Cymbella turgida, Greg. Mic. Journ. vol. 4. pl. i. fig. 18.
„ obtusa, Greg. I. c. fig. 19.
„ Pisciculus, Greg. I. c. fig. 20.
„ sinuata, Greg. I. c. fig. 17-
„ hyalina, Ag., Grev. B. F. p. 414. Not Diatomaceous.
„ m in o r , Ag. in Grev. B. F. = Cocconema Cistula.
„ eymbiformis Ag.-|g^,^^ g p
„ renitormis, Ag. J
Amphora Arcus, Greg. A. incisa, Greg. A. angularis, Greg.
Mic. Journ. vol. 3. pl. iv. figs. 4, 5 & 6 = Amphora ovalis, W . Sm. ?
Cocconeis transversalis, Greg. C. speciosa, Greg. C. distans,
Greg. C. costata, Greg. Mic. Journ. vol. 3. pl. iv. figs. 7, 8,9& 10
= Cocconeis Scutellum, W. Sm. ?
Eupodiscus Ralfsii ? ¡3, Greg. Mic. Journ. vol. 3. pl. iv. fig. 11.
Triceratium membranaceum, Brightwell. “ Walls of the frustule
extremely delicate ; sides convex ; angles attenuated, ending in
minute papillce ; frustule dotted over with very minute cells.
Diam. 1-233^.” Marine. “ Thames mud,” Bright. Mic. Journ.
vol. 1. p. 251. pl. iv. 15.
Triceratium obtusum, Ehr. “ Thames mud,” Bright. I. c. fig. 20.
„ comptum, Ehr., Bright. I. c. p. 249 & fig. 4. Roper,
Mic. Journ. vol. 2. p. 283 = ir. Favus, Synop. pl. v. 44?
Surirella Jennerii, Hass. Alg. p. 439. pl. cii. 15 = <S. bifrons, Synop.
pl. viii. 57?
Surirella fastuosa ft, Greg. Mic. Journ. vol. 3. pl. iv. \2 = S .fa s -
tuosa, Synop. pl. ix. 66 ?
Surirella tenera, Greg. Mic. Journ. vol. 4. pl. i. 38 = S. linearis,
Synop. viii. 58 ?
Amphiprora vitrea ft, Greg. Mic, Journ. vol. 3. pl. iv. \4 = A. elegans,
W. Sm. ?
Navicula Palea, Hass. Aig. p. 430. pl. cii. 10.
„ Platystoma, Ehr., Hass. Alg. p. 431. pl. cii. 6.
„ birostrata, Greg. Mic. Journ. vol. 3. pl. iv. 15.
„ rhombica, Greg. I. c. fig. 16.
„ gastroides, Greg. 7.c. fig.l7 = iV.j!UiSi(fa, Synop. xvii. 145.
„ crassa, Greg. I. c. fig. 18.
„ maxima, Greg. I. c. fig. 19.
„ Trochus, Ehr., Greg. Mic. Journ. vol. 4. pl.i. 2.
Navicula dnbia, Kiitz., Greg. I. c. fig. 3.
Bacillum, Ehr., Greg. I. c. fig. 4.
„ lacustris, Greg. Mie. Journ. vol. 4. pl. i. fig. 23.
„ lepida, Greg. I. c. fig. 25.
„ incurva, Greg. I. c. fig. 26.
„ longiceps, Greg. I. c. fig. 27.
Pinnularia varians, Greg. P. mutabilis, Greg. Mic. Trans, vol. iii.
p. 10. pl. ii. figs. 1-33.
In the paper quoted. Dr. Gregory figures and describes a number of forms
under tbe above names, which vary greatly in the outline and size of their
valves, but are all referred by him to two typical modes of striation, viz. Fin-
nularia varians, with 14 to 18 striae in ’OOl'', and P. mutabilis, with 24 to 26
striæ in ’OOl". In his remarks on these species. Dr. Gregory seems disposed
to consider that form and size are not to be regarded as of specific importance,
justly observing, “ that the more the Diatomaceæ are studied, the more do
we perceive that in many species the shape or outline is subject to endless
variations.”
Ill tbe absence of any specific descriptions of P. varians and P. mutabilis,
I must therefore conclude that the characters Dr. Gregory attributes to these
species are to be sought for in the striation only ; and as these correspond
to those given in the Synopsis to Navicula Semen, N. túmida, Pinnularia oblonga,
P. peregrina, P. acuta, P. radiosa, &c., I feel obliged to conclude, that
all the forms included under P. varians and P. mutabilis may he referred to
one or other of the species I have just mentioned.
Pinnularia exigua, Greg. Mic. Journ. vol. 2, pl. iv. 14 = P . mutabilis,
Greg. Mic. Trans, vol. 3. pl. ii. 18 b.
Pinnularia parva, Greg. I.e. fig. 11.
„ apiculata, Greg. Mic. Journ. vol. 3. pl. iv. 21.
„ Gastrum, Ehr., Greg. Mic. Journ. vol. 3. pl. iv. 20.
„ megaloptera, Ehr., Greg. Mic. Journ. vol. 4. pl. i. 6 =
P . lata, Synop. xviii. 167?
Pinnularia Dactylus, Ehr., Greg. Mic. Journ. vol. 4. pl. i. 7 = P.
viridis, Synop. xviii. 163 ?
Pinnularia pygmæa, Ehr., Greg. Mic. Journ. I, c. fig. 8.
linearis, Greg. I. c. fig. 29.
digito-radiata, Greg. I. c. fig. 32.
subcapitata, Greg. I. c. fig. .30.
E lgen sis, Greg. I. c. fig. 33.
globiceps, Greg. I. c. fig. 34.