6 o 
Sedimentary Formations 
Several collections of New Guinea rocks have been sent to ine; 
but although it was asserted strenously that gold was found in 
them in the district visited by H.M.S. “Basilisk,” I have not 
been able to recognise the existence of any auriferous matrix, 
though it is well-known that alluvial gold was discovered during the 
visit of H.M.8. 44 Rattlesnake ” on the coast at the other side of 
the Island. I find, however, that nodules of excellent haematite 
occur at New Harbour about 100 feet above the sea. AVo may 
hope for satisfactory additions to our knowledge of that great 
Island from the results of the Expedition so nobly undertaken 
by Mr. Macleay. 
In 1870 I added a remark or two about the discovery of a 
living Ceratodus in the waters of Queensland in the preceding 
year; the only previously known existence of the genus being 
the teeth found in Triassic European rocks to which that name 
was given. 
This was an interesting addition to the living Tngonia, the 
Cestracion, the Terebratula, &c., of Australia, which connect the 
present period with the forms of life once held to be extinct. 
Inquiries respecting this curious fish have resulted in the dis¬ 
covery of other species than that fi rst found (Ceratodus Forsteri) 
and what is more extraordinary, fosilized teeth, of which I was 
shown examples by Professor YVyville Thomson who found them 
in an excursion purposely undertaken in search of the fish during 
the stay of 1I.M.S. 41 Challenger” in Port Jackson. 
Since the first description of the fish by Mr. Krcfft, Dr. 
Gunther, F.E.S., has published a valuable 44 Description of Cera¬ 
todus, a genus of Ganoid Fishes recently discovered in rivers of 
Queensland, Australia” in the Phil. Transactions (part II. 187 L). 
The result is that both Agassiz aud Pander had from teeth found in 
the Lias and Trias of Europe come to conclusions which the living 
Ceratodus fully justifies. Dr. Oldham also had reported Cerato¬ 
dus teeth from' Maledi, south of Nagpur, in India. Australia 
in this instance precedes India. The fish turns out to bo allied 
to Lepidosiren, and its habits are amphibian, feeding on grasses 
and weeds in fresh water. 
Dr. Gunther goes into a most elaborate and minute examina¬ 
tion of the anatomy of all parts of the fish and a comparison 
with other fishes of the same and dilFereut types. He sums up 
thus : — “ The Dipnous type is represented in the Devonian and 
Carboniferous epochs by several genera ( Pipterus , Gheirodus , 
Conchodus . Fhaneropleuron ), it is then lost down to the Trias and 
Lias, where the scanty remains ofa distinct genus, Ceratodus , testify 
to its presence ; no further trace of it has been found until the 
present period, where it re-appears in three genera, one of which is 
identical with that of the Mesozoic era. Now, at present, scarcely 
any zoologist will deny that there must have been a continuity 
