THE MAMMALIAN NERVOUS SYSTEM 45 



racic region and construct a diagram magnified two or four diam- 

 eters to illustrate the relations of the spinal cord, spinal nerves, 

 spinal ganglia, and sympathetic ganglia, with their peripheral 

 connections, to the body wall as seen in the transverse section. 



44. Spinal cord, gross structure. — Note in the intact human 

 spinal cord (medulla spinalis) the following external features: 

 the size, shape, length, segmentation, the cervical and lumbar 

 enlargements (intumescentise), ventral and dorsal nerve roots, 

 ganglia, membranes (meninges), ligamentum denticulatum. 

 Determine the location of the four transverse sections of the 

 human cord which have been distributed. Review from the 

 text-books the anatomical formation of the spinal column, the re- 

 lations of the cord segments to their respective vertebrae (Reid's 

 chart), the blood-supply of the spinal cord, its method of suspen- 

 sion in the vertebral canal, and, as far as possible, the relations 

 of the spinal nerve roots to their peripheral distributions. 



Cunningham ('15), Figs. 459-465, pp. 517-522, and pp. 685- 

 753; Morris ('14), pp. 752, 756, 771-775, 914, 919-921, 964-974; 

 Quain ('09), Vol. Ill, Part 1, pp. 58-68; Vol. Ill, Part 2, pp. 52- 

 148; Piersol ('13), pp. 1021-1028, 1054, 1278, and the following 

 pages; Reference Handbook of the Medical Sciences, 3d ed., 

 Vol. 7, article Spinal Cord; Sheldon ('18), chapters IV and V; 

 Spalteholz ('09), Vol. Ill, pp. 617-623; Toldt ('04), pp. 752-759 

 and 810, ff. 



45. Brain membranes. — Each student should be supplied if 

 possible with a sheep's brain and one lateral half of a human 

 brain. The intact human brain will first be examined by two 

 students at adjacent desks before being cut into halves. 



Study the brain membranes (meninges) and blood supply of 

 the sheep's brain, especially the circle of Willis (cf. Burkholder, 

 ('12), Plate IV) and the other vessels of the ventral surface, 

 and compare with the human. Review from the reference books 

 the form of the human skull and its foramina with their contained 

 nerves and blood-vessels; also the arterial and venous blood 

 supply and the lymph spaces of the brain and meninges. 



See Cunningham ('15), pp. 667-677 (meninges), pp. 900- 

 908, also pp. 969-976 (blood supply); Morris ('14), pp. 903- 

 924; Piersol ('13), pp. 730-753 (blood supply), pp. 1197-1209 

 (meninges); Quain ('09), Vol. Ill, Part 1, pp. 320-339; Sheldon 



