392 
that conclusions drawn from the relative weight of the brain 
and of the body are open to many objections ; as the weight 
of the latter must be influenced by the previous state of health, 
of fulness or of emaciation; the weight of the brain too must 
be materially affected by the amount of fluid it contains, or 
which may have escaped during the operations of removal and 
of weighing. Attention to the relative structure of the brain, 
therefore, is also necessary. The convolutions of the elephant’s 
cerebrum are very numerous, but rather small, and but few of 
the sulci are deep; the fissure of Sylvius is closed, and there- 
fore that numerous group of convolutions forming the ‘‘island 
of Reil” are absent; the grey neurine is not so thick as in 
man: on the whole, the cerebrum bears more analogy to that 
of the porpoise than to that of man, in whom the convolu- 
tions are large and numerous, the sulci deep, and many of 
them involuted over and over again. In man, too, the fissure 
of Sylvius is very deep, and when opened out presents a pro- 
digious number of convolutions ; his posterior cerebral lobes 
are extensive, and overlap the cerebellum; the grey neurine 
forms a thick investing lamina, the superficial extent of which 
is increased to a wonderful extent, and to a degree superior to 
what it is in any other animal. 
**J shall next place before this meeting a dissection of the 
proboscis or trunk of the elephant, the organ which forms 
the striking and characteristic feature of this group of ani- 
mals, no other possessing it in a perfect state, though in 
many it is rudimentary, as in the tapir and in the pig. It 
is essential to the existence of this animal, as the instrument 
for taking its food, and hence its name (zpo, Bookw). Its 
length varies from four to six feet, according to the height of 
the animal ; it is of a conical form, the base is attached to the 
nose, of which it may be regarded as a continuation, and is 
about two feet in circumference ; the apex is from four to six 
inches; the fore-part and sides are convex, and marked by 
rugged, transverse folds, which admit of extension and change 
of form; the posterior surface is flat and rough, and bounded 
