of Edinburgh , Session 1875 - 76 . 
109 
of the epithelium-cells lining its crypts has convinced me, that 
they are not a pavement epithelium, in the sense of being 
squamous cells, but have an intermediate or transitional form 
between the columnar epithelium and the tesselated epithelium. 
In the Narwhal, again, the cells are cylindrical, as in so many 
mammals, so that I believe the Cetacea to offer no exception to 
the view that these cells are a secreting epithelium, and they 
doubtless elaborate a secretion for the nourishment of the foetus. 
From the fact that the utricular glands had a much greater 
calibre in my specimen than in the one belonging to Dr Thomson, 
one may infer that even after the crypts are fully developed the 
glands still play a part in foetal nutrition. 
The foetus in my specimen had an almost uniformly purplish-grey 
colour, but with a patch of yellowish-white on the belly near the 
anus. The snout was rounded; the fissure of the mouth 1J inch 
long; eye-slit inches behind the snout, and surrounded by a 
faint circle; ear orifice very minute, 3 inches behind the eye-slit; 
blow holes above and a little anterior to eye slit. Length of 
flipper 7 inches, its anterior edge 12 inches behind the snout. 
Funis was attached to the belly about midway between the 
anterior and posterior end of the foetus. A low, but distinct dorsal 
ridge, the rudiment of a dorsal fin, commenced a little in front of 
a point midway between tip of snout and end of tail, and ex- 
tended backwards for between 10 and 11 inches along the middle 
line of back. It had a lighter greyish tint than the surrounding 
skin. Breadth of tail was 15J inches. In a profile view of the 
foetus a slight depression in the contour of the top of the head 
was seen in the region of the blow-holes. The foetus in utero 
differed therefore very materially in colour from such a half-grown 
specimen as Dr Fleming described*, in wdiich the upper part of 
the body was a dusky black, the belly white, and numerous oblong- 
spots extended horizontally along the sides ; still more did it 
differ from old specimens, which have a whitish marbled colour. 
The presence of a dorsal ridge is also of interest, as the Narwhal 
is described as without a dorsal fin. 
I availed myself of the opportunity of examining the dentition 
of the foetus. On May 20th, 1872, I described to the Society the 
* Memoirs Wernerian Socy., 1811. 
