748 PTILOPZDES—PUCKERIGE 
The figures here inserted serve to shew some of the differences 
of Pterylosis presented by various birds; but it will be obvious 
ARACHNECHTHRA 
and CINNYRIS 
oBscuRA. Dor- 
CinnyrRis CHLOROpyaIA. Ventral and dorsal aspect. sal tract. 
that a very long series would be required to exhibit even the 
principal types observable in the whole Class.1 
PTILOPALDES, a name proposed in 1872 by Sundevall 
(Tentamen, p. 102) for his second division (agmen) of the Class Aves, 
being the Birds whose young are thickly covered with down before 
their feathers grow: in 1873 changed (tom. cit. p. 158) to 
Dasypxdes, to prevent confusion with PstLopaDEs. 
PTILOSIS, the learned word for Plumage. 
PUBIS (properly Os pubis) or PUBIC Bones, the anterior, 
most ventral and slenderest of the three component parts of the 
PELVIS. 
PUCKERIGE (possibly connected with the A.S. puca, a goblin 
1 Since the time of Nitzsch additional descriptions of the Pterylosis of certain 
birds have appeared, but no special work on the subject, though it has by no 
means been exhausted, and such a work would be of considerable taxonomic 
utility if it were amply illustrated (little text being needed) and special attention 
paid to the numerous transitional forms that connect the chief types. <A great 
and revised mass of information is to be found, however, in Prof. Fiirbringer’s 
Untersuchungen der Morphologie und Systematik der Vogel. 
