VOL. XV.] FIELD-NOTES ON THE BLACKCAP. 79 



male, and again in 1913, eleven days were sufficient for the 

 same operations, and although the female in this case may 

 have been overlooked for a day or so before she was first 

 noticed, nest building seems to have started practically upon 

 her arrival, an incident which appears to point to the possibility 

 of at least some individuals of this species mating before 

 they reach their breeding grounds. 



The record of 1920 is somewhat similar, one male arriving 

 on the exceptionally early date of March 31st, but no female 

 being seen until April 24th although the place was visited 

 every other day between those dates. 



The years 1910, 1911 and 1912 each have their early nest, 

 and are curiously consistent as to the date upon which the 

 first egg was laid, May 5th being the day in every case. 



Both birds do their share at building, and on April 22nd, 

 1 913, I watched a male very busily flying backwards and 

 forwards from a partially constructed nest, to a clump of 

 long dead grass stems which was the nesting material he was 

 using. He was exceedingly energetic, paying no attention 

 to me, and every now and then uttering snatches of his song 

 in an undertone from the bush in which the nest was hidden. 

 On the other hand, his mate resented my presence, and spent 

 all her time in scolding and trying to make up her mind to 

 return and go on with the work. 



Both sexes also share in the incubation of the eggs and the 

 feeding and brooding of the young. 



In 191 1 I was able to keep a nest under observation from 

 a hiding tent, for about two hours at a time, on four separate 

 days. The birds when building this particular nest had 

 made quite a departure from the usual run of nesting material. 

 Earlier in the year, about the middle of March, a friend had, 

 as an experiment, scattered a handful of clean cotton waste 

 of mixed colours, upon some brambles near the nesting site 

 afterwards chosen by these birds, and this strange material 

 had been liberally used by them. The only other birds we 

 could trace as making use of it were one pair of Chaffinches 

 {Fringilla coelebs). 



The following are notes made while watching from the 

 " hide," on May 29th, the 3^oung being at that date just nine 

 days old. " 5.30 a.m. Entered the hide, and the female 

 returned almost immediately, and fed the young with green 

 caterpillars. After she left the male arrived, but brought 

 no food. He, however, brooded the young, and it was 

 amusing to see the size he made himself, puffing out breast 

 and flank feathers, and raising those on his head. He was 



