Page 195. 
324 ON THE ANATOMY OF CHAUNA DERBIANA. 
orum, with the normal origin from the secondary quills, has a different 
method of insertion, which has led M. A. Milne-Edwards to describe 
the muscle in the. common Fowl as a part of the coraco-brachialis © 
(brevis) in his superb work on fossil birds. 
In the genera Tetrao, Francolinus, Rollulus, Phasianus, Euplocamus, 
Gallus, Ceriornis, and Pavo, the muscle, instead of being inserted into: 
the scapulo-sternal fibrous band above referred to, after blending to a 
certain extent with the axillary margin of the teres, ceases by becoming 
fixed to a fibrous intersection about one-third down the coraco-brachialis 
brevis muscle. | 
In Francolinus clappertoni from among the Francolins, Coturnia, 
Odontophorus, Ortyx, Eupsychortyz, and Numida, the tendon does not 
go so far as the short coraco-brachialis, but ends either by simply join- 
ing the axillary margin of the teres, or by at the same time sending a 
tendinons slip behind it to the scapula. . In Argus giganteus the tendon, 
running from the elbow, turns round the axillary border of the teres 
to end by joining a triangular muscular fasciculus, attached by its 
base to the upper portion of the thoracic surface, which appears to be 
nothing but a differentiation-off of the upper portion of the last-named 
muscle. In the Cracide this insertion into the scapula is also found, 
but it is tendinous, like the upper element of the thoracic band above 
described in the Storks and Ohauwna; and in them there is also a 
second tendinous slip from the axillary margin of the coraco-brachialis 
longus (Plate [14] XII. fig. 5) (not the brevis). In the Megapodide also 
the attachment to the coraco-brachialis brevis is wanting, the tendon 
ending either by blending with the ¢eres-margin, or running on to the 
scapula. . 
In the Ducks and Geese among the Anseres the tendons under 
consideration, when they enter the thorax, run towards one another 
and join, after having expanded out, in the middle line, in front of 
the cesophagus, and behind the trachea. In the Swans this arrange- 
ment is not found, the tendons ending in the ciconine manner, or by 
running to the upper end of the scapula; and in this respect 
Sarcidiornis resembles them. 
From the tabular statement now exhibited (see p. 329) the nature 
as well as the presence or absence of this muscle can be determined in 
any special group of birds. The only Anomalogonatous birds in which 
i have found this muscle are the Coraciide. 
2. The presence or absence of a special muscular slip from the 
Biceps humeri to the Patagium. 
The biceps humeri, the main flexor of the arm, arises from the 
upper end of the coracoid bone, and from the upper portion of the 
