THE OLDER STAGES i49 



pseudopodia of an amoeba. Many were of such irregular outline that they can only be described as 

 amorphous. In a number of instances they were seen to have gaps, resembling vacuoles, of clear water 

 inside them, giving them the appearance of having been hollowed out. 



They occurred right on, or very close to, the surface, or from i to 4 m. below, each individual patch 

 without exception seeming to consist of a narrow stratum or ' raft ' of densely crowded euphausians 

 no more than a metre or two thick. The patches in general were of more or less uniform thickness 



Fig. 15. Rough sketches of krill patches made by the late Dr E. R. Gunther, Weddell Sea, January to February 193 1, 

 the approximate dimensions of some of them being given in yards. The spacing of the patches has no relation to the 

 natural spacing. 



although variations in thickness did sometimes occur within individual patches. In colour consider- 

 able variation was noted, the degree of discoloration of the sea seeming to depend upon the depth of 

 water through which a patch was viewed rather than upon its own density. If right on the surface 

 a patch would present a brilliant red or vivid blood-red appearance while deeper down, at say 2 or 

 3 m., the colour would appear a dull rusty red or mahogany brown, fading away to a pale indeter- 

 minate cloudiness deeper. Even surface or near-surface patches would not always produce the charac- 

 teristic reddish discoloration. Sometimes it would be ochre-coloured or pale straw yellow, possibly 

 owing to variation in the pigmentation of the euphausians themselves. 



Matthews (1951) also remarks on the shallow draught of the congregating krill and provides us 

 with a vivid picture of the astronomically large numbers that must be concentrated in a single patch. 

 He is speaking here of a big one he saw near South Georgia. 'The shoal of krill, the food of the whales, 

 consisted of little shrimps about two inches long — they were only about half-grown^ — and reached 

 from the surface down to about two fathoms, the fish swimming underneath and feeding off the ceiling. 

 There must have been hundreds of tons of it, for the sea was thick with it like pea soup. ' 



1 They must in fact have been full grown. 



