322 



THE DISTRIBUTION OF AUSTRALIAN LAND-BIRDS. 



dicating this area as a well timbered and moist one, do 

 not pass into area 7. 



Area 3 contains 297 species, while area 7 contains 243 

 species, the bulk of which are derived from areas 3 and 

 6. The genus Sericulus is the only one peculiar to the 

 area. 



The Bassian sub-region in its low latitudes gradually 

 loses the tropical and sub-tropical forms carried on with 

 the stream from 3 into the northern part of area 4. Area 



4 lias its northern boundary between the Clarence and 

 the Hawkesbury Rivers. There the northern rich scrubs 

 cease, as do the fruit pigeons. 



It has 222 species, v/hich are more like those of area 

 3 than any other area excepting 5, which is simply a. 

 severed portion of 4, having an insular fauna, very 

 slightly modified. 



Of the 139 genera in area 4, four (i) are not to be 

 found in area 3; twenty-two (2) in area 6; and forty (3) 

 in area 5. This tends to show how the journey south 

 gradually loses from the list of each area a growing 

 number of genera. Twenty-five (4) are not to be found 

 in area 7. Very few genera are added to area 4 from 

 areas 7 and 6, and not any from area 5 (5), because there 

 is no available continuous area from which to draw. The 

 genus peculiar to area 4 is Pycncptilus. 



Area 5 but for Bass Strait would be the southern 

 faunal end of area 4. The insular area is evolving species, 

 though with one exception making no genera difterent 

 from those in area 4. 



Area 5 has 114 species. Of these, approximately. 100 

 are contained in the 222 species of area 4; thus about 100 

 have been lost to this last part of the course of the 

 southern emigration. The subsidence that formed Bass 

 Strait has not changed sufficiently the conditions of area 



5 to make a specially noticeable change in its fauna. 



(i) Calamanthns. Pycnoptilus, Monarcha. 



(2) e.g.. Atrichia. Psophodes, Oriolus. 



(3) e.g., Ptilonorhynchus, Piczorhynchus, Aegintha. 



(4) e.g., Menura, Pycnoptilus, Sphenura. 



(5) Tribonyx is accidental. 



