. I, fig. 2) with 8 strie in 0,01 mm 
and no area. Length 0,035—0,04 mm. 
6. erythrea (N. erythrea Grun. Verh. 1860 p. 539, Pl. HI, fig. 17) with 10—12 
striz in 0,01 mm. and no area. Length 0,05—0,06 mm. 
ce. Finmarchica Grun. (in Cx. et Grun. Arct. Diat. p. 40, Pl. II, fig. 49) with 
11—-12 striz in 0,01 mm. and very small area. Length 0,022—0,024 mm. 
d. maculifera Cu. with 11 strie in 0,01 mm. and tolerably large area. 
e. minuta CL. with 15—18 striae in 0,01 mm. and tolerably large area. 
13. Navicula bicuspidata Ci. et Grun. 
Oblong, slightly constricted in the middle, apiculate. Strie coarse, finely pun- 
ctate, 6 in 0,01 mm., shortened around the middle. 
Length 0,04 mm. Breadth 0,015 mm. 
Bi, tie. Bag ee 
Mediterranean, Pithuisian Islands in a gathering sent by Prof. V. B. Wirrrock. 
The nearest allied to this species seems to be Nav. directa Sm. The Nav. salva 
A. Scum. and Nav. opima Grun. have the terminal nodules at some distance from the 
apices. 
14. Navicula mesoleia Cu. N. Sp. 
Very convex, linear with cuneate ends. Strie coarse, 15 in 0,01 mm., very 
slightly radiant, almost reaching the median line, absent from the middle of the valve, 
where there is a transverse blank space. 
Length 0,04—0,06 mm. Breadth 0,005—0,008 mm. 
Pl. I, fe. 26-4. and & °°"), 
Fresh water, Brazil, lez Dr. Warminc. (Cu. et Métx. Diat. N:o 193.) 
This form has the appearance of some smaller varieties of N. Pinnularia Cu. 
(Cu. et Grun. Arct. Diat. p. 27) but is more convex and has closer striz. 
15. Navicula Fromentere Cu. N. Sp. ; 
Small, elliptic. Striz coarse, costate,.6 in 0,01 mm., reaching the median line, 
but abbreviated around the nodule. 
Length 0,0375 mm. Breadth 0,0128 mm. 
Ply I, tie, 24, Pr 
Balearic Islets (F. SODERLUND). 
