230 Mr. W. P. Pycraft on the 
me with spirit-specimens of species hitherto undescribed 
. except from the skins. But for their help this paper would 
never have been written. I therefore take this opportunity 
of thanking them. Further, and finally, I am also in- 
debted to Mr. F. E. Beddard for the loan of spirit-specimens 
from the prosectorium at the Zoological Gardens. 
II. PreryLocrapny. 
Since, in some respects, pterylosis can most easily be 
studied in nestling birds, wherein the contour-feathers are 
just making their appearance, I have selected the nestling 
of Colius affinis for the following description. or the 
unexpected opportunity of so doing I have to thank Mr. D. 
Seth-Smith, who kindly presented two nestlings of that 
species to the Museum some little time since. These are 
here figured for the first time. 
For the sake of clearness the pterylosis of C. affinis will be 
first described in detail without reference to other species: 
after which the points wherein these differ one from another 
will be stated. 
Pteryla capitis (text-fig. 10, p. 231, pt.cap.).—The only 
adult examples of C. affinis which I have been able to 
examine I owe to the kindness of Mr. D. Seth-Smith, but 
unfortunately the pterylosis of the head-region was too much 
damaged for me to make out. From the examination of the 
nestlings, however, it would seem that the parietal apterion 
in this species is crescentic in shape, has the limbs of the 
crescent continued outwards into the ocular area, and is 
small in size. 
The upper jaw in the nestlings, I may remark, is of a 
lemon-yellow colour, while the under jaw is black; the 
inside of the mouth is also black, but the tongue is of a 
bright orange colour. 
The anterior nares are small oval apertures, piercing the 
membranous outer wall of the nasal chamber. 
Pt. colli dorsalis (text-fig. 10, pt.coll.d.).—This tract is of 
moderate width and just behind the head ceases to closely 
