400 Proceedings of Royal Society of Edinburgh. [sess. 
as in the grilse, and the caudal fin still carries several spots. The 
adipose fin is, like the dorsum of the fish, a dark steel colour. The 
fork in the tail fin is well marked. Measurements taken with the 
caudal fin unextended, as in the photograph, show that the lower 
lobe of the fin extends 2 5 cm. beyond the central part of the fin. 
The length of the head is contained 4 T 6 T in the total length. 
The maxillary hone shows a condition midway between that notice- 
able in the parr or smolt and that of the grilse or salmon. In the 
parr the posterior margin of the bone reaches to a point vertically 
below the centre of the eye. In the adult fish the maxillary bone 
is prolonged backwards to a point vertically below the posterior 
margin of the eyeball, or beyond the eye altogether. In the 
Galway fish the point at which the maxillary bone ends is 
vertically below the posterior margin of the pupil of the eye. 
This and the arrangement of the opercular bones will be seen from 
the accompanying outline drawing of the head. 
{Issued separately February 1 , 1905 .) 
