72 
Frustule small; valve lanceolate, with conspicuous terminal 
nodules; striz oblique, connivent, and shorter near the central 
nodule. : 
Hab.—Marine, scarce. Prince’s Bay. (Fig. 10:) 
NAVICULA CUSPIDATA, Kiitz. 
Navicula cuspidata, Kutz., Bacill., p. 94., t. II., figs. 24 and 37; Sm. Syn., 
Vol. I., p. 407, pl., XVI., fig. 131; Ralfs in Prit., Infus., p. 905, pl. XII., fig. 53 
Rabenh., Sussw Diats., p. 37, t. V., fig. 16; and Europ. Diats., p. 170; Donkin., p. 
39-, pl. VI., fig. 6; Brun., p. 66, pl. VII., fig. 6; Van Heurck, Syn., pl. 12, fig. 4. 
Valve broadly lanceolate, with slightly produced apices ; striz 
parallel, transverse, very finely dotted and reaching to the med-. 
ian line. 
Hab.—Fresh water, common. In ponds, Clifton, New Brigh- 
ton. (Fig. 11.) 
NAVICULA GIBBA, Ehr. 
Navicula gibba, Van Heurck, Suppl. pl. A., fig. 12. 
Pinnularia gibba, Sm., Syn., Vol. 1., p. 58., pl. XIX., fig. 180;. Brun., p. 85, 
pl. VIII, fig. 17. 
Pinnularia tabellaria, Sm., Syn., vol. I. p. 58., pl. XIX., fig. 181. 
Stauroptera gibba, Ehr., Rab., Sussw., Diat., p. 49., t. IX., fig. 3. 
Stauroneis gibba, Kutz., Bacill., p. 107, t. XXIX., fig. 24; Ralfsin Prit. Infus., 
P- 914. 
Valve linear, inflated in the centre and at the extremities ; 
striz not reaching the median line, costate, oblique. 
Hab.—F resh water, common. In ponds and wayside ditches 
at Clifton, New Brighton, New Dorp. , (Fig. 12.) 
NAVICULA HUMEROSA, De Bréb. 
Navicula humerosa, Sm., Syn., Vol. II., p: 93; Ralfs in Prit. Infus., p. 903 ; 
Rabenh., Europ. Diats., p. 20; Donkin, p, 18., pl. Ill., fig. 3; Van Heurck, pl. I, 
fig. 20. 
N. quadrata. 
NV. crassa. 
Valve elliptical-linear ; extremities truncate ; striae oblique, 
granular, reaching nearly to the median line, shortened opposite 
the central nodule, thus forming a blank space. 
Hab.—Marine, frequent. South Beach, Clifton, and in the 
brackish water of the salt meadows at New Dorp. (Fig. 13.) 
Mr. Donkin remarks that ‘this species is very variable in size 
and outline. In elongated specimens it is frequently constricted 
in the middle ; it is closely allied to WV. Jatissima and N. granu- 
Jata, but readily distinguished from them by its very much finer 
