The Meeting of the British Association at York. 181 
Professor Calkins followed with an account of the continuation 
of his former work on the life-history of Paramoecium in which 
he showed that cultures of that organism periodically pass 
through a crisis in which their power of division is lost, but that in 
the absence of conjugation with members of another brood, 
they can he restored to vigour by treatment with various solutions 
such as extract of meat, brain extract, phosphates, etc. At length, 
however, there comes a time when no treatment is able to revive 
the flagging energies of the organisms and they die. Professor 
Calkins concluded that generally the stimulus of fertilization is 
necessary to revive the protoplasm worn out by numerous divisions. 
Mr. Doncaster gave an account of the behaviour of the polar 
bodies in parthenogenetic eggs, but the behaviour of these structures 
is so different in different forms, and the accounts are often so 
contradictory that very little evidence can be obtained from them 
as to the nature of fertilization. 
Professor Poulton pointed out that he had used the term syngawy 
(invented by Professor Hartog and used by Mr. Blackman in his 
Paper) in another sense, to refer to individuals which would breed 
together. He also suggested that the artificial conditions under 
which Paramoecium was living might involidate the conclusion of 
Professor Calkins that conjugation was absolutely necessary sooner 
or later in the life-cycle of these organisms. 
Professor Hartog claimed that he had priority in the use of the 
term syngamy , and suggested an alternative word to be used in 
Professor Poulton’s sense. He compared the phenomena known in 
the orange, Funkia, etc., where cells of the nucellar tissue grow into 
the cavity of the embryo-sac, and under the stimulus of the 
exceptional nutrition, grow into embryos exactly like normal ones, 
with Professor Calkins’ results. 
Dr. Rosenberg described a very interesting case of partheno¬ 
genesis among plants in which the two nuclei formed by the first 
division of the embryo-sac-mother-cell later fused together and so 
started a generation with the double number of chromosomes. 
This case is almost exactly parallel with that of the parthenogenetic 
eggs of Artemia among animals. 
Professor Johannsen spoke of the relation of “ pure race ” 
breeding to Mendelian heredity, and questioned the validity of the 
evidence for graft hybrids. 
Professor Hickson stated that he had failed to find in recent 
work any further evidence for the belief—now accepted as a dogma 
