PLATE XXI. 



#.»'•#'-• ;•.•■§ #*• .•♦♦■f "f 



• t f •;•'■•-•. M|'«*1l*-,f f 



!•#.«#'• •- INi»§'#i'* i »' t 

 m m m m :•'• •' mm^mm* f . #^9 



. • • tt. « «^ • m'%-m-^Mi^--^-m% 



Fig. 1. — Plankton-net Silk, Mesh of 

 No. 20, when new. X 23. 



Fig. 2. — The same silk after use in 

 the " Nansen " net, for a few 

 weeks. X 23. 



^M,'^€E!'- 



'^^'*S\r:- 



Fig. 3. — Zoo-plankton, consisting of 

 Oithona Helgolandica ; magnified. 



«« 





> - > '■-4. 











Fig. 4. — Mixed Plankton, consist- 

 ing of Diatoms, Nauplii, Poly- 

 chaet larvae, etc. ; magnified. 



