186 H. R. OCTAVIUS SANKEY. 



as soon as the brain is removed from the skull, or at latest 

 on the day following, the best fluid to place it in to preserve 

 it is a strong solution of ammonium acetate of a sp. gr. of 

 about 1040. This solution does not harden the brain to any 

 marked degree, nor does it crystallize out during desiccation, 

 nor by its deliquescent properties does it prevent the brain 

 from drying. The brain, indeed, may be preserved in this 

 solution for many weeks in a suitable state for the process. 

 It should, however, be cut into pieces not larger than wal- 

 nuts before being placed in the fluid, and should be soaked 

 in water for several hours before the sections are made, other- 

 wise it will be found that the brain has for some reason 

 become much more adhesive, and sections when made cannot 

 be removed from the knife without laceration. 



Part II. 



By means of the process of which I have now given the 

 principal details, I have carefully examined many brains, 

 with the view of testing various views which have been 

 published at diff'erent times in connection with the Histology 

 of the Brain and Nervous Centres. I propose here to give 

 some of the results which my study has afl"orded me, and in 

 the present communication I intend to confine my observa- 

 tions to the structure of the cerebellum ; since my mode of 

 investigation enables me to confirm some observations made 

 originally by Dr. Obersteiner^ concerning it, which, so far as 

 I am aware, have not yet met with substantiation, and which 

 do not even appear to be accepted, if I may judge from the 

 fact, that though Dr. Meynert, writing in ' Strieker's Com- 

 parative and Human Histology,' alludes to several points 

 mentioned in the paper quoted, yet omits all mention of those 

 points to which I am about to allude. 



Dr. Obersteiner, in speaking of the pure grey or outer 

 layer of the cerebellum, says : — " The neuroglia of this layer 

 is scattered over with round and elongated nuclei of a 

 diameter of O'OOT mil. The latter scarcely present any cell 

 around them, and probably belong to the connective tissue. 

 A clear border surrounds the round nuclei, which is either 

 round or angularly drawn out. It is these nerve-cells with 

 processes which unite themselves to the end branches of 

 Purkinje's cells." I find that if in a section made perpen- 

 dicularly to the surface of the cerebellum, and at right angles 

 to the lamellae, one of Purkinje's cells be brought into 

 view under a magnifying power of about 600 diameters and 



1 " Beitrage zur Kenntniss vom Bau der Kleinhirnriude," 'Sitzungsbericht 

 d. K. K. Acad, der Wisseuscbaft/ Band, h., Heft i. Wien. 



