114 TRANSACTIONS OF THE [FEB. 11, 
filled with genuine creosote, but some preparation of crude well- 
oil. Can you enlighten me on this point? 
I hope you are not tiring with my notes about my pets, for 
believe me, the half has not been told of their winning ways. 
February 11, 1889. 
STATED MEETING. 
The President, Dr. NEWBERRY, in the chair. 
Fifty-five persons present. 
A communication was read from the Royal Bohemian Society 
of Sciences in Prague, announcing the death of the President of 
that body, Mr. Joseph Jirecek, on November 25th, 1888, in the 
sixty-fourth year of his age. 
The second lecture of the public illustrated course was then 
delivered by Professor ALPHEUS Hyartr, of Boston, upon 
MODES OF EVOLUTION IN FOSSIL SHELLS, 
with an extensive series of lantern views, showing the nature 
and variety of modifications in species and groups. 
The lecturer gave a few preliminary remarks on the meaning 
and general bearing of the doctrine of evolution, in which he 
held that this word is properly applicable to all kinds of varia- 
tion into new life-forms, as well retrogressive as progressive, 
and objected to the use of such terms as “avolution,” or the 
like, as proposed by some writers who would limit the idea of 
evolution to an implied advance. He followed these observa- 
tions by showing stereopticon figures of his series of shells of 
Planorbis collected at Steinheim, in Germany. These illustra- 
tions gave the audience, in a succession of views, the evolution 
of a number of distinct forms, which had arisen from four 
varieties of one species, Planorbis levis. This species was 
almost equilateral, the whorls revolving nearly in the same 
plane during their growth. One of the series evolving from 
this form gave rise to a large turbinated variety resembling 
what are usually called Trochiform shells. Other series were 
less changed, though showing a tendency to evolve into similar 
