46 
Transactions of the Society. 
hairs constituting the under-coat. In the living animal, and in 
freshly captured specimens, the long hairs have a greenish hue, 
which has been observed to fade in the process of drying and 
preserving the felt. This greenish tint is due to the presence of 
large colonies of minute algae growing on the stout, long hairs. 
Under the microscope these hairs are seen to possess elongated 
scales which lie singly, overlapping the hair-shaft (elongate type 
of imbricate scale), and it is in the crevices of these scales that the 
minute algae find lodgment. The long hairs average about 
of an inch in diameter, and have a well-marked continuous medulla 
about three youths of an inch in diameter. 
The unicellular algae which form colonies between the scales of 
the hair-shaft are probably closely allied to Protococcus viridis 
( Pleurococcus vulgaris), and are bright green in colour ; the largest 
cells averaging 20*00^ an inch in diameter, and having a large, 
more or less central nucleus. Bipartition takes place by the 
formation of a partition wall, which cuts the cell in halves. This 
is the predominant type of alga, but, in addition, colonies of a 
smaller form, averaging in the largest cells y^^th of an inch in 
diameter, are present in isolated patches, scattered at intervals 
among the scales of the hair-shaft. It is the presence in lesser 
numbers of these pink colonies that serves to partially mask the 
bright green of the larger forms, giving to the hair, as seen by the 
naked eye, a dull greyish-green hue. 
