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The Occipital Style of the Cormorant. — This style, which in skeletons is 
found articulated with the occiput, is in reality the ossified raphe of 
the temporal muscles (Owen, Anat., II, 93). Finding upon dissection 
of a young Cormorant the raphe but slightly ossified, I would make the 
following suggestion of its evolution. In some birds, especially those 
with small crania, the temporal muscles meet in the median line over the 
occiput. In the Cormorant we find this carried to an extreme, the mus- 
cles extending back for about an inch over the nape of the neck. This 
increase in the size, and consequently in the power of the temporal mus- 
cles, is evidently of great advantage to a bird of the Cormorant’s habits. 
But were the muscles not held in place, they would slide over the occiput 
with the first contraction. This could have been avoided by the muscles 
being attached to the vertebrre, or to a theoretical ligamentum nucha;. 
But such an origin would have bound the head in extension, a condition 
incomputable with the life of the bird. We therefore find the only other 
possible contrivance, a solid guy, extending from the cranium. This guy 
has been made by the conversion of the fibrous raphe into bone. In 
young Cormorants the raphe, though dense, is not ossified. Were the guy 
represented by a spinous outgrowth from the skull, motion of the head 
upon the neck would be seriously impaired, as the spine is fastened down 
to the neck by fascia and the skin. Therefore we find a ball and socket 
joint developed between the spine and the cranium. 
This beautiful adaptation of limited material to a given end points 
strongly to a Lamarkian mode of development ; its development by gradual 
selection is hard to understand. When we consider that demand upon 
a muscle leads to its increased size ; that bone is frequently formed in 
tendons— and such the raphe is — to meet mechanical needs ; that bursae 
form in connective tissue at points of friction, we see how all may be the 
direct result of demand upon the temporal muscles. Once given the 
structure, natural selection comes into play in the increase of Cormo- 
rants; but first cause and the means by which the results of a first cause 
are maintained should never be confounded. 
Finally, this bone, as the result of ossification of a common tendon of 
a pair of muscles, is an anatomical rarity. — J. Amory Jeffries, Boston. 
Ma$s ' Auk, I, April, 1C64. p. r<?C- /? /. 
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