14F Canadian Arctic Expedition, 1918-18 
Coscinodiscus Payeri Grun. 
Grun. Diat. F. Jos. Land, Pl. 3, figs. 12-14. 
Found only at Station 23, there rather frequent. 
Coscinodiscus polycanthus Grun. var. baltica Grun. 
Grun. Diat. F. Jos. Land, Pl. 3, fig. 17. 
Found only at Station 20b-c. 
Coscinodiscus radiatus Ehr. 
Grun. Diat. F. Jos. Land, Pl. 3, fig. 1. 
The specimens were the variety which Grunow calls glacialis on the above 
plate and var. borealis on p. 72. Found at Stations 23 and 430. fe 
Coscinodiscus radiosus Grun. 
Jan. Gaz. Exp., Pl. 5, fig. 9; Sch. Nordsee Diat., Pl. 3, fig..42, no name. 
The above are identified in Ratt. Rev. Cose., p. 521. Found at Station 29g. 
Coscinodiscus septentrionalis Grun. 
Grun. Diat. F. Jos. Land, Pl. 4, fig. 33. . 
Grunow expresses doubt of this being a variety of C. lacustris Grun., which 
latter is probably a Cyclotella. Abundant in many of.the dredgings, particularly 
at Stations 20b-c, 28, 41, 41c, 48a, 48b and 438c. 
Coscinodiscus subglobosus Cl. and Grun. 
Grun. Diat. F. Jos. Land, Pl. 4, figs. 19-20; Sch. Atlas, Pl. 58, fig. 44, 
unnamed. : 
This is a strictly Arctic species. Found in dredging at Station 430. 
Coscinodiscus subtilis Ehr. 
Sch. Atlas, Pl. 57, figs. 11-16. ; 
A species of universal distribution and great variability. Found at Stations 
23, 27s, 43a and 43d. 
Coscinodiscus tuberculatus Grev. 
Sch. Atlas, Pl. 57, figs. 40-42; Grun. Diat. F. Jos. Land, Pl. 3, fig. 29. 
Grunow expresses doubt of his specimen from Franz Josef land being 
this species because it had hitherto been found only in a fossil state. The dis- 
covery of it here confirms Grunow’s identification. Found at Station 29g. 
Coscinodiscus tubiformis Temp. and Brun. 
Temp. and Brun, Diat. Jap., Pl. 7, fig. 6. 
I suspect this to be nothing but a small, robust specimen of C. marginatus 
Ebr. with a very wide girdle. I have found it frequently in cold marine waters 
as well as here. Found in a plankton haul, Station 43/. 
Cymbella Ag. 
Cymbella arctica Lager. 
Sch. Atlas, Pl. 10, fig. 12. 
The type specimen was found at Spitsbergen; those found here agree 
perfectly with the type. Station 27s. 
Cymbella gastroides Kitz. 
Sch. Atlas, Pl. 9, figs. 1-2; Grun. Diat. F. Jos. Land, Pl. 1, fig. 7. 
This species occurs recent and fossil, fresh-water and marine. Found in a 
dredging at Station 28. 
Denticula (Kiitz.) Grun. 
Denticula elegans Kiitz. 
Van Heurck Syn., Pl. 49, figs. 14-16. 
Normally fresh-water, this species also occurs iti brackish and marine 
gatherings. Found in chains of eight or more frustules in a plankton haul from 
Station 43f. 
