344 JOURNAL OF SCIENCE. 
the ceratodus. He went up to the Burnett River in April, and 
found that at that time the fish were ripe, the ovaries and testes 
being nearly developed ; but it was not till the beginning of 
September that he found the first eggs of the ceratodus. It was 
his belief that the fish had been in the water the whole time, 
but the extent of the waterhole and the habits of the fish made 
the difficulty very great in securing it. He spent many weeks 
hunting, and, with the assistance of the blacks, turned up many 
hundred waterholes before he found it. The eggs were laid upon 
the weeds. They were laid singly, resembling those of the com- 
mon newt. The whole development of the ceratodus had a 
strange resemblance to that of the amphibians, and anyone who 
had any acquaintance with the development of the newt would 
at once perceive the resemblance. It seemed that the fish would 
only drop their eggs on a particular weed. These eggs were 
fertilised in the water in a similar way to some species of the 
newt. The eggs he found it very difficult to get. They were 
covered with an enormous quantity of gelatinous matter which 
required some special means, such as a scissors, to remove. He 
was eight days before he got a single egg out whole. When he 
succeeded in getting the early stages, it remained to rear them 
until they were practically identical with the adult fish. This 
was a very difficult task, as the enemies of the ceratodus were 
very numerous. There were two kinds of fungi which attacked 
the eggs. He putin crustacea to devour the fungus, but these 
in turn attacked the young fish when it emerged from the egg. 
He was three months, till near the end of November, developing 
the eggs. The fish were now living—had been hatched some 
weeks ago. The hind legs of the ceratodi were not yet developed. 
The development of the fins would probably yield important 
knowledge on embryology. The egg of the ceratodus was 
similar to that of the kangaroo. He then proceeded to describe 
the monotremata, namely—the ornithorhynchus and echidna. 
These, though differing from one another, were identical in 
structure, and were in every way similar animals. They were 
the representatives of large series of forms which once existed in 
other parts of the world. These two living representatives 
formed something quite as unique in its way as the ceratodus. 
They were both milk-giving, and both suckled their young. 
When he came out he had a strong belief that the ornithorhyn- 
chus and echidna produced their young in much the same way 
as the marsupials, and he thought last year he had confirmatory 
proof of this being so; but he found he was inerror. He thought 
he found in the pouch of the ornithorhynchus a cellular mem- 
brane ; but he found it to be only part of a ruptured egg. He 
then, with the aid of diagrams, described the stages in the de- 
velopment of the platypus. He had found that invariably the 
female platypus had two eggs, and these left the parent at the 
age of about a chick, thirty-six hours after the laying of the egg. 
With regard to the echidna, he had not determined the exact age 
at which the young were born. That of the platypus he had dis- 
