126 BULLETIN: MUSEUM OF COMPARATIVE ZOOLOGY. 
Queensland coast with the Australian mainland. The proofs of the 
moderate subsidence given by Jack only intensify the separation, and 
furthermore this submergence was followed by an elevation, of which 
Jack says: “I hold that a great submergence of the eastern coast (as 
exemplified by Sydney harbor and the Townsville deep drifts) was at 
a comparatively recent date, succeeded by a movement of elevation 
which is still in progress." 
Steaming through Whitsunday Passage (Plate XXX.) we got our first 
fine view of the extensive denudation and erosion which has been going 
on since oretaceous times along the eastern coast of Australia. In the 
more southern colonies, New South Wales and Victoria, the peculiar val- 
leys of the Blue Mountains and the fine harbors which are found along the 
coast of the former give an excellent idea of the extent of this denudation. 
Moreton Island (Plate XXVI.), the Glassy Mountains, Breaksea Spit, 
and the passage between Frazer Island and the mainland (Plate 
XXVIL), are the most southern examples of the formation of islands, 
the former connection of which with the mainland is still clearly indi- 
cated. They are still partially connected, as it were, with the main- 
land, while to the north the islands, islets, and rocks, which undoubtedly 
once formed a part of the eastern shore, have become more widely 
separated. They are in a district in which the erosion and denudation 
have acted more powerfully. 
There is no proof of any extensive subsidence since the cretaceous 
period, but during that period there must have existed a comparatively 
deep sea separating that part of Australia which in a general way lies 
south of the area covered by the desert sandstone formation from the 
older lands to the north of the present Australian continent. The 
larger islands are generally nearer the continental shore; as we go 
out towards the edge of the Barrier Reef they fast become smaller, and 
near the outer edge of the reef we only find an occasional rocky islet to 
attest the former existence at from twenty to seventy-five miles from 
the present shore line of the outer and eastern edge of that continent. 
The farther east the more and the longer has the shore line been ex- 
posed to the disintegrating action of the sea. Thus the outer islands 
and islets first separated from the coast were reduced to the level of the 
sea long before the inner islands now forming the various archipelagos 
along the eastern coast of Queensland and within the Barrier Reef were 
separated from the mainland. On the flats thus formed, and on their 
outer edges, corals began to grow, and as the process of disintegration 
and erosion extended inland the corals followed in the same direction 
