558 Recently published Ornithological Works. [Ibis, 
Dr. Mjoberg, an entomologist, on an exploring and collecting 
expedition to Australia. He spent some ten months in the 
northern tropical portion of Western Australia, in the 
neighbourhood of Derby and Broome, and in this paper 
he gives us the results of his observations. Mr. Soderberg 
wisely devoted a great deal of his attention to such subjects 
as the movements or partial migrations of birds, due to the 
wet and dry seasons ; to the effects of discoloration produced 
by the extreme dryness of the summer season; to moult, 
which, like nesting, takes place at varying times of year, 
and is by no means so fixed to certain definite periods as in 
the temperate regions of Europe. He also made studies 
of the nesting-habits of many birds and the methods they 
adopt for combating their enemies, which appear to be 
chiefly egg-sucking lizards. All these matters are dealt 
with in a most suggestive and interesting way in the general 
portion of the paper. This is followed by the list of the 
species obtained, with notes on the juvenal plumage, moult, 
ecology, and other matters of interest. 
The paper is of considerable importance, and should not 
be missed by anyone who takes an interest in the problems 
of the desert fauna of Australia. It is written in English. 
Swarth on the genus Passerella. 
[Revision of the avian genus Passerella, with special reference to the 
distribution and migration of the races in California. By H. S. Swarth. 
University of California Publ. in Zoology, vol. 21, 1920, pp. 75-224; 
4 pis., 30 text-figs., including many maps.] 
The genus Passerella contains a number of Sparrow-like 
birds, commonly known in America as Eox-Sparrows. All 
the forms are included under one species, P. iliaca , of which 
Mr. Swarth recognises sixteen races, including the typical 
one. All the races breed in the far north or at considerable 
elevations, while the typical race has a very wide distribu¬ 
tion, breeding from Alaska to Newfoundland and visiting in 
winter the middle and southern States east of the Rocky Mts. 
The other fifteen breed along the western portion of the 
continent from the Alaska Peninsula through British 
