132 Anatomy of Sperm Whale Fetus 
Thus in both cases the head is rather less than one-quarter of the 
total length of the body, a proportion which is also that of the older 
foetus which I examined, and furthermore of that examined by 
Kikenthal. 
I should mention that the measurements given above of the younger 
feetus are taken along the long axis of both head and body. The 
length if taken from snout to tail, without regarding the flexure of 
the head upon the trunk, is only 97 mm., which agrees with the 
measurements taken by Mr. Chubb, i.e. 4 inches. These proportions, 
as I have already pointed out in my earlier paper, are different from 
those of the adult Cachalot, where the head is about one-third of the 
total length of the animal. It is noteworthy, however, that although 
in these younger festus the head is not smaller than in the older foetus, 
their general aspect is distinctly less like that of the adult Sperm Whale 
than is the festus of 20 inches. This appears to me to be due to the fact 
that the top of the head is more sloping in the younger foetus and 
that the body is rather deeper in proportion to its length than in the 
older foetus. 
I shall now proceed to describe in greater detail the several features 
which characterise the two fetus which form the subject of the 
present communication. The younger of the two (Pl. XXIII, fig. 1) 
is seen from the right side and the general appearance can be gathered 
from the figure referred to. The head is bent down at an angle 
approaching a right angle. The length of the head is 32 mm. or 
about 1} inches. The great flexure of the head is shown by the fact 
that a line between the snout and the base of the flipper is only 22 
mm. The side view of the head shows three features particularly 
worthy of comment. In the first place, the head rises abruptly in a 
straight line at right angles with the long axis of the head as in the 
other feetus and in the adult at times.* Secondly, attention may be 
drawn to the relatively large size of the eye, a feature which has been 
noted in other feetus of Whales, which seems to argue their descent 
from the more usual type of terrestrial mammal. Thirdly, the blow- 
hole and adjacent area is extremely obvious. 
EYE. 
With reference to the eye, its large size is seen to be due to the fact 
that the actual eye itself is more conspicuous than in the older feetus. 
* I have already commented upon the form of the head in the foetus and 
adult in my earlier paper and need not again enter into the matter. 
