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Show 1897.] MYOLOGY OF THE TERRESTRIAL CARNIVORA. 383 scalenus brevis lies ventral to the longus and rises from the 5th and 6th cervical transverse processes, and is inserted into the first rib dorsal to the brachial plexus. In Procyon (53) it rises from the 3rd, 4th, and 5th vertebrae, some of its fibres being continued into the supracostalis and a few into the rectus abdominis. As the names scalenus anticus, medius, and posticus give a wrong idea of the position of these muscles in quadruped animals, we have ventured to substitute those of ventralis, brevis, and longus, more especially as we are not quite convinced that tbe longus corresponds entirely to the human posticus (see fig. 6, p. 382). Muscles of the Dorsum of the Neck. -These muscles we find it more convenient to reserve until we deal with those of the trunk. Muscles of the Anterior Extremity-Pectoral Muscles. It is doubtful whether any satisfactory divisiou into pectoralis major and minor is possible in the Carnivora. Young, in his description of Viverra civetta, says that " the pectoralis minor is wanting as usual in Carnivora" (VIII.). On the other hand, Shepherd and Testut (XXIII.) describe a definite pectoralis minor in the Black Bear ( X X ) . Occasionally some of the deeper fibres of the mass are inserted into the region of the coracoid process and shoulder-joint, but they are not constant even in different specimens of the same animal. As a rule four fairly distinct parts may be distinguished, and the most satisfactory mode of description seems to be to take an animal like the Racoon, wdiich occupies an intermediate position in the Order, as a type and to notice the chief differences in other animals. In Procyon lotor (5'A), then, one portion (a) rises from the anterior half of the sternum and is inserted into the pectoral ridge in the middle two-fourths of the humerus, the fibres running transversely (this is Windle's Superficial Mauubrial factor) (XLVII.). Another part (j3) comes from the anterior quarter of the sternum, deep to the last, and is inserted into the humerus from the great tuberosity to the middle ; the fibres of this part run forward and outward (Windle's Deep Manubrial) (XLVII.). The third part (y) rises from the middle of the sternum to the sterno-xiphoid articulation; it is inserted deep to the last into the second quarter of the humerus and is joined on its deep surface by the abdominal and dorsal panniculus, with which it is more or less continuous. This part represents all that there is of the abdominal pectoral or pectoralis quartus, and corresponds to Windle's Superficial Gladiolar (XLVII.). The fourth part (S) may possibly represent the pectoralis minor ; it is the deepest layer of all and rises from the middle two-fourths o£ the sternum, running obliquely forward and outward to the head of the humerus and capsule of the shoulder (Windle's Costal factor) (XLVII.). It will be noticed that each of these last three layers is deeper than the one before it at its insertion. The proportions and amount of distinctness of the different parts of the pectoral vary infinitely and are seldom alike in two specimens of |