382 THE ZOOLOGIST. 



one with the period in which the warmth of the sun is first 

 beginning to be felt after the cold of the early morning, and the 

 other with the period in which the heat of the sun is most fully 

 developed, and that the two chief periods of food-activity, that 

 is morning and evening, coincide with the periods of greatest 

 activity in the earthworm. It is probable that the periods of 

 rest have become rhythmic habits, at least during the breeding 

 season, for they appear even when the weather is cold and wet. 



In the breeding quarters the variations of temperature, 

 occurring in May and June, have no apparent effect on food- 

 supply ; any disturbance that takes place being due more 

 probably to the other climatic conditions commonly associated with 

 temperature extremes. In hot weather the adults may become 

 dull and listless, but the condition does not last long owing to 

 the frequent recurrence of food — -and other activities. The chill 

 of night has evidently no more than a bracing effect on the birds. 

 One instance of " physiological misery " has come under notice. 

 An adult, after a spell of food-getting for the young in the early 

 morning, bathed about 4 a.m., and then went to " apparent " 

 sleep. The rigor which followed lasted a considerable time. 

 The young bear wide variations of temperature with equanimity. 

 During the first two days of life they are very sensitive to cold, 

 and are covered almost continuously. Thereafter, they have 

 to rub along on all sorts of days without additional warmth, 

 except during the coldest part of the night. They seem in- 

 different to hot sunshine, and I have not seen them shelter 

 under the wings of the parent when the sun is particularly hot, 

 as young Lapwings do in similar conditions. 



In summer no injurious effect of excessive moisture on adults 

 or young was discovered. Both are extremely hardy, and they 

 then enjoy an abundance of food, especially of earthworms. 

 Drought reduces the supply of these both for the adults and the 

 young. Worms may even be unobtainable. If worms cannot 

 be got, efforts are rarely made to bring other food from the 

 distant feeding grounds, and prodigious exertions are evoked to 

 supply the wants from the feeding area attached to the nesting 

 quarters. The sun-baked ground is hammered and pickaxed 

 with the powerful bills, the parents working feverishly, and for 

 long periods at a time, to supply the necessary quantity of food 



