(_b_) Lesions of the fasciculi graciles (column of Goll, 4) cannot, we believe, be recognized directly by positive symptoms. There are a few cases on record of primary (?) sclerosis of these columns, in which during life vague sensory symptoms had been noted, but we cannot build upon such data. Indirectly, however, we can in many cases diagnosticate degeneration of these fasciculi, reasoning from the data of pathological anatomy. Thus, for example, in advanced cases of sclerosis of the fasciculi cuneati (posterior spinal sclerosis) we know that in the dorsal and cervical regions of the cord the columns of Goll are in a state of secondary degeneration. After complete transverse division of the cord by injury, extreme pressure, or focus of myelitis, etc. the same (centripetal) degeneration exists above the lesion. The same remarks apply fairly to our clinical knowledge of the remaining parts of the æsthesodic system, columns of Clarke (6), and fasciculi ad cerebellum (5). We know absolutely nothing of lesions of the posterior horns (2) in their clinical and diagnostic relations. B. Lesions of the Kinesodic System.—Limits of the Kinesodic System.—In general this includes the antero-lateral parts of the cord. In a trans-section of the cord (vide Figs. 5 and 6) the following columns and fasciculi are recognized, their location and limits being made known to us by embryology, descriptive and pathological anatomy: (7) The anterior (ventral) nerve-roots emerging from (8) the true anterior columns or anterior root-zones; (9) the ventral (anterior) gray horns with their groups of ganglion cells; (10) the crossed pyramidal fasciculus, which is the caudal continuation of the cerebral motor tract of the opposite hemisphere; (11) the direct pyramidal column (column of Türck), which is the caudal continuation of the cerebral motor part of the hemisphere on the same side; (12) the antero-lateral column. Fasciculi 10 and 11 bear an inverse relation to each other—_i.e._ 11 is larger in proportion as 10 is smaller. [Illustration: FIG. 6. Diagram of a Transverse Section of the Spinal Cord through the Lumbar Enlargement: The æsthesodic system is shaded; the kinesodic system unshaded. Parts of the æsthesodic system: (1) Posterior nerve-roots; (2) posterior gray horns; (3) fasciculi cuneati (columns of Burdach, inclusive of posterior root-zones); (4) fasciculi graciles (columns of Goll, or posterior median columns); (5) ascending cerebellar fasciculi; (6) columns of Clarke. Parts of the kinesodic system: (7) Anterior roots; (8) anterior columns (inclusive of anterior root-zones); (9) anterior gray horns; (10) crossed pyramidal fasciculi; (11) direct pyramidal fasciculi (columns of Türck) [10 and 11 are the intraspinal prolongation of the cerebral motor tract]; (12) lateral columns of ill-defined limits and unknown functions; P. R., posterior roots; P. S., posterior septum; A. R., anterior roots; A. F., anterior fissure.]