OF THE SPERM WHALE. 
113 
the medulla closely, and the nerves immediately passing 
out through it at the lower part as they do at the upper, 
so that the cauda equina as it forms is on the outside 
of the dura-mater.” 
“ It would appear,” says Sir W. Jardine, a that the 
larger varieties have very small brains in proportion to 
the size of their bodies, whilst the smaller kinds again 
have very large and well-developed brains.” 
This observation, strengthened as it is by the state- 
ments of many celebrated naturalists, merely serves to 
corroborate the faithful and original descriptions of 
Hunter. Mr. Scoresby states that in a young specimen 
of the Greenland whale which measured eighteen feet in 
length, and weighed 11,200 pounds, the brain weighed 
only three pounds twelve ounces, which is only a three- 
thousandth part of the weight of the animal, wdiilst in 
man it weighs a thirty-fifth part. In a young rostrata 
seventeen feet long, Mr. Hunter found that the brain 
weighed only four pounds eight ounces. And Del a- 
lande states that in a rorqual eighty feet in length, the 
cranial cavity only measured thirteen inches by nine ; 
whilst Cuvier, in five examinations of the smaller genera 
of this order of animals, states that in the dolphin and 
porpoise, the brain weighed one thirty-sixth of the whole. 
The cranial cavity for the brain in the large male 
spermaceti whale which I examined myself at Burton- 
Constable, only measured in width about fourteen inches, 
in length ten inches, and in depth nine inches. 
The spinal canal for the reception of the medulla 
spinalis w r as, however, very large in proportion to the 
