British Association . 
' [October, 
690 
The Sixth Report on the Conductivities of Coral Rocks, 
prepared by Prof. A. S. Herschell and Prof. G. A. Lebour, 
was read. The research and correspondence necessary to 
complete a historical sketch of the attempts hitherto made 
to determine experimentally the thermal conductivities of the 
terrestrial rocks most widely distributed, which the Com- 
mittee had proposed to draw up during the past year, were 
not so far advanced at present as to allow them to be com- 
prised in this year’s report. The Committee hopes, by 
continuing its inquiries for another year, with the addition 
to its number of Prof. W. E. Ayrton and Mr. J. Perry, of the 
Imperial College of Engineering in Japan, to carry out the 
object of their undertaking, so as to exhibit our existing 
knowledge of the date of thermal conductivity of those 
widespread kinds of rock which constitute the external ma- 
terials of the globe. 
The Fifteenth Report of the Committee for Exploring 
Kent’s Cavern, Devonshire, was read by Mr. W. Pengelly, 
F.R.S. He observed that this was probably the last report 
he should present on the subject, as the exploration work 
was fast drawing to a close. Work during the past year 
has been carried on in the “ High Chamber ” and its 
branches. This “ High Chamber ” contains only breccia, 
the oldest mechanical deposit in the cavern, and the crystal- 
line stalagmite which overlies it. Bones of bears and im- 
plements have been found in the breccia here, and also in 
that of the southern branch, called the “ Swallow Gallery.” 
Section D. 
The Biological Section was presided over by Professor 
St. George Mivart, F.R.S., who, in his Presidential Address, 
referred to the life and labours of Buffon, noticing his spe- 
culations concerning animal variation ; his belief in the 
direct effect of the surrounding circumstances on organisms ; 
and also his belief that new species have arisen by 
degradation. We may, Prof. Mivart thought, accept as true 
two propositions : — (1.) Animals may change in various 
ways, and amongst them, by degradation. (2.) Changes in 
the environment with isolation, induce and favour changes 
in form. He urged that inquiries should be pursued in two 
directions simultaneously, (a.) There might be undertaken 
one set of inquiries to investigate the effects on different 
species of the same variation of environment, (b.) Other 
inquiries might be undertaken with a view to ascertaining 
