96 RUDOLF SÖDERBERG, STUDIES OF THE BIRDS IN NORTH WEST AUSTRALIA. 
Ecological. — The Artamus-species offer instructiv examples of the spread of 
the birds (cf. below and pages 17 and 18). The species above was commonly seen during 
the breeding season, hunting in companies, particularly in the neigh-bourhoods 
of the water-pools, at Mowla Downs, at the Fitzroy river, at Nooncanbah (WIiDELL), 
at Derby, etc. At the latter place it was, however, much more common in the 
middle of April, when I saw it there in flocks of 20—50. It was as general 
in May (the beginning of the month) at Meda, where the following species was 
common too, and in other places near the coast (»Bobbo yard»). But this species 
did not appear so frequently in Dampier land (Broome) in the beginning of the month 
of Aug. At this time the following species (A. personatus gracilis), on the other hand, 
was found in flocks in the bush. At Sunday Island, where ÅA. personatus gracilis 
was breeding, ÅA. leucorhyncus harterti was absent. 
On the 30th of Nov. and the l4th of Dec. I found two nests of the latter species 
at Mowla Downs. The former nest was built in the top of a tree, constructed in a 
simple way out of twigs. The other one was placed lower in the crown of a tree. 
Both of them were exposed on the branch, one of them with 4, the other one with 
2 young birds, almost full-grown. The parents flew anxiously »swirring» around the 
tree. The forms mentioned here (cf. the following species) are both apparently sta- 
tionary in Kimberley, although they wander a good deal in winter-time. 
Artamus personatus gracilis INGRAM. 
Math. handl. n:r 628. 4 SSF ad. Meda, Kimb. ??/5, 23/5 1911; 2 SS ad. Broome, Dampier I, "/s 1911; 
2 juv. (younger spec.) ibid. $/g 1911. 
Juvenal. — The younger specimen from Broome not in nestling plumage; a 
juvenal in the second year that has not yet obtained bright colours. 
Ecological. — This wood-swallow was seen by me at widely separated localities. 
During the breeding season it was rather rare at Fitzroy river and at Mowla 
Downs. At Sunday Island, on the other hand, it was more common in Jan., Febr., 
March. In the month of May it appeared in wandering flocks of about 20 members 
at Meda, and in Aug. in great flocks in the neighbourhood of Broome in Dampier 
land. It was observed, especially at Meda, that the birds lived in wandering flocks 
roaming from one place to another. In the beginning of my sojourn at Meda they 
were not found in that part, but about the 22nd of May smaller flocks arrived, 
which flew round and round over the steppe as well as over the wood. All the birds 
I have shot in one flock were males. The sexes certainly get together in separate 
flocks during the winter, for it is not very probable that the males are preponderant 
to such an extent. 
They kept specially to the blossoming Eucalyptus trees, where I saw them 
climbing in the clusters of flowers. 
The time for the appearance of the birds mentioned above seems to indicate 
that, like the former species, this species remains in Kimberley all the year. 
