140 P. T. CLEVE, DISTRIBUTION OF ATLANTIC COPEPODA. 







Mean 



tempera- 



ture. 



Mean salinity. 



Northern and 

 Southern limit. 



Distribu- 

 tion out- 

 side the 

 Atlantic. 



Calanus finmarchicus 

 C. hvperboreus . . . 





7.8 

 2.0 

 0.0 

 2.3 

 11.1 

 0.7 

 0.7 



5.0 

 (16.3) 



34.30 

 34.98 

 34.81 

 35.12 

 35.25 

 34.94 

 34.98 

 (35.95) 

 35.02 

 (35.82) 



30°— 81° N. 

 58°— 82° N. 

 65°— 74° N. 

 58°— 80° N. 

 42°— 69° N. 

 58°— 80° N. 

 62°— 71° N. 



(38° N.) 

 38°-78° N. 



M.P.I. 



M. 



M. 



Chiridius armatus . 

 Euchfeta norvegica . 

 Metridia hibernica . 

 M . lon^a 









0. minuta. .... 





It will be Seen, from the list, that the number of the species 

 is comparatively sraall, that the mean teraperature varies between 

 and 11.1, the mean salinity between 34.30 and 35.25. 



Among these species Calanus ht/perbo7'eus, Chiridius arma- 

 tus, ') Euchceta norvegica, Metridia longa and Onccea conifera 

 live as a rule far below the surface or are deep-sea species. 



Of the tricho-plankton copepods Calanus ßnmarchicus, Oncoia 

 conifera and 0. minuta have also been observed in the Mediter- 

 ranean, which seems to point to the conclusion that the Medi- 

 terranean raay receive water from the arctic regions. Calanus 

 fimnarchicus has the widest distribution, as it occurs also in the 

 antarctic seas and foUows the ciirrents from that region. 



The following list comprises boreal forms which are more 

 neritic than oceanic. All with the exception of Anomalocera 

 Patersonii enter the plankton of the Baltic. They have not 

 been seen south of 40° N. 



Acartia longiremis . . 



Mean 

 terape- 

 rature. 



Mean sa- 

 linity. 



Northern and 

 Southern limit. 



Distribu- 

 tion in the 

 Atlantic. 



Distribution 



outside the 



Atlantic. 



7.8 



33.99 



58°— 80° N. 





B. 







(6.00) 









Anomalocera Patersonii 



11.5 



34.17 



50°— 73° N. 



E. 





Centropages hamatus . 



9.7 



(1.0) 



33.58 

 (12.00) 



50°— 70° N. 



E. 



B. 



Pseudocalanus elongatus 



8.9 



34.53 

 (6.00) 



40°— 79° N. 



E.W. 



B. 



Temora longicornis . . 



10.8 



(-1.5) 



34.16 

 (18.00) 



40°— 70° N. 



E.W. 



B. 



^) According to G. O. Sars the same as Euchceta arniata BoECK. 



