28 THE USEFUL BIRDS 



rivers, and the swifts in a high stratum of air, this species, in 

 common with the House-Swallow, works the intermediate one. 

 That is to say, different kinds- of insects, which live in 

 different strata of air, have different kinds of Swallows to 

 keep them in subjection. There is also a Black and White 

 Swallow (Cheramceca) that keeps to the dry interior, doing 

 good duty by maintaining a balance in these parts. 



Nest. — Hollow of a tree limb, with decayed wood as a 

 base. 



Eggs. — White, spotted with reddish-brown at larger end, 

 more or less. Three to a sitting. Length, 0.75 inch ; 

 breadth, 0.5 inch. 



MASKED WOOD-SWALLOW, 



Artamiis persoiiatus, Gld. 



Ar'ta-mvs per-son-a'tas. 

 Artamos, a butcher ; personatus, masked. 



Artamus perso^tatus, Gould, " Birds of Australia," fol., vol. ii., 



pi. 31. 



Geographical Distribution. — Areas 3, 4, G, 7, 9. 



Key to the Species. — Under surface of the body beautiful grey ; 

 rump and upper tail coverts clear ashy-grey, like the back. 

 Male. — Face and tliroat jet-black. 

 Female. — Lighter in markings of head and throat. 



This bird is strictly insectivorous. At times it is most un- 

 popular with the beekeeper, whose winged helpmates suffer 

 considerable havoc wherever the Wood-Swallow has access to 

 his apiary. As a matter of fact, it is known in some districts 

 as the Bee-Martin. A market gardener informs me that the 

 Wood-Swallow renders signal service in the orchard by 

 destroying numbers of the odorous pear slug, which gives off 



