PLANKTON OF THE GULF OF MAINE 
429 
c. 
May 5, 1915, station 10267 (fig. 121): 
Diatoms very abundant. 
*Ch£etoceras densum fully 50 per cent 
of the catch. 
C. May 5, 1915 — Continued. 
Chsetoceras criophilum. 
*Ch. decipiens. 
*Rhizosolenia semispina. 
*Thalassiothrix longissima. 
8. North Channel 
A. March 20, 1920, station 20078: 88 
Very few diatoms. 
Chsetoceras contortum. 
Ch. criophilum dominant. 
Ch. didymum. 
Coscinodiscus subbullien3. 
Rhizosolenia semispina S. 
B. April 15, 1920, station 20105: 
Diatoms abundant. 
*Chgetoceras decipiens dominant. 
*Ch. diadema dominant. 
*Thalassiothrix nitschioides also abun- 
dant. 
Bacteriosira fragilis S. 
*Biddulphia aurita. 
B. April 15, 1920 — Continued. 
Chsetoceras contortum S. 
*Ch. criophilum. 
*Ch. debile. 
*Ch. laciniosum. 
*Ch. teres S. 
*Coscinodiscus asteromphalus, 
*C. denarius S. 
*Nitschia seriata. 
*Pleurosigma stuxbergii S. 
*Rhizosolenia alata. 
*R. semispina. 
R. styliformis. 
*Thalassiosira decipiens. 
*Th. gravida. 
*Th. hyalina. 
Th. nordenskioldi. 
9. — Brown’s Bank 
A. March 13, 1920, station 20072. 58 
Scanty diatom and Ceratium plankton. 
Coscinodiscus asteromphalus dominant. 
Coscinodiscus sp. dominant. 
Chsetoceras diadema. 
Ch. debile. 
Ch. mitra. 
Thalassiothrix nitschioides. 
B. April 16, 1920, station 20106: 
Diatoms moderately abundant. 
*Chsetoceras contortum dominant. 
*Ch. debile dominant. 
*Ch. decipiens dominant. 
B. April 16, 1920 — Continued. 
*Ch. diadema dominant. 
*Thalassiosira gravida abundant. 
*Chsetoceras atlanticum. 
Ch. criophilum. 
*Ch. laciniosum. 
*Coscinodiscus asteromphalus. 
Coscinosira polychorda. 
*Rhizosolenia semispina. 
*R. setigera. 
*Thalassiosira decipiens. 
Th. hyalina. 
*Th. nordenskioldi. 
Thalassiothrix nitschioides. 
10. — Eastern Channel 
A. April 16, 1920, station 20107: 
Diatoms very abundant. 
*Chsetoceras contortum dominant. 
*Ch. debile dominant. 
*Ch. decipiens dominant. 
*Thalassiosira gravida dominant. 
*Th. nordenskioldi. 
*Biddulphia aurita. 
*ChEetoceras atlanticum. 
*Ch. criophilum. 
Ch. diadema. 
A. April 16, 1920 — Continued. 
*Ch. laciniosum (with endocvsts) 
*Coscinodiscus oculus-iridis. 
*Fragilaria oceanica. 
*Navicula frigida S. 
*N. vanhoffeni S. 
*Rhizosolenia alata. 
*R. semispina. 
*Thalassiosira bioculata. 
*Th. hyalina. 
*Th. sp. ? 
*Thalassiothrix nitschioides. 
t! Not examined by Doctor Mann. 
