AGASSIZ: THE GREAT BARRIER REEF OF AUSTRALIA. 131 
Great Barrier Reef by W. Saville Kent ;* and, finally, a number of refer- 
ences by travellers to the Great Barrier Reef, in which the authors either 
adopt or reject the theory of subsidence as explanatory of its formation, 
without however giving any new facts bearing upon the subject.? 
We need only discuss the views of Jukes and of Kent in the light 
of the observations made on the “Croydon” during my visit to the 
Great Barrier Reef. 
Jukes’s description of the “ First Bunker's Island,” in the northern part 
of the Capricorn group, remains to-day an excellent description of a 
pseudo atoll such as are common on the isolated reef flats of the Great 
Barrier Reef. Kent copies this as Jukes's description of Lady Elliot 
Islet.4 This certainly is a mistake, as the “ First Bunker's Island " is in 
the northern part of the Capricorn group, and “ twenty-five miles north- 
west of Lady Elliot Islet.” 5 
Jukes has, it is true, given a sketch of Lady Elliot Islet, but it 
has nothing to do with his description of “ First Bunker's Island.” 
On page 4 he mentions anchoring between * the third or northern 
Bunker’s Island” and “a large coral reef with a shallow lagoon and 
a small patch of dry sand on its western sido." This is probably 
Boult Reef. 
Kent, on p. 106, has copied Jukes's description of “One Tree Island " 
and of ** Heron” Island. Jukes was greatly puzzled regarding the mode 
of formation of hardened coral rock greatly weathered which forms what 
subsequent writers have called * beach rock " in coral areas. Jukes 
speaks of its surface as everywhere rough, honeycombed, and uneven, 
dipping toward the reef at an angle of 8° or 10?. Не has described 
this beach rock from Heron Island as well as from Wreck Island. 
Kent has also reproduced (p. 109) Jukes's account of one of the reefs 
belonging to the Swain group which Jukes explored, sailing about eighty 
miles north and south along the eastern edge, and ninety miles right 
through them in a west-southwest direction, passing through narrow 
channels from ten to thirty fathoms, the bottom being composed of 
angular grains of fragments of coral and shells.  Jukes was specially 
1 € The Great Barrier Reef of Australia, its Products and Potentialities." 
London, 1893. 
2 Such as: “Im Australischen Busch und an den Küsten des Korallenmecres,” 
von Richard Semon. Leipzig, 1896, pp. 278, 845. “Der grosse australische Wall- 
riff" von Albrecht Penck. Wien, 1896. 
3 Voyage of H. M. S. ^ Fly," Vol. I. p. 1. 
* 'The Great Barrier Reef of Australia, p. 101. 
5 Voyage of H. M. S. “Fly,” Vol. L. p. 819. 
