ON THE GALL-BLADDER OF PARROTS. 263 
41. NOTE ON THE ABSENCE OR PRESENCE OF A 
GALL-BLADDER IN THE FAMILY OF THE PAR- 
ROTS.* 
In a former communicationt I had the opportunity of showing that Page 793. 
the generalization, founded upon the dissection of an insufficient 
number of genera, that the gall-bladder is wanting in the Columba, 
does not apply to Carpophaga, Lopholemus, or Ptilopus. On the 
present occasion I have to correct a similar error with reference to the 
Psittaci, because I have found a well-developed gall-bladder in speci- 
mens of Cacatua-philippinarum, Cacatua goffini, Cacatua moluccensis, 
and Calopsitta nove-hollandie, in which last-named species it is small 
and easily overlooked. _ 
In my earlier dissections I have not recorded the presence of a 
gall-bladder in any species of Parrot. That, no doubt, is because, it 
being absent in so many, I did not expect to find it. 
From the above facts it is highly probable that the presence of a 
gall-bladder in the Cacatuine will have to be included among the 
_ characteristic peculiarities of this subfamily. At the same time its 
persistence in them is in favour of the view that the Palzornithinz, 
as restricted by me,{ are but little different from the ancestral Parrots, 
and the Cacatuinz still less so. The primitive Parrots must have 
possessed a gall-bladder—because we know that this organ is present 
in the Cacatuinz, and consequently was not absent in the primitive 
species, as the probability that it should have been independently 
developed a second time is infinitely little. 
* “Proceedings of the Zoological Society,” 1877, p. 793. Read, Nov. 20, 1877. 
+ “ Proceedings of the Zoological Society,” p. 257. (Supra, p. 239.) 
t “ Proceedings of the Zoological Society,” p. 594. (Supra, p. 255.) 
