Marine Diatoms llr 
Campylodiscus Thuretii Breb. 
Van Heurck Syn., Pl. 77, fig. 1; compare Micro. Journ., 1857, Pl. 1, fig. 41. 
Schmidt states in his Atlas Pl. 17 that according to Grunow this species 
was proven by Brebisson to include C. simulans Greg. (see second reference 
above), and the two are generally united. Deby however keeps them separate, 
figuring both in his Rev. Camp., Pl. 7, where they are quite dissimilar. But 
most authors also include here C. parvulus W. Sm., which, if the same, should 
replace both the other names. Without access to the actual specimens I must 
follow the general nomenclature. Certainly Brebisson’s original figure in Dit. 
Cherbourg, Pl. 1, fig. 3, is unlike any of these. 
In most of the dredgings, particularly from Stations 23, 41, 43), 48c, 43g. 
Chaetoceros Ehr. 2 
Chaetoceros atlanticum Cl. 
Gran Nord. Plankt., p. 64, fig. 74, Sch. Atlas, Pl. 337, figs. 1-2. 
Present in most of the plankton hauls, especially from Stations 12d, 13a-c, 18 
18d, 40d, and 56a. 
Chaetoceros boreale Bail. 
Gran Nord. Plankt., p. 73, fig. 87, Sch. Atlas, Pl. 325, figs. 5-6. 
Found only in the plankton haul from Station 13a-c. 
Chaetocercs constrictum Gran. 
Gran Nord. Plankt., p. 80, fig. 96; Sch. Atlas, Pl. 338, fig. 1. 
Found at Stations 6b and 12d, scarce in both. 
Chaetoceros criophilum Cast. 
Sch. Atlas, Pl. 342, figs. 1-3; Gran Nord. Plankt., p. 71, fig. 85, rather poor. 
This shares with C. decipiens Cl. in being most abundant in the plankton 
material examined. Found especially abundant at Stations 6b, 12d, 13a-c, 
25b-c and 40d. 
Chaetoceros decipiens Cl. 
Gran Nord. Plankt., p. 74, fig. 88; Sch. Atlas, Pl. 321, fig. 20 and Pl. 343, 
figs. 17-18. ' 
The most abundant of all the species found; especially noted at Stations 
6b, 12d, 13a-c, 25b-c, 40d, 42” and 56a. 
Chaetoceros Diadema (Ehr.) Cl. 
Gran Nord. Plankt., p. 84, fig. 102; Van Heurck Syn., Pl. 82 bis, fig. 6. 
Only the endocysts of this species were found, and in only one gathering, 
Station 56a, a plankton haul. 
Chaetoceros Jaciniosum Schutt. 
Gran Nord. Plankt., p. 82, fig. 99. 
Found at Stations 12d and 25b-c, not abundant. 
Chaetoceros Mitra (Bail.) Cl. 
Gran Nord. Plankt., p. 75, fig. 89. 
- This is called Dicladia Groenlandicus by Cleve in his Arct. Diat., Pl. 2, 
fig. 10. Found sparingly at Stations 6b and 12d, and in the dredging from 
Station 48c. 
Chaetoceros pelagicum Cl. 
Gran Nord. Plankt., p. 84, fig. 101; Sch. Atlas Pl. 348, fig. 1. 
Found only at Station 12d. It is thought by some to be a summer phase of 
C. laciniosum Schutt. 
