244 LABORATORY MANUAL OF HUMAN ANATOMY 



The Gray Matter. 



What is its form in cross-section? How does this vary at 

 different levels? Localize the central canal (canalis centralis) 



FIG. 101. 



Cross-sections through the human spinal cord, stained with carmine. 



A, transverse section at the level of C iii : Cg, commissura grisea ; Ap, apex columnse dorsalis ; Ca, 

 commissura ventralis alba ; Cc, canalis centralis ; Cm, commissura medullse spinalis ; Cm, cornu ven- 

 trale; Crp, cornu dorsale; Fna, funiculus ventralis; FnB, fasciculus cuneatus Burdachi; FnG, 

 fasciculus gracilis Golli ; Fnl, funiculus lateralis ; Fsla, flssura mediana ventralis ; Fslp, sulcus medianus 

 dorsalis ; k, tractus solitarius ; Pr, formatio reticularis ; .Ra, radix ventralis ; Rp, radix dorsalis ; Sg, 

 substantia gelatinosa Rolandi ; Sid, sulcus lateralis dorsalis ; Smd, septum medianum dorsale ; Spd, 

 septum intermedium dorsale ; Til, tractus intennedio-lateralis. B, transverse section at the level of 

 C vi : Prm, processus cervicalis medius cornu ventralis ; Til, columna intermedio-lateralis. C, trans- 

 verse section at the level of T iii : CCl, nucleus dorsalis Clarkii. D, transverse section at the level of 

 T xii : CCl, nucleus dorsalis. E, transverse section at the level of L v : m, medial cell group of the 

 cornu ventrale ; Iv, lateral ventral, Id, lateral dorsal, and c, central cell group. F, transverse section at 

 the level of S iii : m, medial, Id, lateral-dorsal cell group. G, transverse section through the lower part 

 of the conus medullaris at the level of origin of the N. coccygeus. ( After H. Obersteiner, Anleitung 

 beim Studium des Baues der nervosen Centralorgane im gesunden und kranken Zustande, III. Aufl., 

 Leipz. u. Wien, 1896, S. 227, Figs. 96-102. ) 



and the gray matter close to it, the central gray substance (sub- 

 stantia grisea centralis). In front of it is the anterior gray com- 



