THE MAMMALIAN NERVOUS SYSTEM 67 



tracts of the cord and brain has been gained by embryological 

 methods. Some functional systems of fiber tracts mature 

 earlier than others. Fetal spinal cords of man, pig, or any 

 other mammal taken at successive periods from the age when 

 myelinated fibers first appear up to birth and stained by the 

 Weigert method will demonstrate the sequence of myelina- 

 tion of the spinal tracts. See Barker ('01), pp. 424^437; His 

 ('04). 



5. Sympathetic Nervous System 



69. At this time the student should consult his reference 

 books and so become familiar with the general pattern of the 

 sympathetic nervous system and its relations with the cerebro- 

 spinal system. The sympathetic trunk and its connections 

 with the spinal nerves have already been seen (Section 41). 

 The following references are suggested: Barker ('16), Fig. 552, 

 p. 269; Cunningham ('15), pp. 679-682, 753-767; Edinger ('11), 

 pp. 96-105; Gray ('18), pp. 970-989; Herrick ('18), Chap. 

 XVI; Howell ('18), Chap. XII; Huber ('97); Johnston ('06), 

 Chap. XII; Langley ('00, 'OOa, and '03); Luciani ('15), Vol. 

 Ill, Chap. VI, pp. 359-378; Morris ('14), pp. 1026-1047; 

 Piersol ('16), pp. 1353-1375; Quain ('09), pp. 1-3, 13-20; 

 Sobotta ('11), pp. 238-246; Starling ('15), Chap. XIX; Stewart 

 ('18), Chap. XVII. 



6. The Medulla Oblongata 



70. The somatic sensory systems. (a) Here familiarize 

 yourself from the reference books with the somatic sensory 

 nerve-endings in the skin, subcutaneous tissues, muscle spin- 

 dles, tendons, joints, etc. See Herrick ('18), Chap. V; Barker 

 ('01)) pp. 361-421; Cunningham ('15), pp. 856-866; Piersol 

 ('16), pp. 1014-1020; Quain ('09), Vol. 3, Pt. 1, pp. 44-52; 

 and all works on histology. 



(b) Now review again the superficial landmarks of the ven- 

 tricular and lateral surfaces of the human medulla oblongata, 

 with special reference to the underlying functional columns (see 

 Sections 51 to 57). General somatic sensory fibers for cutane- 

 ous and deep sensibility of the head are found in the V, IX, 

 and X cranial nerves (Herrick ('18), Chap. XI), and the special 



