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BULLETIN OF THE LABORATORIES 
2d. Our preparations show with perfect clearness in Purkinje’s 
cells a basal process and one or more strong peripheral processes, 
which latter seem to us to be continuous with a system of transverse 
fibres lying in the molecular layer. The molecular layer contains 
sparsely scattered Deiter’s (“glia”) cells which stain deeply with 
haematoxylin and cells of the connective tissue system, 'which include 
those mentioned by Koelliker. 
3d. The fine branching processes of peripheral and basal pro- 
cesses of Purkinje’s cells are probably not nervous. 
4th. The “basket cells” of Koelliker are almost certainly of 
connective tissue character. 
5th Haematoxylin staining brings out quite evidently the large 
nerve cells of the granular layer, but we suspect that the ramifications 
described by Koelliker are, in this case also, the result of differentia- 
tion of the connective-tissue frame work of the cell. 
6th. Branching of the nerve fibres of the white central layer is 
rare. 
We are driven to reject the results of the Golgi method from the 
resemblance of the structures produced to those constantly encoun- 
tered and demonstrably the result of the intricate meshwork of con- 
nective tissue in the form of hollow sheaths enveloping the cells. 
Each nerve cell is loosely enveloped in such a sheath, which can be 
separated by proper treatment, and this sheath is produced in numer- 
ous directions into tubular or conical projections which may branch 
and ramify extensively. The same sheath may expand in a nodular 
manner to envelop another cell or embrace a fibre and may ultimately 
terminate in a number of brush-like fibrils attached to some membrane 
or fibrous strand. We believe this explanation is competent to account 
for many of the complicated structures described by Golgi. 
In the great majority of Purkinje’s cells, for example, we can 
trace a single strong process (these are numerous in the opossum), per- 
ipherad nearly to the surface, with little diminution of size, and perfect 
distinctness and with no lateral branches whatever. Hundreds of such 
cases are before us where a perfectly distinct uniform branch can be 
followed to near the surface and another of smaller diameter medianly 
through the granular layer. The nervous protoplasm in the cell and 
in both fibres is colored similarly. 
Furthermore, no rational interpretation of the structure described 
by Koelliker seems possible, while the arrangement we observe seems 
