52 P. T. CLEVE. THE PLANKTON OF THE NORTH SEA, THE ENGLISH CHANNEL, AND THE SKAGEEAK. 



Mouth 



Date 



Tenii) 



Sal 



C. debilis Ol 



C. decipiens Cl 



C. diadema Ehb 



C. didymus Ehb 



C. Memalis Cl 



C. Sclitittii Cl 



C. scolopendra Cl 



C. soeialis Lauder 



C teres Cl 



Coscinodiscus eoncinnus W. Sm. . 



C. ociilus iridis Ehb 



0. polychordua Gbak 



Ditylum Brightwellii "West. . . 



Guinardia flaccida Castk 



Leptocylindrns danicns Cl. . . . 



Nitzschia seriata Cl 



Rhizosolenia delicatula Cl. . . . 



R. gracillima Cl 



R. semispina Hensen 



R. setigera Btw 



Skeletonema costatum Geev. . . 

 Thalassiosira gelatinosa Hensen 



T. gravida Cl 



T. Nordenskiöldii Cl 



Thalassiothrix Franenfeldii Geun 

 T. longissima Cl. & Geun. . . . 



Plankton-type 



I 



I 



2 



10 



3,70 



3,65 



23,58 



25,95 



I 



30 



II 

 9 



II 

 15 



2,10 

 26,27 



II 

 22 



2,45 

 27,34 



III 



III 



1 



8 



1,95 



■ 1,80 



22,62 



26,94 



C 



+ 





+ 



+ 



r 



r 



4- 





r 



+ 



+ 



r 







r 



r 



r 



+ 





r 



r 



III 

 11 



III i III 



21 I 29 



— I 2,10 



— 22,48 



IV 

 1 



IV 



7 

 3,95 

 27,22 



IV 



13 

 3,40 

 24,04 



rr 

 Tp 



r 

 (Tp) 



Tv 

 Nh 



+ 

 r 



+ 



c 



Tp 

 T 



Si 



c 



+ 



cc 



c 



c 



(Tp) 

 TNs 



Si 



r 

 r 



ce 

 cc 



Si 



Ns 

 (C) 



r 

 r 



c 



cc 



r 



Si 

 Ns 



r 



+ 

 ccc 



r 

 Ns 



+ 

 cc 



Ns 



c 



+ 

 + 



r 



+ 



r 



+ 

 ccc 



r 

 Ns 



+ 

 + 



r 

 ce 

 r 



Ns 



+ 

 + 



Ns 



r 

 + 

 r 



r 



+ 



r 



Ns 

 (Nm) 



Ns 

 {Nm) 



