Heath's practical anatomy : a manual of dissections / [Christopher Heath].

  • Heath, Christopher, 1835-1905.
Date:
1893
Catalogue details

Licence: Public Domain Mark

Credit: Heath's practical anatomy : a manual of dissections / [Christopher Heath]. Source: Wellcome Collection.

    682/800 (page 660)
    Fig. 300. bottom of the median fissures are the anterior and posterior commissures. The Spinal Nerves (Fig. 297) are thirty-one in number on each side of the cord. Each nerve has been seen to arise by two roots, the posterior (except in the first nerveX^ being larger than the anterior. The posterior roots have each a ganglion, which is generally ^^l^^^^ the intervertebral foramen ; and imme- diately beyond the ganglion, the anterior or motor and posterior or sensory roots unite to form a spinal nerve of mixed endowments. The first and second cervical, with the sacral and coccygeal nerves, are exceptions to the general rule as regards the position of the ganglia. The ganglia of the upper_ two cervical nerves lie__upon_ the arches of the atlas and axis, at which point the roots of the nerves unite. The ganglia of the sacral and coccygeal nerves are within the sacral canal. Each spinal nerve divides into an anterior and a posterior trunk, the anterior being the larger throughout, except in the 1st and 2nd cervical nerves, Avhere they are of smaller size than the posterior. The majority of the sjDinal nerves divide^ outside the intervertebral foramina^ 'But in the first cervical, the last sacral, and the coccygeal nerves, the division takes place within the dura mater ; and the upper Fig. 300.- The cauda equina, seen from behind (from Hirschfeld and Leveille). 1. Root of 12th dorsal nerve. 4. Fourth sacral nerve. 2. Dura mater laid open. 5. Fifth and sixth sacral nerves. 3. Filum terminale.