ON THE ANATOMY OF THE PARROTS. 257 
posed, gave off a branch characterised by their abnormal arrange- 
ment. The continuation of the main stem, as well as the branch, 
shortly lost the ambiens muscle—the latter (and not the former), 
however, being represented at the present day in its unmodified 
form by the Arinw. Each of the two secondary branches persists as 
the Paleornithine and the Pyrrhurine respectively, they both 
branching dichotomously in an exactly similar manner, the former 
giving rise to the Stringopine and the specially modified Cacatua 
cristata and C. sulphurea, the other to the similarly modified Platycer- 
cine and Chrysotine. 
A method of formulation will assist in making this more readily 
intelligible. If the presence of two carotids, normally disposed, is 
represented by the figure 2, the abnormal arrangement may be re- 
presented by 2. Then, if the presence or absence of the varying 
structures be represented by + or —, the following table will express 
the characteristics of the different subfamilies :— P 
Carotids. | Ambiens. | Furcula. | Oil-gland. 
Palzornithine 2 - + + 
. 2 _ = - 
Cacatuine .. { L = ie s 
Stringoping ....... 2 oa ~ 
Aring ...... 2 7 ~ - 
Pyrrhurine ....... 2 oo - ~ 
Platycercine....... 2 = _ - 
Chrysotine .. 2 - - - 
Type form .. 2 ~ + rs 
The Paleornithine will thus be represented by the formula 
2, —,+, +; the Arine by 2, +, +, +; and soon. Plate [7] LXXI. 
will represent these facts in a more self-evident manner. 
Through the kindness of Prof. Flower and also from the death of 
the specimen presented by Mr. Murdoch to the Society, I have twice Page 596. 
had the opportunity of dissecting Stringops habroptilus. As a Parrot 
it is not so strikingly peculiar as many seem to think. Its wings are 
useless, and the carina sterni is correspondingly reduced, it is true ; 
but as points of classificational importance, I regard these as insignifi- 
cant. The points of special anatomical interest which it does possess, 
however, are particularly instructive. The proximal ends of the 
incomplete furcula are well developed, so much so that it might at 
first sight seem that their symphysial ends are only lost in correlation 
with the excessive reduction of the powers of flight; though this is 
probably not the case, because the allied similarly modified genera 
Euphema &c. do not keep to the ground. 3 
Further, in the Society’s specimen above mentioned, though the 
s 
Fo a Tl a 
