(I) Cervical vertebrae, or those between the skull and the first vertebra which is connected with the sternum by a pair of complete ribs.
Thirteen to fifteen cervical vertebrae.
In the cervical region the ribs are much reduced, fused with their verte brae and enclosing the transverse canal or foramen.
In many birds some of the thoracic vertebrae are more or less coOssified, in most pigeons for instance the 15th to 17th; in most Galli the last cervical and the next three or four thoracics are coalesced, &c. The pelvic vertebrae include of course the sacrum.
- A cervical vertebra from the middle of the neck of a Fowl; natural size.
The brachial plexus is formed by four or five of the lowest cervical nerves; the last nerve of this plexus often marks the boundary of the cervical and thoracic vertebrae.
In the region of the neck lateral strands pass through the transverse canal of the cervical vertebrae; but from the thoracic region onwards, where the cardiac branch to the heart is given off, each strand is double and the basal ganglia are successively connected with the next by a branch which runs ventrally over the capitulum of the rib, and by another which passes directly through the foramen or space formed between capitulum and tuberculum.
(I) The right and left carotids converge towards the middle and extend up the neck, imbedded in a furrow along the ventral surface of the cervical vertebrae.
There are five pairs of larger sacs belonging to the pulmonary system: - (1) prebronchial or cervical, extending sometimes far up the neck, even into the cranial cavities; the throat-bags of the prairie fowls (Cupidonia and Pedioecetes) are a further development; (2) subbronchial or interclavicular; (3 and 4) anterior and posterior thoracic or intermediate; (5) abdominal sacs.
Ardeae.-Piscivorous, nidicolous, waders; with complicated hypotarsus and with long cervical apteria.
Ciconiae.-Zoophagous, nidicolous, waders; with simple hypotarsus and without cervical apteria.
Nidifugous, waders; with simple hypotarsus and without cervical apteria.
The head is usually connected with the thorax by a distinct membranous neck, strengthened in the more generalized orders with small chitinous plates (cervical sclerites).
Ventral cervical sclerites III, Hind leg and metasternum.
Vertebrae: cervical, 7; dorsal, 18; lumbar, 5; sacral, 6; caudal about 12.
Vertebrae: cervical, 7; dorsal, 19-20; lumbar, 3; sacral, 4; caudal, about 22.
Unlike sloths, the megatherium has seven cervical vertebrae; and the spines of all the trunk-vertebrae incline backwards.
(b) Triarthridae; body with a pair of long cervical spines pointing distally and serving for leaping movements or to extend the body and make it too big for small enemies to swallow; Pedetes Gosse (no median spines); Triarthra Ehr., one postero-ventral spine; Tetramastix Zacharias, two unequal median spines.
The least specialized genus is Zapus, containing the jumping-mice of North America, with one outlying Siberian species, in which the five metatarsals are free, as are also the cervical vertebrae, the small upper premolar being retained.
Some of the cervical vertebrae are also united in at least the better-known genera.
It may be added that in the Oreodontidae the vertebral artery pierces the transverse processes of the cervical vertebrae in the normal manner.
Io -r I cervical, 12-11 thoracic, 2 lumbar, 5-6 sacral, and 20 or 21 caudal, with a total caudal length of the Berlin specimen of 7 in.
The cervical and thoracic vertebrae seem to be biconcave; the cervical ribs are much reduced and were apparently still movable; the thoracic ribs are devoid of uncinate processes.
In anatomy, it is, among other uses, applied to the second cervical vertebra, and in botany itmeans the stem.
The vertebral column consists of seven cervical, eighteen dorsal, six lumbar, five sacral, and fifteen to eighteen caudal vertebrae.
The bodies of the cervical vertebrae are elongated, strongly keeled, and markedly opisthocoelous, or concave behind and convex in front.
To these is attached the powerful elastic ligament (ligamentum nuchae, or " paxwax ") which, passing forwards in the middle line of the neck above the neural arches of the cervical vertebrae - to which it is also connected - is attached to the occiput and supports the weight of the head.
To it contributes the balance of the skull on the cervical vertebrae, while the human form of the pelvis provides the necessary support to the intestines in the standing attitude.
The number of vertebrae is - in the cervical region 7, dorsal 13, lumbar 6, sacral 2, caudal varying according to the length of the tail, but generally from 21 to 25.
The commonest seat is the groin, and next to that the axilla; the cervical, submaxillary and femoral glands are less frequently affected.