198 



CAMPP.ELL, A. C, .Icanthicac or ThnrubUls. [ 



The Emu 

 1st Jan. 



New South Wales and in Queensland, go directly west through 

 Central Australia, and are found near the coast in W.A., 150 

 miles north of Perth. Buff under-coverts are found largely in 

 southern New South Wales, Victoria, and Tasmania. White 

 under-coverts appear in South Australia, and are found exclu- 

 sively in south-western Australia. These points, together with 

 two essential differences in the markings of the crown, give the 

 key to at least six races. Intergradations, however, existing be- 

 tween them, they rank as sub-si)ecies, not species. 



Only a tyro in ornithology would think there are no races or 

 sub-species among Acanthizcc. The study of sub-species, the de- 

 fining of their main characters and their geographical limitations 

 is just as important as the study of species. This branch of 

 ornithology has not yet been .seriously attempted. The material 

 in existing collections, both public and private, requires tabulating 

 and co-ordinating, and it is scientific research of this kind that 

 now awaits students. 



Of these small birds there are at least two genera. Gould fol- 

 lowed Cabanis in separating them into Ccobasilciis and AcautJiiza. 

 Present day observations support this. They resemble each 

 other only in size and in having brightly coloured upper tail- 

 coverts. They differ appreciably in wing formula, and in the 

 arrangement of colour pattern, especially in the tail. 



The following table compares the main features : — 



Acanthiza Geohasileits 



Habit 



Lives in 

 thickets 



and Feeds largely upon 

 the ground 



Wing formula 



. . Second primary less Second primar\- more 

 than twice length of than twice length 

 first : fourth longer of first : fourth 

 than third by about longer than third 

 2i mm. by about 1 mm. 



Shape of tail Rounded : outer fea- Squarer : outer fea- 

 thers about 5 mm. thers about 2 mm. 

 shorter than central shorter than cen- 

 tral 



Dark band Dn tail ..Narrow and sub- Wide and covering 

 terminal about half the tail 



Base of tail Dark in colour and Light or brightly 



not like upper tail- coloured like up- 

 covcrts per tail-coverts 



Throat Usually striated with Plain or minutely 



black fringed with brown 



Upper tail coverts . . Dark tones of brown Light tones yellow to 



tawny 



