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Newman.—Notes on the Physiology and Anatomy of the Tuatara. 225 
food. They sleep much and very soundly, requiring to be much disturbed 
or pulled about ere they slowly waken. They are timid, much frightened 
by noises, and will run into their holes or to the nearest shelter or crouch 
motionless at sight of a man. They are very fond of water, liking to lie 
full length in it during great part of the day. One of mine laid several 
eggs in the water. They fight viciously, and bite hard. A skeleton in the 
Museum shows an old fracture of the mandible, with some displacement 
and callus, the result of a fight. Tuataras will live for months without 
eating, and then suddenly eat heartily every day. 
Tuataras, like young crocodiles, will not eat flies or other insects that 
are still, or meat lying at the bottom of the cage; but if the flies or beetles 
run about or the meat is moved they will quickly seize it. Like young ` 
crocodiles too, they will not bite when caught. When eating, their jaws are 
moved straight up, no rotatory motion existing. Tuataras are perfectly 
silent. When caught between a man’s fingers, their ribs being tightly 
squeezed, they utter sounds which are really groans, and even these sounds 
are uttered only when in great pain. When washed with soap and water 
the skin colours become very bright and distinct. 
Tuataras lay their eggs in holes in the sand when wild, but when captive 
on the bare earth or in the water in their troughs. Like the common 
English lizards ( Lacerta viridis) they lay eight or ten eggs at a time; they 
are about two-thirds of an inch in length, covered with a thick material 
containing a variable amount of lime. None of the eggs laid in eaptivity 
have yet been hatched. Mr. Burton told me that four tuataras laid eleven 
eggs in one night, but one of mine laid hers at intervals of several days. 
Mr. Darwin, in his learned and fascinating work on “Sexual Selection,” 
describes the arts and graces and appearances whereby male lizards woo 
their mates. The male tuataras have no special strongly-marked tints, no 
special personal attractions ; and, unlike the males of several other species 
of lizards, are not much, if at all, bigger than the females. The absence 
of special sexual attributes is due perhaps to the fact that the tuatara, 
unlike other lizards, has no penis, therefore probably small sexual passions, 
and but little rivalry. The males are so like the females that they have not 
yet been distinguished with certainty. Dr. Günther, noticing the presence 
of a crest of dorsal spines and of long, slender, acute-pointed claws, 
thought that tuataras did not burrow. Tuataras not only infest the holes 
dug by the mutton-bird, but burrow others for themselves. 
They burrow in the loose sand and pebbles on the banks of rivers or on 
islets. Captive tuataras are constantly burrowing; they dig the claws of 
their fore-paws into the soil, sometimes using the right and left paws 
alternately, at others using one for a long while; they fling = soil far 
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