NAVICULA LIMOSA. 73 
Navicula scopulorum, De Brébisson. 
Navicula scopulorum, Bréb. in Kiitz, Spec. Alg. p.81; Ralfs, in Prit. Inf. 
p. 895; Rabenh. Siissw. Diat. p. 41, t. v. fig. 7. 
Navicula mesotyla, Ehren. Amer. 1843, p. 180; Kiitz. Bac. p. 99, t. v. 
fig. 3, and t. xxviii. fig. 84; Rabenh. Siissw. Diat. p. 41, t. v. 
fig. 6 P 
Pinnularia Johnsonit, Sm. Synop. vol. i. p. 58, pl. xix. fig. 179; Rabenh. 
Europ. Diat. p. 211. 
Plate XII. fig. 5 
Frustule much elongated, slender. V. narrow, linear, in- 
flated in the middle and at the rounded extremities ; 
striz reaching to the median line, parallel, transverse, 
faint, 56 in ‘001"; colour of dry valve brownish. 
Hab. Brackish water. Pilling near Lancaster (Mr. 
Johnson, Feb. 1851). Shoreham, Sussex, March, 1851 
(Prof. Smith). Piers, Victoria Dock, Hull, and Lagoon, 
Grimsby (Mr. Norman) ; Bootle shore near Liverpool (Mr. 
Comber). 
Navicula limosa, Kiitzing. 
Navicula limosa, Kitz. Bac. p. 101, t. iii. fig. 50; Rabenh, Siissw. Diat. 
p. 41, t. vi. fig. 31, and Europ. Diat. p. 188; Ralfs, in Prit. 
Inf. p. 894; var, inflata, Grunow, in Wien. Verh. 1860, p. 544, 
t. iil. fig. 8¢.; and var. bicuneata, Grunow, in Wien. Verh. 
1860, p. 544, t. iii. fig. 7. 
Navicula gibberula, Kitkz, Bae. p. 101, t. iii. fig. 50*; Sm. Synop. vol. i, 
p. 51, pl. xvii. fig. 160; Ralfs, i in Prit, Ink p. 895. 
Navicula leptogongyla, Ehren. ; Kiitz, Bae. p. 99, t. iv. fig. 9; Rabenh. 
Siissw. Diat. p. 41, i v. fig. 8 
Navicula tumidula, Rabenh. Siissw. Diat. p. 41, t. v. fig. 9, and Europ. 
Diat. p. 188; Ralfs, in Prit. Inf. p. 895, 
Navicula Silicula, Ehren. Amer. p. 181. n. 161, Mikrogeo. fig. numer. ; 
Kiitz. Bae. p.101; Ralfs, in Prit. Inf. p. 894 ; Rabenh. Siisew. 
Diat. p. 41, and Europ. Diat. p. 206. 
Plate XII. figs. 6a & 66. 
Frustule small, oblong. V. highly convex, narrow, linear, 
