PROFESSOR WOOD ON THE NECK- AND SHOULDER-MUSCLES. 
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cervical fascia only. It lay considerably external to the origin of the lesser pectoral 
muscle, and was inserted internal to the scalenus anticus. Mr. Macalister considered 
it as acting from below upon the cervical fascia above (Notes on Muse. Anomalies, p. 7). 
He states that the muscle occurs in the JBalcenoptera rostrata, in the Seal, and in several 
Monkeys. 
Professor Turner, of Edinburgh, has also met with this muscle in two male subjects; 
in one on both sides, and in the other on the right side only. In the former it consisted 
of a long, ribbon-shaped muscle attached by a thin expanded tendon to the upper border 
of the fifth rib, immediately internal to the serratus magnus. The innermost part of 
this attachment was continuous with the intercostal fascia, and was attached to the rib 
at its junction with the cartilage. From the anterior surface of the fourth rib, close to 
the origin of the serratus magnus , a second and smaller origin proceeded. The muscle 
passed over the third and second ribs to be attached to the first rib immediately external 
to the tendon of origin of the subclavius. It was 6 inches long and f- of an inch broad 
at its widest part. In the subject in which the muscle was found on the right side only, 
it was attached to the upper border of the fourth rib, 2 inches external to the junction 
with the cartilage, ascended over the third and fourth ribs, and was attached above to 
the first rib f of an inch outside the origin of the subclavius (Journal of Anatomy and 
Physiology, May 1867, p. 251 ; and May 1868, p. 393, and figure). In the Liverpool 
Medical and Surgical Reports, October 1867, Dr. Roberts describes one of these muscles 
extending from the fourth to the first rib; and in Virchow’s ‘ Archiv,’ November 18th, 
1867, one is described by Bochdalek, Jun., under the name of “ supracostalis anterior ,” 
and another by Pye-Smitii in No. XLIII. of the same Journal (p. 142). 
Comparative Anatomy. — Professor Turner considers the supracostal muscle described 
by me to be the homologue of the thoracic prolongation of the mammalian rectus , which 
in the Cat, Otter, Beaver, Porcupine, and various other Mammalia reaches as far forwards 
as the first rib. But, as this accurate observer proceeds to say, “ In these animals, how- 
ever, the thoracic and abdominal parts of the rectus are directly continuous with each 
other, whilst in the human subject a break, corresponding in the first specimen to the 
fifth rib, and in the second to the fifth rib and fourth intercostal space, occurred ; but 
this break may be regarded as comparable to one of those transverse tendinous inter- 
sections invariably found in the abdominal portion of the human rectus abdominis, and 
which exists also in the recti of the greater number of Mammalia.” In his first paper 
“ On the Musculus sternalis ” {op. cit. 1867, p. 250) this author alludes also to a muscle 
described by Boerhaave and Portal, which was directly continuous with the thoracic 
attachment of the rectus abdominis, as undoubtedly to be regarded as the homologue 
of the anterior fibres of the mammalian rectus. In the case recorded by Boeriiaave it 
reached behind the great pectoral muscle as high as the junction of the third rib with 
its cartilage, and in that described by Portal as high as the second rib. This latter 
muscle is, however, evidently a formation distinct from the supracostalis, which pertains 
rather to the upper part of the thorax than to its abdominal portion. 
