MIGRATION OF THE HERON. 



335 



cares of incubation ; after the eggs are hatched, he also assists in 

 providing for the young. 



When the young Herons are able to fly, they leave the nest and 

 cease to have their wants provided for by their parents. 



Fig. 132. — Common Heron and Egret. 



About the beginning ot August the time for migration has arrived, 

 the colony, possibly then amounting to 500 or 600 individuals, 

 prepare themselves to quit the heionry. The following year they 

 return, and their arrival. Lke their departure, takes place with great 

 regularity of date. It is remarked that the number of couples is 

 always nearly the same as that of the nests, so that each pair readily 

 find a resting-place ; the new geneiation must therefore leave their 

 progenitors to found a fresh colony. 



