Ld 
336 THE LUMBAR ENLARGEMENT OF THE SPINAL CORD. 
are so entirely in agreement with his statements in all important particulars that I 
shall only notice some of the principal points. The large cells of the gelatinous sub- 
stance, which Clarke has described as occurring only in the fibrous band constituting 
the border of the substantia gelatinosa, are quite apparent in longitudinal sections, dis- 
posed at nearly regular intervals, usually in a single line just above each other, close 
to the entrance of the posterior roots into the gray substance, seeming to constitute a 
regular column connected with the posterior roots. With respect to the smallest cells, 
as well those of the whole posterior cornu as the substantia gelatinosa, I have not been 
able entirely to satisfy myself. Many of the smaller cells belong undoubtedly to the 
connective tissue, many are merely fragments of larger cells, and it is not improbable 
that some may be true nerve-cells still in process of development.  Fusiform cells* are 
often met with in the gelatinous substance, and are quite abundant in all parts of the 
posterior cornu, being frequently found in longitudinal sections. In the central por- 
tion of the caput the cells are mostly small, though large ones are occasionally seen, 
and just at the junction between cervix and caput large cells occur which are some- 
times quite thrust out into the white substance, embracing the longitudinal white fibres 
on all sides with their processes; in some few sections I have met with several cells in 
this position, forming by their processes quite an intricate network out among the 
white fibres. In the cerviz many large cells are met with, together with numbers of 
smaller size, and here cells are found more or less grouped together, belonging to 
Clarke’s posterior vesicular columns; for I cannot agree with Stilling that these cells 
disappear entirely in the greater part of the lumbar enlargement. t 
(C.) The Relation which Cells and Fibres bear to each other. — This subject I shall treat 
under the following heads: —(a.) The Connection of the Nerve- Cells with each other ; 
(b.) The Connection of the Cells with the Anterior and Posterior Roots ; (c.) The Con- 
nection of the Cells with the Longitudinal or White Fibres. 
. (a.) The Connection of the Nerve-Cells with each other. — Schroder van der Kolk¢ t 
* Figured by Clarke, Stilling, and Kölliker. 
t Stilling states, in opposition to Clarke, that the posterior vesicular columns, — “ (1.) Do not form uninter- 
rupted columns through the entire length of the cord. (2.) They do not enlarge in diameter in the lumbar 
and cervical enlargements, but disappear entirely in the greater part of these enlargements. (3.) Their great- 
est diameter is in the dorsal region between these enlargements.” In the dorsal region, according to my own 
observations, they seem to be collected into a compact group, completely circumscribed by a band of fibres, 
while in the lumbar region they are scattered over a very considerable space, the cells by no means entirely 
disappearing, however, even in the lower part of the lumbar enlargement. Clarke in his last paper, Philos. 
"Trans. 1859, has somewhat modified his earlier statements. 
i Bau und Functionen der Medulla Spinalis und Oblongata. Braunschweig, 1859. 
