300 ORIGINAL ARTICLES. 



from the front, so as completely to disturb the real relative positions 

 of the cerebrum and cerebellum ; and the cerebral arachnoid and pia 

 mater have not been taken away. The internal dissection is almost 

 unintelligible. 



Tiedemann's two, more carefully drawn, figures represent an appa- 

 rently, well preserved, specimen, then, and probably now, in the Hunte- 

 rian Collection. From its small size, and from the imperfect develop- 

 ment of the convolutions, this brain was, most likely, taken from a very 

 young animal ; the cerebral membranes have been removed ; the 

 vertex is somewhat flattened ; the orbital surfaces have lost their 

 characteristic concavity ; the middle lobes have sunk asunder ; and 

 the cerebellum has, undoubtedly, been a little displaced backwards. 



Macartney's two figures were drawn from plaster casts of the 

 brain, taken before the cerebral arachnoid and pia mater were re- 

 moved — at least this is evident enough in regard to the basal view. In 

 size, these figures exactly correspond with the brain in my possession. 

 Owing, probably, to the unavoidable pressure and disturbance in the 

 casting, there is, in spite of the support afforded by the cerebral 

 arachnoid, even more subsidence of the parts at the base, than appears 

 in Tiedemann's corresponding figure. The orbital surfaces, though 

 tolerably concave, are too wide across their base ; the points of the 

 middle lobes have fallen asunder ; and the cerebellum has, clearly, slid 

 backwards from the hollow of the cerebrum, into which it would 

 naturally fit : moreover, the convolutions are somewhat convention- 

 ally drawn and, in certain parts, imperfectly and inaccurately repre- 

 sented. 



In the various figures given by Schroeder van der Kolk and 

 Vrolik, the brain is shown, entirely divested of its membranes ; the 

 convolutions are carefully and artistically rendered ; but all the above- 

 mentioned results of subsidence of the entire encephalic mass, both 

 laterally and from vertex to base, and the consequent distortion and 

 displacement of its parts, are particularly noticeable ; so that, on a 

 question of form and relative position, these now famous representa- 

 tions must come to be regarded as wholly unsafe guides. Barring a 

 certain primness of style, these figures are most carefully executed, 

 and they bear a critical comparison with our photographed views, 

 figs. 2, 4 and 5 ; but, the very closeness of resemblance between the 

 basal and lateral views and our figs. 2 and 4, shows that all have 

 equally been copied from nearly similarly sunken, or flattened, brains. 

 The width and evenness of the orbital surfaces, the severance of the 

 points of the middle lobes, the dragging back of the cerebellum, and 

 the sinking in of this last-named part between the hemispheres ; or, 

 viewed in its effect from above, the sliding of the posterior extremi- 

 ties of the hemispheres, forwards and sideways, over the cerebellum, 

 are all very obvious. One can note, especially, that owing, doubtless, 

 to circumstances connected with the state of the brain, or its mode 

 of preparation, suspension, or support, the unnatural lateral sepa- 

 ration of the cerebral hemispheres behind, is greatly exaggerated ; as 



