KONGL. SV. VET. AKADEMIENS HANDLINGAR. BANI1 34. R:0 3. 5 



Clione limacina Pmrps. 74° N. 14 30 W. Dinophysh Vanhöffenii OSTF. 1 r. 



Beroe cucumis Fabr. 70° 55' N. 8" 30' W. and 74 N. Peridiniutn MiohaSlis Kins. 1 ?•/•. 



14° 30' W. P. ovatum 1'oucn. 1 r. 

 Cyttarocylis (dentic, var.) media Brandt 15 r, 30+. P. pallidum OSTF. 1 r. 



Ptychocjlis obtusa BRANDT. 15 ;•. P. pellucidum BBBGH. 30 r. 



CoUozoum inerme J. Mull. 4, 5, (5 c& Bacteriaslrum delicatulum CL. 1 >•. 



Halosphcera (small). 14 r. Chwtoceros diadema EHB. '25 and 27 r. 



Ceratixm furca Duj. 1 ?•. C furceiletua BAIL. 26 r. 



C. fusus Duj. 1, 2 r. C 1 , (borealis var.?) solitarius Cl. 5 >•. 



C. lineatum ElIB. 1 r. Rhizosolenia styliforrnis Btw. 3 r. 



C. (2n}>. rar.) longipes BAIL. 1 r, 2 f, 5 r. Thalassiosira gelatinosa Hensen. 14 r. 



C. tripos NlTZSCH. 2 r. T. gravida Cl. 10 +, 27 r. 



During thc passage towards Jan Mayen plankton from deeper water-sträta was col- 

 lected at 4 stations by means of hauls from different depths. Thc stations were so chosen, 

 that the slope from the 200 nietre plateau towards the northwest was firat examined, 

 then the region with a depth between 1,000 and 3,000 me tre and tinally the deepest 

 region. It is seen from the Table III that Calanus finmarchicus occurred abundantly in 

 nearly all samples. But there is a remarkable difference beween the plankton from the 

 station D and the others, therein that all samples from the said station, situated at the N.E. 

 of the Färöes, contained in great abundance chceto-planlcton. On both sides of this station 

 the bulk of the plankton was composed of Calamis Jinmarchicus and is thus to be classi- 

 fied as tricho-plankton. 



As is seen from tablcs II and III Calanus did not to any great extent occur at 

 the surface, but the chceto-plankton of the station D appeared at the surface from 64° 35' N. 

 1° 29' W. to 66° 55' N. 2° 55' W. The water containing ehcelo- plankton seems to have, as 

 a mighty tongue, forced its way through a bed of water containing tricho-plankton. 



The plankton from all the stations contain a small amount of species of southern 

 origin. Above the slope from the 200 metre plateau wc meet with some sj>ecies which 

 characterize the tri pos- plankton . Especially interesting was the extremely rare occurrence 

 of such a southern species as Ceratium reticulatum on 25 m. at the station B. The 

 samples from the station D contained Globigerina, CoUozoum inerme and rarely some other 

 species of the temperate Atlantic. It is remarkable that these southern forms appear to 

 occur chiefly in the deeper strata, as is clearly seen, especially at the station C, where a 

 thick-walled form of Globigerina occurred in abundance. Onccea minuta and O. conifera, 

 noted from the Mediterranean (the latter also from W. Greenland), are extremely rare in 

 the surface water of the temperate Atlantic, but of these at least the former occurs so con- 

 stantly in the tricho-plankton of the northern Atlantic that I consider it as probably be- 

 longing to the named type, and that its occurrence in the Mediterranean may be accounted 

 for by the influence of water of arctic origin. That such water goes so far as to the 

 Azores and the coasts of the Spanish Peninsula I have shewn in another paper. It is 

 thus not improbable that such water also may pass through the strait of Gibraltar. 

 The occurrence of Calanus jinmarchicus in the Mediterranean strongly corroborates this 

 hypothesis. 



