NAVICULA INFLATA, 21 
Navicula Semen, Ehrenberg. 
Navicula Semen, Ehren. Amer. 1843, t. IV. ii. fig. 8; Kiitz. Bac. p. 99, 
t, xxviii. fig. 49; Rabenh. Siissw. Diat. p. 38, t.v. fig. 2, and 
Europ. Diat. p. 194; Sm. Synop. vol. i. p. 50, pl. xvi, fig. 141; 
Ralfs, in Prit. Infus. p. 900. 
Pinnularia Semen, Ehren. Mikrogeo. t. XTV. fig. 12, t. XVI. iii. fig. 26, 
t. XVII. ii. fig. 8P 
Amphiprora navicularis, Ehren. Mikrogeo. t. IIL. i. fig. 10, 11, & iii. 
fig. 8, t. IV. ii. fig. 16, t. V. i. fig. 10. 
Plate IIT. fig. 8. 
V. oblong-elliptical or oval, slightly constricted into 
broad flattened extremities; striz reaching to the 
median line, coarse, obscurely granular, convergent, 
stouter and more distant, but of equal length around 
the central nodule. Variable in size and outline. 
It is difficult to say what species is meant by Ehrenberg 
as Pinnularia Semen, as different species are figured under 
this name in the ‘ Mikrogeologie,’ one of these only being 
striated (t. xiv. fig. 12), and apparently identical with Pin. 
Gastrum (t. xv. A. fig. 23); the other figures are unstri- 
ated, and none of them are identical with N. Semen of 
Smith’s Synopsis, which I have adopted as the genuine 
form, and which is identical with Amphiprora navicularis, 
Ehren. Mr. Ralfs describes the strie of N. Semen as 
“ obsolete or apparent,” Prof. Smith as ‘‘ distinct.” 
Hab. Fresh water, frequent. Peterhead deposit (Prof. 
Smith); near Hull (Mr. Norman); River Coquet North- 
umberland (A. S. D.). 
Navicula inflata, Kiitzing. 
Navicula mflata, var. 8, Kiitz. Bac. p. 99, t. iii. fig. 36, 3; Sm. Synop. 
vol. i. p. 50, pl. xvii. fig. 158; Rabenh. Europ. Diat. p. 191. 
Pinnularia inflata, Rabenh. Siissw. Diat. p. 44, t. v. fig. 10¢. 
Plate III. fig. 9. 
Frustule small. V. elliptical, extremities produced, broad 
