LISTS OF SPECIES BY STATIONS 



83 



Between stations 64 and 65 (o) 



A. January 3. 1929, 10'> to W' p.m.; 31° 52' S, 87° 51' W 



B. January 4, 1929, 0" to 2" a.m.; 31° 52' S, 87° 46' W 



40 species 



Location of tow 



Volume of tow, cm' 



A 



,S2 



B 

 32 



Location of tow 



Length of tow, miles 



A 

 0,6 



B 



2.4 



Acartia danac 



negligens 



Acrocalanus gibber 



gracilis 



Candacia norvegica 



simplex 



Clausocalanus arciiicornis. 



furcatus 



Clytemnestra rostrata . . . . 

 Corycaeus agilis 



crassiusculus 



speciosus 



Farranula carinata 



curta 



gracilis 



rostrata 



Macrosetella gracilis 



Megacalanus longicornis. . 

 Microsetella norvegica. . . . 

 Neocalanus gracilis 



Neocalanus robnstior. . . 



tenuicornis 



Oithona similis 



Oncaea curta 



media 



mediterranea 



minuta 



notopa 



similis 



tenella 



venusta 



Paracalanus parvus 



pygmaeus 



Pleuromamma gracilis. . 

 Pseudocalanus minutus. 



Sapphirina opalina 



Scolecithri.x danae 



Spinocalanus abyssalis. . 

 Undinula caroli 



darwinii 



These two surface tows were taken on the same night 

 about 5 miles apart. Twent>-nine species were taken in tow A, 

 just before midnight, and 31 in tow B, just after midnight. 

 Twenty of the species, or e.xactly half, were each confined 

 to one of the tows, and the other 20 were present in both tows. 

 The volume of the two tows was exactly the same although 

 tow B was four times the length of A. The copepod species 

 must ha\e been considerabh' more numerous just before mid- 



night than after, as would be expected. But the greater length 

 of the earh morning tow more than offset the superior abun- 

 dance in the one before midnight and produced 2 more 

 species. Oncaea surpassed Corycaeus and Farranula combined, 

 both in number of species and in abundance. Megacalanus 

 appears in both tows and e\idently does not alwa\s begin 

 its downward migration from the surface promptly. 



