LISTS OF SPECIES BY STATIONS 



23 



Station 12 

 August 5, 1928; 51° 40' N, 49° 32' W; bottom depth, 2792 m; 10 species 



Depth of tow, 111 

 Temperature, °C 

 Salinity, 0/00 



Calanus finmarchicus. . 



helgolandicus 



Eucalanus elongatus. . . 

 Microsetella norvegica. 

 Oithona simiHs 



Oithona spinirostris . . . . 



Paracalanus parvus 



Pareuchaeta tonsa 



Pseudocalanus minutus. 

 Scolecithricella minor. . . 



The temperature here was low at the surface and dropped 

 at the 50-meter level to 3?9, at the 100-meter level to 3?4. 

 Yet 8 of tlie 10 species were confined to the two lower levels 

 and onl\- the 2 species of Calanus were found at the surface. 

 The fact that these 2 species were found at the surface shows 



that some of them become positively phototropic at low 

 temperatures, but they were also abundant at the two lower 

 levels, showing that not all of them were so affected. This is 

 the second of the two Atlantic records for Pareuchaeta tonsa, 

 the first having been made at station 11, above. 



St.^tion 13 

 August 7, 1928; 46° 06' N, 48° 01' W; bottom depth, 126 m; 13 species 



Depth of tow, m 

 Temperature, °C 

 Salinity, 0/00 



Calanus finmarchicus 



helgolandicus 



minor 



Clausocalanus arcuicornis. 



Eucalanus elongatus 



Megacalanus longicornis. . 

 Metridia longa 



Microsetella norvegica. . 



Oithona similis 



spinirostris 



Oithonina nana 



Paracalanus parvus 



Pseudocalanus minutus. 



This was the shallowest station for the entire cruise, with 

 the bottom only 26 meters below the lowest tow. It was also 

 the coldest station, the temperature dropping at the 50-meter 

 level to 1?6, and at the 100-meter level to 1?2. Yet onlv 4 of 



the 13 species appeared in the surface tow, 8 in the 50-meter 

 tow, and all 13 in the 100-meter tow. There were many de- 

 velopment stages of Oithona similis and Oithonina nana at 

 the surface. 



