VEG A-EXPEDITIONENS VETENSKAPLIGA ARBETEN. 495 
0,01 mm. Specimens from the Balearic Islets and from the 
Cape of Good Hope have 16 strie in 0,01 mm. 
M. (acutiuseula Grun. Mpt. var.?) Labuensis Ol. — Valve elon- 
gate, with almost parallel margins and subeuneate ends. Me- 
dian line straight with approximate accompanying lines. Strige 
16—17 in 0,01 mm. parallel or a little radiant near the ends, 
composed of puncta, forming longitudinal strie. Loculi of 
equal size, 7—8 in 0,01 mm. — Length 0,064 mm. Breadth 
0,016 mm. — P1. 35, fig. 5. 
Mr. Grunow has kindly sent me a sketch of his not yet 
published M. acutiuscula from the Seychells, which differs by 
regular elliptic outline and has 16—21 strie in 0,01 mm. 
M. (baltica Grun. var.?) Citrus Ol. — Broadly oval, with 
apiculate ends. Strix 18—19 in 0,01 mm., more close near the 
ends, about 23 in 0,01 mm., composed of puncta, which form 
longitudinal lines, at a right angle to the strie. Loculi 
marginal of equal size 8—10 in 0,01 mm. Median line straight, 
with very approximate accompanying lines or furrows. Length 
0,035 —0,04 mm., breadth 0,02—0,024 mm. — Pl. 35, fig. 7. 
This well defined form has very little resemblance to M. 
baltica Grun. in Van Heurck Syn. Pl. IV, fig. 24, but Mr. Gru- 
now thinks nevertheless that it may be a variety of the 
latter species. According to Grunow, it comes very near to 
Phlyctenia minuta Kätz. I have seen the same form in samples 
from Honolulu. 
M. Kjellmanii Cl. N. Sp. — Elongate, with apiculate ends, 
loculi marginal of almost equal size, 4in 0,01 mm. BStrie fine, 
22 in 0,01 mm., parallel, or a little radiant in the middle, 
punctate, puncta forming oblique lines. Median line straight. 
Jentral nodule elongated. Length 0,06 mm. Breadth 0,014 mm. 
— PI. 35, fig. 6. 
Rhoikoneis genuftexa Grun. (Verh. 1863 pap. 147) Strie on 
the convexe valve 23 on the concave 20 in 0,01 mm. 
Navicula rectangulata Greg. (Donk. Brit. Diat. P1. X, fig. 3. 
Cl. & M. Diat. No 301). 
N. Pandura Ehb. (A. Schm. Atl. Pl. XI, fig. 1). 
N. diplostieta Grun. (A. Sehm. Atl. P1. XIII, fig. 29). 
N. multicostata Grun. (A. Schm. Atl. Pl. XI, fig. 18). 
NIA pISD OR N(ASS Sem At; P1 ACIKP SS. 28vandeR 
LXIX, fig. 43). 
N. futilis A. Schm. var.:? (Atl. Pl. XIII, fig: 18). 
N. lacrimans A. Schm. (Atl. P1. XII, fig. 61). 
N. Lyra Ehb. 
