CA\AniA\ risllKlilKS EXJ'EDITIOS, Wl.',-!', 



185 



The prroiitcst contrast in avorafrc size is exhibited between stations 79 and 89. 

 Table P accordinjirly gives the hydrofrraphieal data for these stations as worked out by 

 Mr. Paul Bjerkan. 



TaijM': p. — Ilydrographical data for Acadia stations 79 and 89. 



2. Calanus hyperhoreus. This Arctic species is nearly as widely distributed in 

 our area as the preceding, but it is bound up with the deeper layers of water and in 

 that sense it is stenotropic, rarely appearing in surface hauls in these latitudes, ^[ore- 

 over it does not range so far south as C. finmarchicus. The Grampus found that, like 

 Euchaeta norvegica and Metridia longa, it was limited to the waters north of cape 

 Cod and was taken only at four out of twenty one stations in the gulf of Maine. At 

 Grampus sta.tion lOlCK) between cape Sable and Penobscot bay, opposite the mouth 

 of the Bay of Fundy, the vertical net from 90-0 fathoms contained 270 individuals of 

 C. hyperhoreus to 5400 C. finmarchicus, this being its plurinuim for the gulf of .Nfaine 

 (Bigelow, 1915, p. 293). 



According to Damas and Koefoed (1905) C. hyperhoreus is the commonest form 

 at the surface in the Greenland sea. In Canadian waters there does not seem to be 

 any regularity in its occurrence at or near the surface and each case would probably 

 need to be accounted for by reference to local and temporary conditions. Its presence 

 to the extent of 5 per cent in the deep surface haul with weighted net at Acadia sta- 

 tion 85 and not at stations 86 and 87 is perhaps significant in view of what has been 

 stated regarding this station (see above, table H). 



No male was observed in ai\v of the hauls. Sometimes there nuiy be a little 

 doubt regarding the identification of this species at stage IV with the three-jointed 

 urosome. The postcro-lateral angles of the forehody are not always so distinctly point- 

 ed as is usual. In such cases the do\ibt is at once removed by the examination of the' 

 fifth legs which although possessing coxal dentievdations in the subsequent stages, are, 

 unlike C. finmarchicns, devoid of them at stage IV in C. hyperhoreus. 



3. Calanus vulgaris. — Other species of Calaniis Avere met with at station* in or 

 near the Gulf Stream. Of these tne most remarkable was C. vulgaris which is not 

 mentioned in " 'N'ordisches Plankton" (v. Breemen 1908). The female of this species 

 has the postero-lateral angles of the forebody produced on each side as a ventrally 



6551—16 



