JONES — HABITS OF TRICHOSURUS VULPECULA 
189 
that an intimate acquaintence with the animal produces the im- 
pression that an inoffensive and stupid simplicity is the key note of 
its psychology. It is probably this simphcity which renders all 
opossums more or less tame, for there is very little difference in the 
degree of docility between a fresh caught adult and an animal which has 
been born and bred in captivity. A wild male has been in the habit of 
paying evening visits to my captive specimens, fearlessly coming into 
the outhouse in which their cages are placed. This visitor would 
permit me to approach and stroke it, but would not allow itself to 
be grasped or picked up. Freshly caught animals show practically no 
resentment of captivity, and when placed in a temporary cage are 
very reluctant to leave it for a larger and more comfortable one. 
When handled, even when chased and captured, they, like most 
marsupials, remain silent; they will bite and scratch, and defend them- 
selves stoutly, but as a rule they utter no cry. But though they are 
thus voiceless when molested by man, they are extremely noisy in 
their own domestic quarrels. The ordinary sound expressive of 
resentment, and a prelude to all encounters, is a long drawn inspiratory 
hiss. This hiss may die down as a harsh grunt, but when continued 
becomes increasingly high in pitch and may be modulated into a harsh 
cry, which rises to a raucous screech when the animals are fighting. 
During the breeding season, when fights are most common and the 
animals are most vocal, the male produces a curious sound like a 
sharp hcking of the lips and a cHck of the tongue. So far, I have not 
heard a female produce this sound. The cry of the young when re- 
moved from the mother is extremely loud and quite peculiar, and can 
be described best by saying that it is so like the voice of the common 
South Austrahan tree frog that it is almost impossible to distinguish 
it from the frog’s voice. 
In fighting among themselves the oppossums use the claws of the 
fore feet far more than the teeth, and although they often infiict 
scratches on each other and remove quantities of hair, even the 
noisiest encounters usually result in no great damage to the opponents. 
In performing the toilet of the fur, the palmar surfaces of the hands are 
licked, and the face is washed after the familiar manner of the cat. 
The fur of the rest of the body is combed with the syndactylous digits 
of the foot. The syndactyhsm of the digits is most certainly, in all 
the syndactylous marsupials that I have watched, a specialization of 
structure adapted to the toilet of the hair. The second and third 
pedal digits, with their parallel nails, constitute a hair comb, and as 
