496 



CLE re, DIATOMS. 



N. abrupta Greg. var. 



N. huUata Norm. (T. M. S. I, pag. 8, PL II, fig. 6). 



N. clavata Greg. (T. M. S. IV, pag. 46, PI. V, fig. 17). 



N. exul A. Schm. (Atl. PI. II, fig. 13). 



N. Grcefii Grun. (A. Schm. Atl. PI. VII, fig. 5—6). 



N. Smithii Breb. (A. Schm. Atl. PI. VII, fig.. 14— 18). 



N. nitescens Greg. (A. Schm. Atl. PI. VII, fig. 38). 



N. suborUcularis Greg. (A. Schm. Atl. PI. VIII, fig. 1, 2, 5). 



N. Campijlodiscus Grun. (A. Schm. Atl. PI. VIII, fig. 9). 



N. notaUlis Grev. (A. Schm. Atl. PL VIII, fig. 46). 



N. latissima Greg. (T. M. S. IV, pag. 40, PL V, fig. 4. A. 

 Schm. Atl. PL VI, fig. 7). 



var. hamorthensis Grun. (A. Schm. Atl. PL VI, fig. 8). 



N. humerosa Br^b. (A. Schm. Atl. PL VI, fig. 4). 



N. caribcea CI. (A. Schm. Atl. PL VI, fig. 10—12). 



N. hrasiliensis Grun. (A. Schm. Atl. PL VI, fig. 21 and 32). 



N. suUyrata Grun. — Valve constricted in the middle, 

 covered with parallel or sub-parallel striae, composed of distinct 

 puncta, 12 in 0,oi mm., reaching to the median line. Length 

 0,046 mm. Br. 0,oi mm. at the constriction 0,oo7 mm. — PL 35, 

 fig. 17. 



Mr. Grunow has sent me a sketch of his N. sublyrata, 

 which lives in brackish water in North America. The Ameri- 

 can species is not so strongly constricted in the middle as 

 my specimen from Labuan. N. Ceylanensis Leud. Fortm. 

 (Diat. Ceyl. PL II, fig. 25) seemes to be nearly related to this 

 species. 



N. scopulormn Breb. (Donk. B. D. PI. XII, fig. 5). 



N. O'Mearii Grun. Mpt. — Elongate, with more or less 

 rounded ends; median line straight, terminal nodules in the 

 ends, central nodule small. Striae transverse and longitudinal 

 covering the whole valve. Transverse striae almost parallel, 

 or very little radiant, 16 to 17 in 0,oi mm., longitudinal 18 — 

 21 in 0,01 mm. 



forma typica Grun. Mpt. — Length 0,o66 mm. Breadth 0,oo9 

 mm. Transv. str. 17, longit. 20 in 0,oi mm. Outline lanceolate, 

 equally tapering from the middle to the somewhat acute ends. 

 — Seychells, Grun. 



var. lahuensis CI. Length 0,o72 mm. Breadth 0,oi5 mm. 

 Transv. striae 17 in 0,oi mm. longitudin. striae 21 in 0,oi mm. 

 Outline elliptic with rounded ends. — Labuan, rare. 



var. minor CI. Length 0,o5 mm. Breadth 0,on mm. Trans- 



