WATSON 



Fig. 25. 



y 



> ^ 



.\-5r"-_.."^^-^:::^Wj.?^.j>>-7^;?Si^2 



Fi-. 26. 



Group activity of Terns. 



Fig. 25. Noddies attacking a strange bird. 



Fig. 26. Peculiar behavior of the Terns when one of their number has fallen into the water. (Neither 



species swims with any success.) 



