596 Mr. T. Carter on the Birds of [Ibis, 



One or two of the birds keep dropping out of sight, and 

 eventually one finds that the whole party has vanished in 

 the scrub. If a single bird could be chased out into open 

 country, a smart runner should l)c able to run it down, as 

 the birds do not seem capable of extended long flight. On 

 one occasion I had an adult male down in thick scrub 

 with a broken wing, and had the greatest difficulty in 

 catching- it. After a long chase I managed to get close 

 behind it just as it was disappearing under a large wattle- 

 bush, and, throwing myself down with extended arm, I thrust 

 it under the bush ahead of the bird, and by good luck swept 

 it clear outside with a mass of dead leaves and twigs. 



It needs two collectors to obtain good results, when in 

 chase of these very elusive adult males, which are even wilder 

 than those of Hallornis cyanotus. The song of both species 

 is very similar, a delicate musical "trilling" note, but it is 

 not so frequently uttered by the black and white as by the 

 blue and white species. 



The birds usually run along the ground with tails erect 

 at a surprising speed, but they sometimes hop. • They are 

 very skilful in flying perpendicularly into the air from the 

 top of a bush and catching small insects on the wing. 



My second visit to Dirk Hartog was unfortunately 

 delayed some weeks, owing to the fact that the only 

 steamer that calls at Shark's Bay had run on a reef in the 

 far north-west, necessitating repairs at Singapore, and so 

 the breeding-season of the black and white Wrens and 

 majority of the other species was missed. 



Immature birds, exceedingly small, but well able to take 

 care of themselves, were seen on 9 October, 1916, and on 

 many subsequent dates. 



Some male birds in immature plumage were obtained 

 about the same date, and, judging by their enlarged testes, 

 were, or had been, recently breeding. It may be mentioned 

 tiiat these birds have the largest testes, in proportion to 

 their size, of any bird that I have ever examined. 



On October 26 a non-breeding male was shot, which was 

 assuming the full plumage. In this species, as in Malurus 



