THE BIRDS OF AUSTRALIA. 
It is an extraordinary fact that there is a noticeable variation in 
coloration in this species with its restricted range, and I have named three 
forms thus : 
Colluricincla parvula alligator. 
“ Differs from C. p. parvula in its lighter upper-surface and longer bill. 
Alligator River, Northern Territory.” 
Colluricincla parvula conigravi. 
“ Differs from C. p. alligator in its larger size and lighter under- surface. 
Admiralty Gulf, North-west Australia.” 
Colluricincla parvula omissa. 
“ Differs from C. p. parvula Gould (from Port Essington : typical 
specimens in the British Museum) in its much greyer coloration above and 
in its much paler coloration below. Melville Island, Northern Territory.” 
I introduced the new genus name Conigravea for this group, and in my 
1913 “ List ” arranged C. turdoides Pucheran from Raffles Bay and C. p. 
alligator from the Alligator River as synonyms of the typical form from 
Port Essington, and allowed the Melville Island and North-west Australian 
forms as valid. 
Zietz recording birds from Melville Island and overlooking my description 
proposed 
Colluricincla parvula melvillensis. 
of w r hich he wrote: “Upper-surface much darker and bill longer than main- 
land specimens. Wing 95-101, bill 22-23 ; mainland specimen, wing 93, bill 
20 .” 
It would be interesting to know where the “ mainland specimen ” used 
for comparison was obtained, as the differences cited by Zietz do not agree 
with my definition above quoted. 
Again Campbell has written about the birds collected by McLennan 
at the King River : “ Two 3 <3 (wing 100 mm.), 1 $. Uniform olive-brown 
above, and the smallest of its kind.” 
At the present time it seems best to leave the names and forms as given 
in my 1913 “ List,” though later adjustment is possible thus : 
Conigravea parvula parvula (Gould). 
From Alligator River to Raffles Bay, 
Northern Territory. 
Conigravea parvula omissa (Mathews). 
Melville Island, Northern Territory. 
Conigravea parvula congravi (Mathews). 
North-west Australia. 
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