46 
Length of wing 425 to 4:15 inches, tail 3-35 to 3:1 inches, culmen 1:0 to 0:85 inch, tarsus 1:4 
to 1:8 inch; bastard-primary projecting about 0:1 inch beyond the primary-coverts, its exposed 
portion measuring 1:0 to 0:85 inch. 
Young in first plumage are unknown. Females are believed to resemble males in colour. 
In spite of the fact that Péron's Ground-Thrush has the underparts unspotted, and the black 
bands across the ear-coverts as in. Geocichla princii, and that it differs so widely in the colour of the 
underparts from Geocichla erythronota, there are reasons why it should be regarded as most nearly 
allied to the latter species. That they are the only two Ground-Thrushes which are orange-chestnut 
above from crown to upper tail-coverts is, perhaps, not of much importance; but that no other 
Ground-Thrushes have white margins to the unemarginated outer webs of the primaries, and have 
white at the bases of the outer webs of the secondaries, suggests the probability that these characters 
have been inherited from common ancestors and have not been independently acquired. 
The figure on the Plate to the left of Geocichla erythronota represents an example in my 
collection; it was obtained on the island of Timor by Mr. Wallace during his celebrated voyage to 
the Malay Archipelago. 
Vieillot's type was figured in 1855 (Pucheran, ‘ Archives du Musée d’Histoire Naturelle,’ vii. 
plate 19) and is sufficiently well drawn and coloured to leave no doubt as to the identification. 
