496 



CLEVB, DIATOMS. 



N. ahrupfa Greg. var. 



N. hidlafa 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. Grceffii Grun. (A. Schm. Atl. PI. Vll, fig. 5—6). 

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

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

 JV. suborhmdaris Greg. (A. Schm. Atl. PL VIII, fig. 1, 2, 5). 

 N. Campylodiscus Grun. (A. Schm. Atl. PL VIII, fig. 9). 

 N. notahilis 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. Jmmerosa Breb. (A. Schm. AtL PL VI, fig. 4). 



N. carihcea CI. (A. Schm. AtL PL VI, fig. 10—12). 



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



N. sid)lyrata 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. sublyrato, 

 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. scoimlorum Breb. (Donk. B. D. PL 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. Stripe transverse and longitudinal 

 covering the whole valve. Transverse strioe 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 0,066 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. lahiensis CI. Length 0,o72 mm. Breadth 0,oi5 mm. 

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

 Outline elliptic with rounded ends. — Labuan, rare. 



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



