204 THE PRODUCTIVITY OF THE SEA [PART II 



seas are sometimes impeded by the rank luxuriance of diatom life. 

 In the Antarctic we have a belt of ooze formed predominantly 

 by diatom shells extending round the southern hemisphere and 

 lOJ million square miles in extent : of course one must not urge 

 this as a necessary proof of the abundance of diatom life in 

 the sea since we do not know the rate of formation. But we 

 know from quantitative plankton researches how abundant these 

 microscopic plants are in Arctic waters. Nowhere did the Kiel 

 planktologists make such rich catches as in the KarajakaQord 

 on the north-west coast of Greenland (70° N. Lat.). In October, 

 1892, Vanhoffen made a catch of 225 c.c. of plankton with a 

 medium size quantitative net hauled up from 29 metres in depth ^. 

 Even during the months February — June, plankton was present 

 in the water under the ice. Numerous investigations made by 

 Lohmann, Dahl, Schlttt, and Kramer in the tropics shewed that the 

 catches made in these warmer seas were generally poorer than 

 those taken from temperate and polar waters"^. Just the same 

 result was obtained in the course of the Plankton-Expedition. 

 The reader should consult Schiitt's chart of the hauls ^ to see how 

 the quantity of the catch varies inversely as the temperature. 

 Relatively enormous catches were made in the cold water of the 

 West Greenland and Labrador currents, and in the up-welling 

 cool water off the west coast of Africa. But everywhere else (in 

 the warm equatorial streams, and in the Florida current) the 

 catch was much less ; and in the Sargasso Sea, where the tempera- 

 ture was uniformly high, over twenty catches were uniformly low 

 and contained the minimum amount of plankton caught during 

 the expedition. Yet who, from purely a priori considerations, 

 would not have anticipated that just the opposite results would 

 have been obtained ? Again one thinks of the Bay of Naples as 

 the place where good zoologists (like good Americans) go when 

 they die. Here if anywhere one would expect an abundance of 

 life in the sea. But just here we find a richly varied, but (in 

 mass) a scanty fauna and flora. Schiitt"* found that the plankton 



1 "Fauna u. Flora Gronlands," in Gronlands Exped. des Gesell. d. Erdkunde, 

 2. Bd., 1 Theil, Berlin, 1897. 



- Summarised by Brandt, " Stoffwechsel im Meere," 2 Abhandl. Wiss.Meeresunt. 

 Kiel. Kumm., Bd. vi. Abth. Kiel, 1902. 



3 Analytische Plaiikton-Studien, Kiel u. Leipzig, 1892. 



4 Ibid, 



