THE GEELONG NATURALIST. 25 
house. The Black Cockatoo (Calyptorhynchus funereus) is very 
plentiful in the ranges at times. They feed on the grubs from 
the rotten wood. These birds generally fly in small mobs of six or 
seven. They have a strong smell something like rotten seaweed. 
November 25th.—I find the Olivaceous Thickhead (Pachycep- 
hala olivacea) breeds in the ranges this month. We secured three 
birds—two females and one male. We did not see the nest but it 
appears to be close at hand. The Rufus-headed Bristlebird 
(Sphenura BroadbentiN breeds here. I got a nest with young 
birds while cutting scrub in a gully. They had scarcely any 
feathers, but could run about like young partridges. Pardalotes 
plentiful. I dissected the Spotted Pardalote (Pardalotus punctatus) 
and proved that those with white spots on the head are males, and 
those with yellow spots females. In the striped-headed variety 
Pardalotus striatus) those with red feathers on the wing are 
females. The Blue-spotted Painted Lady (Pyrameis Kershaw) 
appears at Bambra in the early part of September, also the Admiral 
(Pyrameis Itea). In October the Junonia and the Agaristae 
appear as also the Pieris Teutonia. The Pieris Harpalyce and 
Pieris Aganippe appear in November. 
November 26th—The butterflies that were so plentiful a month 
ago arenearly all gone. There are a few spotted winged Agaristae 
and a good many white winged, with an odd Painted Lady. 
OUR SILURIAN ROCKS. 
By H. BEILBY. 
To an uneducated person it seems incomprehensible that the earth 
could ever have had an appearance much different from its present 
one. Science, however, shows that by continued cooling, gases 
‘become liquid, liquids solidify, and solids contract and grow denser. 
Laplace's theory of creation is now, I believe, generally accepted 
by scientific men. This theory is that the particles of all creation 
were originally in a gaseous state, and that with the lapse of time 
they cooled and approached one another, forming huge highly- 
heated masses. With the revolution of each mass rings were 
thrown off, which, of course, retained their rotatory motion; and as 
a rule the rings broke up and the fragments still revolving threw 
off rings in the same way. In this manner the sun and planets 
were formed. Heat is not of hell; geologists know nothing of such 
places, whatever the future may bring forth. E 
