NAVICULA ELLIPTICA. 7 
rounded extremities, sometimes slightly constricted in 
the middle with broad subcuneate extremities; strize 
connivent, coarse, granular, about 18 in -001”, inter- 
rupted near to the median line by a gently incurved 
longitudinal line. 
Hab. Marine. Abundant in the sandy ripples on the 
sea-shore; Cresswell, Boulmar, and Tynemouth, North- 
umberland; South Shields (4. S. D.). Glenshira sand 
(Prof. Gregory). 
Navicula fusca, Gregory. 
Navicula Smithit, vax. fusca, Greg. Diat. of the Clyde, p.14, pl. i. fig. 15. 
Navicula fusca, Ralfs, in Prit. Inf. p. 898; Rabenh. Europ. Diat. p. 179. 
Navicula hyperborea, Grun. in Wien. Verh. 1860, p. 29, t. i. fig. 16, 
Pinnularia quadrifasciata, Ehren. Mikrogeo, t. xix. fig. 26. 
Plate I. fig. 5. 
Frustule large. V. oblong-elliptical, or elongated oval ; 
striz connivent, very coarse and granular, about 12 in 
001", bisected by a longitudinal incurved line; inner 
section narrow and fainter. 
This species is readily distinguished from N. Smithii, to 
which it is closely allied, by its much more elegant figure, 
coarser striz, larger size, and distinct: brown colour of the 
valve in balsam, 
Hab, Marine. Lamlash Bay Isle of Arran, Loch Fyne 
(Prof. Gregory); stomach of Ascidians near Hull (Mr. 
Norman). 
Navicula elliptica, Kiitzing. 
Navicula elliptica, Kiitz. Bac. p. 98, t. xxx. fig. 55; Rabenh. Europ. 
Diat. p. 179; Sm. Synop. vol. ii. p. 92; Ralfs, in Prit. Inf. 
p. 899. 
Navicula ovalis, Smith, Synop. vol. i. p. 48, pl. xvii. fig. 153. 
