Marine or brackish water. “ Brooks,” Lewes, Sept. 1850. Var./3. investing
a sponge, Poole Bay, Nov. 1849, JF. Sm.
Plate XX. 206. Outline of smaller var. 206 (3.
Sect. II. Striæ transverse and longitudinal.
14. Pleurosigma Balticum, TF. Sm. V. linear, attenuated towards
the obtuse extremities, fle.xure terminal ; colour dark brown ; long,
and trans, striæ 38 in -OOl". Length -0083" to -0142". v.v.
¡3. Smaller, more gradually attenuated.
y. Attenuated throughout ; striæ obscure.
W. Sm. Ann. 2nd Ser. vol. ix. p . 8. p i . ii. 1, 2 & 3. Prit. Anim. iii. 144.
XX. 1, 2, 3. Navicula Baltica, Ehr. Inf. p i . xiii. 10. Kütz. Bacill. iv. 32.
Marine or brackish water ; frequent. Poole Bay, Aug. 1848. Belfast Bay,
Aug. 1849. Coast of Sussex, Aug., Sept., Oct. and Nov. 1850, TF. Sm.
Cockerham Marsh, Lancashire, Oct. 1849, Mr. Johnson. ¡3. & y. Coast of
Sussex, Oct. 1851, TF. Sm.
Plate XXII. 207. Outline of young (?) specimens, 207 ¡3. & 207 y. Outline
of F. V. PI. XXIII. 207. Frustule with endochrome. Frontispiece,
fig. CCVII.
15. Pleurosigma Strigilis, TV. Sm. V. lanceolate, acute, flexure
considerable; colour pale brown; long, striæ 40 in "OOl"; trans,
striæ 36 in '001". Length -0116" to '0142". v.v.
W. Sm. Ann. 2nd Ser. vol. ix. p. 8. pi. ii. 4. Prit. Anim. xx. 4.
Brackish water. Hull, Mr. li. Harrison. Iford, Sussex, Oct. 1852, TF.Sm.
Plate XXII. 208.
16. Pleurosigma acuminatum, TV. Sm. V. lanceolate, acute, flexure
considerable; colour pale brown; long, striæ 40 in -OOl";
trans, striæ 52 in -OOl". Length -0050" to -0065". v.v.
W. Sm. Ann. 2nd Ser. vol. ix. p. 9. pi. ii. 5. Prit. Anim. xx. 5. Navicula
Sigma, Ehr. Inf. xiii. 12. Prit. Anim. iii. 140. Kütz. Bacill. iv. 26.
Marine. Shoreham Harbour, June 1850, TF. Sm. Menai Straits, Prof.
TFilliamson. Higham, Mr. Shadholt. Folkestone, Mr. Capron, Nov. 1852.
17. Pleurosigma distortum, TV. Sm. V. lanceolate, abruptly bent
towards the obtuse extremities ; colour pale pink ; “ trans, striæ 75
in -OOl"; long, striæ 65 in -OOl".” (11. B.) Length -0026" to -0042".
v.v.
W. Sm. Ann. 2nd Ser. vol. ix. p. 7. pl.i. 10. Prit. Anim. xix. 10.
Marine. Coast of Sussex, Aug. 1850, TF. Sm. Folkestone, Mr. Capron.
Plate XX. 210.
18. Pleurosigma Fasciola, TV. Sm. V. lanceolate, extremities produced,
flexure considerable; colour pale pink; trans, striæ 64 in
•001". Length -0036" to -0048". v.v.
¡3. Extremities abruptly bent.
Ceratoneis Fasciola, Kütz. Bacill. iv. 4.
Marine. Belfast Bay, Aug. 1849. Poole Bay, Sept. 1850. Hastings,
Nov. 1851, W. Sm. Hull, Mr. R. Harrison.
Plate XXI. 211. A’ar./3. 211
19. Pleurosigma macrum, n. sp. V. lanceolate, extremities produced,
flexure terminal, moderate ; “ trans, striæ 85 in •OOl".” (R. B.)
Length -0083" to -0106". v.v.
Brackish water. Iford, Sussex, Oct. 1852, TF. Sm.
Supp. Plate XXXI. 276.
20. Pleurosigma prolongatum, TV. Sm. V. lanceolate, narrow,
acute, flexure moderate ; “ trans, striæ 65 in '001".” (R. B.) Length
•0043" to -0060". v.v.
W. Sm. Ann. 2nd Ser. vol.ix. p. 9. pi. ii. 7. Prit. Anim. xx. 7.
Marine. Poole Bay, Oct. 1849. Shoreham, Sept. 1852, TV. Sm.
Plate XXII. 212.
21. Pleurosigma tenuissimura, n .sp . V. very narrow, linear-lanceolate,
acute, flexure considerable; striæ 48 in •OOl". v.s.
Brackish water. Walton, Essex, 3Ir. Topping, April 1852.
Plate XXII. 213.
22. Pleurosigma littorale, TV. Sm. V. broadly lanceolate, acute,
flexure considerable; colour purplish; long, striæ 24 in -001";
trans, striæ 50 in -OOl". Length -0046" to -0063". v.v.
F 2