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specimen, broken up into fragments ; vertebre little interrupted 
as a series, bat each individual segment broken. into minute 
fragments which made it impossible to remove them whole. One 
wing was nearly complete, but the bones of the other were only 
in fragments ; caudal vertebrz in fair condition. The legs of all 
the birds found were directed downward, and were in a flexed 
position. The lower end of the tibio-tarsus, the tarso-metatarsal 
and toe bones were invariably incrusted with hard limestone to. 
the thickness of half an inch, which had to be chipped off, and in 
the course of removal of this crust some bones were injured. The 
lower ends of the legs extended to a depth of several feet under 
ground where water was always present. The third bird skeleton 
was rather incomplete :—head in fragments; pelvis imperfect ; 
no sternum; the legs only were in good condition. The remains 
of these three birds were found within a space of about six square 
yards and, as they lay on one side, their heads and necks were 
directed towards the south-west—the deepest part of the lake bed. 
‘It may be mentioned that all the bones situated near the surface 
were always found broken up into innumerable fragments, which 
was due to the growth of tufts of fibrous crystals. 
[We are indebted to Mr. E. F. Turner, Demonstrator of 
Chemistry at the University, for the following note on the con- 
stitution and formation of these crystals: ——The material sub- 
mitted consists of clay impregnated, and covered, with filiform 
crystals, which are composed of halite, together with smaller 
quantities of gypsum, glauberite and alunite. On saturating 
the mass of clay with water, and then allowing it to dry, 
the crystals again appeared on the surface—capillary attraction 
leading the saturated solution of the above salts to deposit, in the 
first place, the cubical crystals of common salt and the octahedral 
crystals of alunite; these then become bound together by the 
prismatic crystals of glauberite and gypsum, the result being that 
a protruding mass of filiform crystals is formed. | 
‘Under atmospheric influences, in which dry conditions of the 
clay are succeeded by moist, these crystals are alternately formed, 
in and around the bones, and redissolved ; with the result that 
constant scaling takes place from their surfaces until at last the 
whole bone crumbles into fine powder. Or, short of this, the 
infiltration of the bones with so much salt confers on them such 
hygrometric properties that, even in an ordinary damp atmo- 
sphere, they become moist, and can only be dried with great 
difficulty ; while, on the other hand, in the very dry weather of 
the Australian summer they become brittle to an extreme degree. 
The shrinkage, on drying, and consequent cracking of the masses 
of clay, enveloping the bones, also constituted a cause of damage. 
To give some idea of the extent to which this took place it may 
