144 AUTHORITIES 



present per square metre of certain parts of the North Sea and 

 Baltic are given by Apstein in the Wissenschaftliche Meeres- 

 untersuchungen, Vol. 9, 1906, and later vols. Tables of the 

 occurrence and distribution of plankton organisms are published 

 by the International Council for the Exploration of the Sea, in 

 the Bulletin Trimestriel. Short accounts with bibliographies of 

 the methods and results of plankton investigations are given by 

 Jenkins and Dakin in the Transactions of the Liverpool Biological 

 Society, Vol. 15, 1901, and Vol. 22, 1908 ; and by Johnstone in 

 Conditions of Life in the Sea (Cambridge University Press, 1908). 



3. Oceanography. 



There is no English text-book, but Mill gives a good account 

 of the principal facts in The Realm of Nature (Murray, 1895). 

 The only exhaustive book on the subject is Kriimmel's Handbuch 

 der Ozeanographie (Stuttgart, 2 vols. 1907 and 1911). This book 

 is not translated. 



4. Ultimate food-stuffs in the sea. 



The main original sources are Raben's papers in the Wissen- 

 schaftliche Meeresuntersuchungen, Vol. 8, 1905, and Vol. 11, 1910. 

 Gran and Nathansohn also give some analytical results in the 

 Internationale Revue Gesamten Hydrobiologie, Vol. 1, 1908. An 

 account of the results obtained during the cruise of the German 

 ship 'Gauss' in the Antarctic is given by Gebbing in the Internat. 

 Rev. Hydrobiol, Vol. 3, 1910. 



5. Circulation of food-stuffs in the sea. 



See Nathansohn, Bulletin de Flnstitut Oceanographique, 

 Monaco, May, 1909. See also the work of Helland-Hansen and 

 Nansen on the Gulf Stream in high northern latitudes. This 

 memoir is very important. Reviewed in Science Progress for 

 Jany. 1910 and April 1910 by Johnstone. 



6. Nutrition of marine animals. 



The hypothesis that a saprozoic mode of nutrition is very 



