COUNCIL — APRIL 1912 — APPENDIX E — 94 — 



the more important species (cfr. Rapp. et Proc. Verb. XII, p. 80, C), especially of a 

 selection of the principal Copepods serving as food of fishes. 



Not only the adults of each species and sex, but also the different develop- 

 mental stages (eggs, nauplii and copepodites) must be determined. At the same 

 time the relative seasonal abundance of these different stages must be determined 

 by enumeration. It will also be necessary, wherever the opportunity occurs, to 

 investigate the distribution of each stage in relation to depth and physical condi- 

 tions by means of closing nets of the finest silk. 



The following species are particularly named for this research: Calanus 

 finrnarchicus and hyperöoreus, Pseudocalaniis elongatus, Euchaeta norvegica, Metridia 

 longa and lucens, Anomalocera Patersoni, Temora longicornis, Centropages typicus 

 and hamatus, Oithona similis, nana and plumifera, Microsetella atlantica, Acartia 

 longiremis and Clausi. 



When, in particular areas, other plankton-animals are so common as to be 

 of importance as fish-food, it is recommended that they should also be thoroughly 

 investigated on the above lines. 



It is proposed that during the cruise in May 1912 steps should be taken 

 towards carrying out this work. 



As regards certain of the above-mentioned Copepods, descriptions and figures 

 of all the developmental stages exist in the papers of Oberg and Krafft (Wiss. Meeres- 

 unters. Abt. Kiel). Reference should also be made to the work of Damas published 

 in the Publ. de Cire, and that of Paulsen in Medd. Komm. Havund., to Vols. I — II 

 of the Plankton Resume and to "Nordisches Plankton". 



2. By means of the investigations proposed in 1 valuable material will be 

 obtained in relation to the researches urgently recommended in Rapp. et Proc. 

 Verb. XII, p. 80, head B, the closer examination of the relation between plankton 

 and food-fishes. For this purpose it is above all things necessary to examine regu- 

 larly the contents of the stomachs of pelagic fishes and of the fish larvae simul- 

 taneously with the investigations of the plankton in the same water. 



3. It is urgently desired that quantitative determinations of the Micro- 

 plankton and Nannoplankton should be carried out on all opportunities when 

 trustworthy results of general importance can be excepted. It is recommended that 

 the centrifugal method should be applied to samples taken at different depths with 

 the water-bottle. As Prof. Gran has shown in Publication de Circonstance No. 62, 

 such water samples can be preserved with Flemming's solution for future exami- 

 nation of many of the most important species. 



