Nov., 1928 
The Queensland Naturalist. 
89 
counted 100 layers of strata to the inch. The material 
was as line as a sheet of paper. Those layers must have 
been laid down under some very favourable conditions 
in the earth’s history, and there must be miles of that 
class of country. What those conditions were was a 
problem the geologist wanted to solve. He would 
say that in all probability the silver-lead deposits 
of the Black Star lode went down to interminable 
depths. Whether there was a change in their mineral 
structure was, of course, another matter. Tie depicted, 
by means of the slides, a section of country bearing pre- 
CambriaA rocks between Templeton and Mount Isa, 
where, he said, there were five miles of strata that must 
have been in existence before our world (stratigraphieally 
speaking) began, before anything we recognised in the 
way of life began. It represented a world they knew 
nothing about, because no forms of life that might have 
existed in that period had been preserved, so far as they 
knew. Reference was also made by Mr. Dunstan to the 
suitability of the Mount Isa lodes for geophysical research, 
because of their being interbedded with other rock masses 
so different from them in physical characters and electri- 
cal properties. In the tracing of the lodes along the sur- 
face geophysics would be particularly useful as the exten- 
sion of the outcrops away from the main centre were 
marked by superficial coverings. 
At the conclusion of the lecture a vote of thanks 
was moved by Dr. E. 0. Marks, seconded by Mr. Heber A. 
Longman, and carried by acclamation. 
SPECIAL MEETING, 7th SEPTEMBER, 1928.— Mr. 
D. A. Herbert presided. Mr. T. C. Roughley, Economic- 
zoologist of the Teclmologieal Museum, Sydney, delivered 
a lecture on — 
THE LIFE HISTORY, CULTIVATION, AND PESTS 
OF THE AUSTRALIAN OYSTER. 
The lecture was attended also by members of the ' 
Yacht Club, and by many oyster growers and others 
i interested in the industry commercially. 
_ The story of an oyster’s birth and the aimless wan- 
derings of its childhood days was not only one of very 
great interest from a scientific standpoint, but a know- 
ledge of it was also of very great value to the cidturist, 
said Mr. Roughley. Until very recently the Australian 
rock oyster was regarded as being stable in regard to sex ; 
in other words, it was born either a male or a female, and 
