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Muscues oF THE ANTERIOR EXTREMITY. 
Serratus magnus anticus (Pl. XI. XIII. i),—This muscle consists of three portions ; the 
first and anterior portion (PI. XIII. fig. 2. 7) arises by a short, strong aponeurosis from 
the last cervical rib, and is inserted into the lower edge of the anterior two-thirds of the 
scapula: the second and middle portion arises from the lower end of the second vertebral 
rib, near the attachment of the costal process, and from the anterior margin of the same 
rib, and is inserted into the lower edge of the posterior two-thirds of the scapula: the 
third, posterior and smallest portion (Pl. XI. 7) rises from the costal process of the third 
rib, and ascends to be inserted into the posterior extremity of the scapula. 
This muscle is a direct inspirator: by drawing down the scapula it depresses the 
sternum through the medium of the strong coracoideum, increases the angle between 
the vertebral and sternal ribs, and dilates the thoracic air-cells. 
Levator scapule (Pl, XI. XIII. k).—This seems to be the most anterior portion of the 
series of muscles which constitute the serratus magnus. Origin. Two flat fleshy strips from 
the inferior transverse and costal processes of the last and penultimate cervical vertebre. 
Ins. Into the inner and upper side of the middle third of the scapula. It depresses as 
well as draws forwards the scapula, and thus aids the serratus in the action of inspiration. 
Serratus anticus minor.—Origin. From the outer part of the costal process of the 
sternum, Ins, Into the posterior part of the base of the coracoideum. 
Trapestus (Pl. XIII. 7) —This flattened oblong quadrilateral muscle arises from the 
fascia, extending upon the back from the spinous processes of the posterior cervical 
vertebra, and is inserted into the conjoined extremities of the scapula and coracoideum. 
There is no representative of the rhomboidei. 
Latissimus dorsi (P|. XIII, m),—This muscle consists, as usual in Birds, of two por- 
tions, both of which have their origin from a continuation of the fascia, attached to the 
spinous processes, which gives attachment to the trapezius: the fibres of the smaller and 
anterior strip converge to their insertion: the fibres of the posterior and broader strip are 
slightly twisted, the posterior edge being folded inwards as they also converge to join 
the preceding, and to be inserted with it into the posterior and inner side of the proximal 
extremity of the humerus. 
Deltoides (Pl, X. XIIL. n).—This is a single long and narrow triangular muscle, of 
which the base is attached to the conjoined extremities of the scapula and coracoid, and 
to the capsule of the shoulder-joint; the apical insertion is into the upper and outer 
third of the humerus, which this muscle directly raises. 
Infraspinatus (Pl. XI. o').—A muscle which may be compared either to the infraspi- 
natus or teres major comes off from the lower margin of the anterior two-thirds of the 
scapula, passes behind the shoulder-joint, where it is closely attached to the capsule, 
and is inserted into the ipner and posterior part of the proximal end of the humerus. 
Musculi pectorales.—The pectoral muscles, which present their feeblest condition and 
