rsaA-EXPEDITIONENS V ETEN SKAPL IGA ABBETES. 



497 



A-erse strise 16, slightly radiant, longitudinal 18 in 0,oi mm. 

 — Port Jackson, rare. 



This species comes near to Navicula Vegse CI. (=Pleuro- 

 sigma Kjellmanii CI. Arct. Diat. PL IV, fig. 80). 



iV. cancellata var. impressa Ldt. (Bih. t. K. Sv. Vet. Ak. 

 Handl. 3 No 15, fig. 3). 



N. Zostereti Grun. (A. Schm. Atl. PI. XL VII, fig. 44). 



The specimens from Labuan resemble exactly the figure 

 quoted. The strise are very finely transversely lineate as in 

 all species of the directa-group. 



N. Bruchii Grun. (K. Sv. Vet. Ak. Handl. 18, No 5, pag. 

 13, PI. Ill, fig. 35). This species, classed among the quadrin- 

 seriatae-group, is beyond doubt very nearly related to N. directa, 

 and has transversely lineate strise. 



N. velata A. Schm. (Atl. PI. XLVIII, fig. 33—34). 



N. aspera Ehb. (A. Schm. Atl. PI. XLVIII, fig. 2—5). 



N. liber W. Sm. (A. Schm. Atl. PI. L, fig. 16—18). 



N. maxima Greg. (T. M. S. IV, pag. 39, PI. V, fig. 2). In 

 the Labuan material were found both the typical form (A. S. 

 Northsea Diat. PI. II, fig. 44) and a variety with finer striae 25 

 in 0,01 mm. Length O.oes. Breadth 0,oi6 mm. 



N. samoensis Grun. (A. Schm. Atl. PI. L, fig. 43—44). 

 Strise 10 — 13 in 0,oi mm. Length 0,054 mm. to 0,085 mm. Breadth 

 0,016 — 0,018 mm. 



N. Uanda A. Schm. (N. Sea Diat. PI. II, fig. 27). 



N.^ triundulata Grun. (T. M. S. 1877, pag. 178, PI. CXCV, 

 fig. 10). 



N. qtiadrisulcata Grun. (Novara Exp. Alg. pag. 101, PI. I, 

 fig. 14). 



PleurosigmaformosumW. Sm. (Van Heurck Syn. PI. XIX, fig. 4). 



P. decorum W. Sm. (Van Heurck Syn. PI. XIX, fig. 1). 



PI. angulatum W. Sm. — Oblique and transverse strise 20 — 21. 



Fl. strigosum W. Sm. (Van Heurck Syn. PL XIX, fig. 2). 



P. rigidum W. Sm. (Van Heurck Syn. PL XIX, fig. 3). 



P. australe Grun. (Novara pag. 21, PL I, fig. 18). 



P. marinum Donk. (T. M. S. VI, pag. 22, PL HI, fig. 3). 

 Transverse strise 20 oblique 19 in 0,oi mm. 



Donkinia carinata Donk. (Pleur. car. Donk. T. M. S. VI, 

 pag. 23, PL III, fig. 5). Length of the valve 0,o65 mm.; breadth 

 0,014 mm. Transverse strise 22, oblique 21—22 in 0,oi mm. 



D. recta Donk. (Pleur. r. D. 1. c. fig. 6). Length 0,093; 

 breadth 0,012 mm. Longitudinal strise 20, transverse striffi 21 

 in 0,01 mm. 



