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mal. Both on the upper and under parts of the body the hairs are 
of a deep slate-grey colour next the skin; those on the belly are of 
a dirty yellow colour. On the back, the hairs are most of them 
brownish, or yellowish brown near the point, and black at the 
point. The ears are covered both externally and internally with 
fine short hairs. The hind-feet have five toes; the fore-feet also 
have five toes, but the inner one is very small and has a very short 
nail; the other toes have long, compressed and powerful nails. 
The hairs of the moustaches are of a dusky colour. 
The discovery of the Rodent above described is due to Mr. T. 
Bridges, whose notes relating to it are as follows :—‘*‘ This species 
of Rodent is very common on the eastern side of the Andes, where 
it completely undermines the face of the country, especially in dry 
places, making it very disagreeable for the rider, as the horses are 
continually plunging into the burrows. It must lay up a winter 
store, or otherwise migrate, or remain buried in the snow at least 
three months during the winter season. The specimen is a female.” 
