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JOURNAL OF MAMMALOGY 
such they find their functional homologues in the procumbent lower 
incisors of the lemurs, the crenated lower incisors of Galeopithecus, and 
the specialized hair-scratching nails and claws seen in many mammals. 
The hair is raked through by this specialized hair comb, and then 
the comb is cleansed by the tongue and teeth. Not only is this 
toilet-use the obvious function of these digits, but it is the only func- 
tion that they possess, so far as I can learn after hours of watching at all 
times and seasons. 
Trichosurus is a skilled, but by no means a nimble climber. When 
alarmed it seeks to escape rather by remaining motionless than by the 
exhibition of any feat of exceptional activity. Its movements, as a 
rule, are slow and cautious, and great reliance is placed upon the 
grasp of the prehensile tip of the tail. It is rare to see the tail grip 
released until the creature is well satisfied that it has a firm hold 
by some other member. The foot with its highly specialized and 
nailless big toe is capable of taking a very firm hold, and descent is 
always made head downwards. The hands are always used for 
gathering food, and for holding it to the mouth when eating. 
Opossums are crepuscular feeders, eating directly they wake at dusk. 
Less than many other marsupials are they dependent upon the native 
Australian vegetation, for though they relish the pungent leaves of 
the eucalypti, they will eat almost any green leaves, and their great fond- 
ness for flowers is one of the reasons for their unpopularity. They 
drink but little and are quite independent of water when a plentiful 
supply of fresh green vegetation is to be had. When they do drink, 
they lap the fluid with great rapidity. Like wallabies and bandicoots 
they have the strange habit of licking their fur in very hot weather. 
The fore limbs especially are always kept wet when the animal is 
suffering from the extremely high summer temperatures. 
Of its means of keeping in touch with its environment its auditory 
sense and its tactile sense apparently take first place. Its sense of 
hearing is remarkably acute. The long ears are pricked and mobile 
when the animal is active, but are folded during repose. The tactile 
areas of the rhinarium and the naked pads of the hands and feet, as 
well as the numerous sensory vibrissae on face and limbs, are evidently 
of the highest functional importance. 
Vision, even during the time of the animal’s highest activity, does 
not appear to be at all keen, and seems to be of secondary importance 
only. I have had a fine male, three parts grown, in which there was 
complete double congenital cataract. This specimen came to grief 
