STUDIES OE THE MACROCHIRES. 
307 
each side of the neck ; these connect the humeral tracts with 
the feathering of the head. 
Otherwise both the dorsal and ventral tracts of the Cedar- 
bird agree very well with the details of this important character 
as seen in such a Passerine form, e. g., as Motacilla alba. This 
fact may be better appreciated by comparing my drawings of 
the former (PI. XVII. fig. 1 a & b) with Nitzsch’s figures of the 
pterylosis of the latter *. 
12. The oil-gland is found to be nude, and this gland has a 
form such as is assumed among the great majority of the 
Passeres. 
Upon removing the integument, one of the most convenient 
anatomical points to be first examined is the method of insertion 
of the muscles of the patagium. In the case of a small bird such 
as we have in Ampelis, our present subject, I find an easy way to 
do this is to seize the elbow of the plucked pectoral limb with 
the thumb and index finger of the left hand, in such a manner 
that the palmar surface of the index finger is applied to the 
under surface of the patagium, and keeps it on the stretch. The 
thumb is opposed to this, and firmly holds the elbow-joint, and 
no more. We now make an incision, with the scalpel in our 
right hand, through the skin, down the line of the triceps muscle, 
and another at right angles to it, along the line of the ulna : 
then carefully dissecting back the triangular flap of integument 
thus outlined, the parts to be examined come nicely into 
view. 
13. In Ampelis the insertion of the tensor patagii longus and 
brevis are typically Passerine in character, as may be seen in the 
drawing here presented of these parts, which I made directly from 
my dissection (PI. XVII. fig. 2), ancl from Prof. Garrod’s excellent 
description, in his memoir upon the anatomy of the groupf, of this 
method of insertion, as we find it in nearly all Passeres. 
In A. cedrorum , however, we find another patagial muscle 
present in all Passeres which I have examined, which else- 
where I have named the dermo-tensor patagii, marking it dtp. in 
* Nitzsck’s •' Pterylography : ’ translated from the German by W. S. Dallas, 
and edited by P. L. Sclater, for the Ray Society. London, 1867 : Taf. iii. 
figs. 1 & 2. 
f Garrod, A. H., “ On some Anatomical Characters which bear upon the 
Major Divisions of the Passerine Birds,” P. Z. S. 1S76, pp. 506-519 (read 
June 6th, 1876). 
