112 ESSAYS OF A BIOLOGIST 



tions of the sexes in birds, and have in my head a 

 number of pictures of their notable and dramatic 

 moments. These seem to me to illustrate so well the 

 emotional furnishing of birds, and to provide such a 

 number of windows into that strange thing we call a 

 bird's mind, that I shall simply set some of them 

 down as they come to me. 



First, then, the coastal plain of Louisiana; a pond, 

 made and kept as a sanctuary by that public-spirited 

 bird-lover Mr. E. A. Mcllhenny, filled with noisy 

 crowds of Egrets and little egret-like Herons. These, 

 in great flocks, fly back across the "Mexique Bay" 

 in the spiing months from their winter quarters in 

 South America. Arrived in Louisiana, they feed 

 and roost in flocks for a time, but gradually split up 

 into pairs. Each pair, detaching themselves from 

 the flocks, choose a nesting-site (by joint delibera- 

 tion) among the willows and maples of the breeding 

 pond. And then follows a curious phenomenon. In- 

 stead of proceeding at once to biological business in 

 the shape of nest-building and egg-laying, they in- 

 dulge in what can only be styled a honeymoon. For 

 three or four days both members of the pair are al- 

 ways on the chosen spot, save for the necessary vis- 

 its which they alternately pay to the distant feeding 

 grounds. When both are there, they will spend 

 hours at a time sitting quite still, just touching one 

 another. Generally the hen sits on a lower branch, 

 resting her head against the cock bird's flanks; they 

 look for all the world like one of those inarticulate 



