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in the neck, even to the median line. The deepest of the 

 dermal extensors of the fore-leg, is the Dermo Extensor 

 Brachialis Intimus. 



Above it, having a common insertion into the fore-arm 

 and an origin below the Dermo Extensor Brachialis Inti- 

 mus, about 15""". distance, are muscular fibres distinct 

 from the former. They form a flat muscle of about the 

 same width as, and shorter than the Dermo Extensor 

 Brachialis Intimus. It may be called the Dermo Extensor 

 Brachialis Inferior. Above this there is a third extensor, 

 shorter and broader than the others. Its origin extends 

 up under that of the Dermo Extensor Brachialis Inferior, 

 and it has a common insertion with the last mentioned 

 muscle, and may be known as the M. Dermo Extensor 

 Brachialis Superior. It is the most superficial of all the 

 layers of the skin muscles which act as extensors of the 

 fore-limb. Above it, however, the direction of the mus- 

 cular fibres of the Panniculus is the same as that of the 

 muscles already described. 



M, Dermo Cervicis Triangularis. 

 This muscle is of a broad, thin, triangular shape, and 

 connected at its insertion with the Dermo Extensor Brach- 

 ialis. It arises from the midline of the back, above the 

 anterior part of the Trapezius, and joins its fellow of the 

 opposite side. Its connection over the neck is by means 

 of a thin aponeurosis. It is inserted along with the other 

 dermal muscles of the fore-limb, into the front edge of 

 the ulna. The longitudinal muscle of the Panniculus, 

 which covers the fore-arm, has the same insertion. From 

 it a well marked slip can be separated having an insertion 

 into the Panniculus, alongside another muscle which ex- 

 tends over the external tube of the ear. Its position is 

 such that it is easily confounded with the muscles of the 



