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Show 1884.] MR. G. E. DOBSON ON CAPROMYS MELANURUS. 249 course, opens on its external free margin at the furthest distance from the ovary; each ovary lies close behind and external to the kidney, external to which the ovarian ligament passes outwards, downwards, and forwards upon the ribs and intercostal spaces, becoming lost in the peritoneal lining. The brachial plexus is formed from the fifth, sixth, seventh, and eighth cervical, and from the first dorsal nerve, as shown in the diagram (fig. 4). Superficial branches from the seventh and eighth Fig. 4. Fig. 4. Origins and connexions of the nerves of tbe brachial plexus. Fig. 5. Origins and connexions of the nerves of the lumbar plexus. ax, Anterior crural; a.th, Anterior thoracic ; cf Circumflex ; e.c, External cutaneous; i.c, Internal cutaneous; m, Median; m.sp, Musculo-spiral; ob, Obturator; rh, Bhomboid; s, Great sciatic; sb.s, Subscapular; spsc, Suprascapular. nerves unite to form the infernal cutaneous nerve (i.c), which is distributed as usual; and superficial branches derived from the sixth and seventh nerves unite to form the musculo-cutaneous (m.c). The ulnar nerve (ul) is formed by the junction of a large branch from the united branches of the first dorsal and eighth cervical nerves, and sends off a branch, which, with one derived from the seventh cervical, forms the median nerve (m). The musculo-spiral (m.sp), a large nerve, is formed under cover of the origin of the preceding nerves from branches from the seventh and eighth cervical nerves, and a small twig from the first dorsal. The circumflex (cf) is formed altogether from the sixth cervical, with which a communicating filament is derived from the fifth nerve. PROC. ZOOL. S O C - 1884, No. XVII. 17 |