LITE HISTORY OB MOXOTIJF.MES, 



230 



"Puff-Pug" i- found in the breeding burrows only, so far as 1 have 

 observed, and not in tbe shorter resting burrows of the adults. There are 

 usually three lots of pug in a tunnel, which are usually placed where there are 

 turns, but always close to a pug-pit. Some burrows contain only two pugs, while 

 others have four. The pugs may be six to twelve inches thick, though this mea- 

 surement is very indefinite owing to the variability of the burrows and their fit- 

 tings. Further, all the nests I have examined have been imbedded in this pug, and 

 one which I investigated particularly had three inches of pug below it in the nest- 

 cavity. 



The platypus evidently removes the pugs as she leaves or enters the nests. 1 

 have taken a female from a newly-made and complete nest which was pugged m 

 three separate places. Similarly other females which were each nursing a young one in 

 their nests were tightly pugged in. while the burrows leading to several nests in 

 which 1 found s,ts of twins and triplets without their mothers, were likewise 



plugged up. 



The constant removal and working of the soil of which the pugs are built 

 makes it so sofl and line that it sometimes becomes quite velvety to the touch, and 

 clings like Hour if squeezed in the hand. It is always slightly damp alter being 

 worked up by the platypus, but in the nest containing triplets without their 

 mother, the pug near the nest had dried and shrunken away from the sides of the 

 tunnel so much that 1 was able to move it in a mass, though it fell to powder in 

 ray hands when slightly squeezed. It gave me the impression that the mother 

 must bave been quite a considerable period away from the nest. 



The hair on the tail of the female platypus is inclined to be dishevelled at all 

 times, and there is frequently a bald patch on the upper surface. I have seen 

 several specimens, including two during the 1919 season, in which the hair was 

 worn away from an area about an inch in diameter, situated about one and a-half 

 inches from the tip id' the tail. 1 Suggesl thai this is due to friction or heat re- 

 sulting from the coiled-up position of the animal when she is sitting on her rump 

 on the damp and decaying vegetation of the nest, when she is either hatching her 

 eggs or nursing her young in their earlier stages. 



Again, it is possible that the females make use of the tail when constructing 

 the pugs which block up their breeding burrows. These pugs might be made 

 either with the animal's paws or with the head rather than with the tail. In the 

 former case, however, one would expert to find impressions of the knuckles on the 

 face of the pug — tbe web of the hands being always protected when the platypus 

 is walking, climbing, or burrowing by being tucked away in the palm; but I have 

 failed to find any such imprints. If, on the other band, the head is used, it 

 would seem that the sensitive membrane of the bill must come into unpleasant 

 contact with the hard earth forming the bottom of the tunnel, while the eyes and 

 nostrils would be subject to irritation arising from the fine loose pug-earth. 



The tail may also serve to clear the earth from the tunnel when the platypus 

 is digging the burrow. The female certainly scratches away tbe soil with her 

 front paws, and throws it under her body, and it is then perhaps pressed away 

 behind her with a flick of her trowel-like tail. It may be that she scratches ahead 

 for some distance, and then brushes or flicks the earth behind her as she backs out 

 of the tunnel. The tail can be readily bent or coiled into such a position as is 

 necessary to carry out this operation, particularly that portion of it which would 

 be required if it be so used. It would appear that the female must utilise the 

 tail in some such manner, since she could scarcely turn within the burrow, which 

 is only of about the same dimensions as her own body, and she rarely makes a 



