PLATE 1


Fig. Page
MELOSEIRA
3-4 Meloseira roeseana var. epidendron (Ehr.) Grun. 15
5-6 Meloseira roeseana Rab. 15
8-9 Meloseira distans (Ehr.) Kuetz. 14
10 Meloseira granulata (Ehr.) Ralfs 15
11-12 Meloseira sulcata Kuetz. 15
15-16-17 Meloseira undulata (Ehr.) Kuetz. 15
GAILLONELLA
13-14 Gaillonella nummuloides (Dillw.) Bory 16
LYSIGONIUM
7 Lysigonium moniliforme (Muell.) Link. 16
18-19 Lysigonium varians (Ag.) De Toni 17
HYALODISCUS
20 Hyalodiscus scoticus (Kuetz.) Grun. 18
21 Hyalodiscus radiatus var. arctica Grun. 17
22 Hyalodiscus stelliger Bail. 17
Note.—The figures in all of the plates, except when otherwise noted, are magnified 800 diameters.



PLATE 2


Fig. Page
STEPHANOPYXIS
1-2 Stephanopyxis turris (Grev.) Ralfs 18
3 Stephanopyxis corona (Ehr.) Grun. 18
CYCLOTELLA
4 Cyclotella meneghiniana var. stelligera Cl. and Grun. 20
5-6 Cyclotella operculata (Ag.) Kuetz. 20
7 Cyclotella comta (Ehr.) Kuetz. 20
8 Cyclotella meneghiniana Kuetz. 19
9 Cyclotella striata (Kuetz.) Grun. 19
10 Cyclotella stylorum (Br.?) V. H. 20
11 Cyclotella antiqua Wm. Sm. 20
12 Cyclotella meneghiniana var. stellulifera Cl. and Grun. 20
COSCINODISCUS
13 Coscinodiscus denarius A. S. 22
14 Coscinodiscus excentricus Ehr. 21
15-17 Coscinodiscus subtilis Ehr. 21
16 Coscinodiscus asteromphalus Ehr. 23
18 Coscinodiscus nitidus Greg. 21
19 Coscinodiscus nitidulus Grun. 21
20 Coscinodiscus excentricus var. perpusilla Grun. ? 21



PLATE 3


Fig. Page
COSCINODISCUS—Continued
1-11 Coscinodiscus radiatus Ehr. 23
2 Coscinodiscus velatus Ehr. 22
3 Coscinodiscus biangulatus A. S. 23
4 Coscinodiscus subaulacodiscoidalis Rattr. 23
5 Coscinodiscus lewisianus Grev. 24
7 Coscinodiscus argus Ehr. 23
8 Coscinodiscus lineatus Ehr. 21
9 Coscinodiscus marginatus Ehr. 22
10 Coscinodiscus oculus-iridis Ehr. 23
ACTINOCYCLUS
6 Actinocyclus ellipticus var. delawarensis n. var. 27



PLATE 4


Fig. Page
ACTINOPTYCHUS
1-4-6 Actinoptychus undulatus (Kuetz.) Ralfs. 24
2 Actinoptychus undulatus (inner stratum) 24
3 Actinoptychus heliopelta Grun. var.? 25
5 Actinoptychus vulgaris var. interrupta n. var. 24
POLYMYXUS
7 Polymyxus coronalis L. W. Bail. 25
AULACODISCUS
8 Aulacodiscus argus (Ehr.) A. S. 26



PLATE 5


Fig. Page
EUODIA
1 Euodia gibba Bail. 34
POLYMYXUS
2 Polymyxus coronalis L. W. Bail., zone view 25
EUPODISCUS
3 Eupodiscus radiatus Bail. 28
AULISCUS
4 Auliscus cælatus Bail. 29
5 Auliscus sculptus (Wm. Sm.) Ralfs 29
6 Auliscus punctatus Bail. 28
7 Auliscus (intermediate form between A. cælatus and A. sculptus) 29
8 Auliscus pruinosus Bail. 28
PSEUDAULISCUS
9 Pseudauliscus radiatus (Bail.) Rattr. 29
10 Pseudauliscus spinosus (Christian) Rattr. 29



PLATE 6


Fig. Page
ACTINOCYCLUS
1 Actinocyclus barkleyi var. aggregata Rattr. 27
2 Actinocyclus moniliformis Ralfs. 27
BIDDULPHIA
3 Biddulphia antediluviana (Ehr.) V. H. 32
5 Biddulphia reticulum (Ehr.) 33
6 Biddulphia favus (Ehr.) V. H. 31
7-8 Biddulphia alternans (Bail.) V. H. 33
TRINACRIA
9 Trinacria pileolus (Ehr.) Grun. 30
DITYLUM
4 Ditylum intricatum (West) Grun. 30
TERPSINOË
10 Terpsinoë americana (Bail.) Ralfs. 34
11 Terpsinoë novæ-cæsareæ Boyer 34



PLATE 7


Fig. Page
BIDDULPHIA
1-2-3-4 Biddulphia biddulphiana (Smith) 31
5 Biddulphia rhombus (Ehr.) Wm. Sm. 32
6 Biddulphia granulata Roper 32
7 Biddulphia turgida (Ehr.) Wm. Sm. 32
8 Biddulphia smithii (Ralfs) V. H. 32
9 Biddulphia lævis Ehr. 33
10 Biddulphia lævis Ehr. Sporangial frustules (260 diam.) 33
EUNOTOGRAMMA
11 Eunotogramma læve Grun. 33



PLATE 8


Fig. Page
RHABDONEMA
1-2-3 Rhabdonema arcuatum (Lyng.) Kuetz. 35
4-5-6 Rhabdonema adriaticum Kuetz. 36
7 Rhabdonema minutum Kuetz. 36
TABELLARIA
8-9-10 Tabellaria flocculosa (Roth) Kuetz. 36
11-12 Tabellaria fenestrata (Lyng.) Kuetz. 36
GRAMMATOPHORA
13-14 Grammatophora marina var. subtilissima (Bail.) V. H. 37
15-16 Grammatophora angulosa var. hamulifera (Kuetz.) Grun. 37
17-18 Grammatophora marina (Lyng.) Kuetz. 37
19-20 Grammatophora islandica Ehr. 37
21 Grammatophora serpentina Ralfs. 37
STRIATELLA
22-23 Striatella unipunctata (Lyng.) Ag. 38
24 Striatella interrupta (Ehr.) Heib. 38
ATTHEYA
25 Attheya decora West 38



PLATE 9


Fig. Page
LICMOPHORA
1-2 Licmophora flabellata (Carm.) Ag. 39
3-4 Licmophora lyngbyei Kuetz. 40
5 Licmophora ehrenbergii (Kuetz.) Grun. 40
6-7 Licmophora paradoxa (Lyng.) Ag. 39
8-9 Licmophora ovulum Mer. 39
10 Licmophora baileyi (Edw.) Grun. 40
11 Licmophora gracilis (Ehr.) Grun. 39
12-13 Licmophora gracilis var. elongata (Kuetz.) De Toni 39
14-15 Licmophora tincta (Ag.) Grun. 40



PLATE 10


Fig. Page
MERIDION
1-2-3 Meridion circulare (Grev.) Ag. 40
DIATOMA
4 Diatoma vulgare var. grande (Wm. Sm.) Grun. 42
5-6 Diatoma anceps (Ehr.) Kirchn. 42
7-8 Diatoma hiemale (Lyng.) Heib. 42
9-10 Diatoma vulgare Bory. 42
PLAGIOGRAMMA
11 Plagiogramma tessellatum Grev. 43
12 Plagiogramma obesum Grev. 43
13 Plagiogramma pygmæum Grev. 43
14 Plagiogramma wallichianum Grev. 43
EUNOTOGRAMMA
15 Eunotogramma læve Grun. 33
OPEPHORA
16-19 Opephora schwartzii (Grun.) Petit. 43
17 Opephora pinnata var. lanceolata n. var. 44
18 Opephora pacifica (Grun.) Petit. 43
FRAGILARIA
20-21 Fragilaria virescens Ralfs. 44
22-23 Fragilaria arctica Grun. 44
24-25-27-28-29 Fragilaria undata Wm. Sm. 44
26 Fragilaria undata Wm. Sm., var.? 44
30 Fragilaria construens (Ehr.) Grun. 45
31 Fragilaria harrisonii (Wm. Sm.) Grun. 45
34 Fragilaria capucina var. mesolepta Rab. 45
35 Fragilaria parasitica (Wm. Sm.) 45
36 Fragilaria sp. ? 45
37 Fragilaria linearis Cstr. 45
RHAPHONEIS
38 Rhaphoneis amphiceros Ehr. 46
39-40 Rhaphoneis amphiceros var. rhombica Grun. 46
41 Rhaphoneis belgica var. intermedia Grun. 46
SYNEDRA
32-33 Synedra radians Kuetz. 49