42 Transactions British Mycological Society. 
it grew and Bernard considered it probable that it acts similarly 
in orchid tissues and increases the degree of concentration of 
the sap. This problem of autonomous germination recalls to 
mind that of parthenogenesis—the development of an ovum 
without the intervention of a spermatozoon. The egg possesses 
all the substances necessary for activation: the spermatozoon 
is an inciting cause of these reactions within the egg system on 
which development depends. Parthenogencsis occurs naturally 
in certain groups, but it has been brought about experimentally 
in numerous cases where fertilization normally obtains*, f. 
Apparently the first successful attempt was made by Tichomiroff 
in 1886, who stimulated the unfertilized ova of the silk moth 
to development by rubbing them between two pieces of cloth. 
Various methods have since been used such as treatment with 
fatty acids, certain salts such as barium chloride, lipoid solvents 
such as chloroform, hypertonic and hypotonic solutions, etc.f. 
Another significant similarity is that artificially activated eggs 
always show a marked slowness in their rate of development, 
even with the best methods, as compared with the fertilized 
eggs. This suggests, according to Lillie, some factor that has 
not yet been successfully imitated in any artificial way. Is it 
possible that in both cases accessory food factors (vitamines) 
may play a part? In considering the case of seeds it might be 
pointed out that there are many instances of peculiar germina 
tion known in other phyla. Pinoy§ showed that spores of 
Myxomycetes such as Chondrioderma difforme do not germinate 
unless bacteria are present. Ferguson|| discovered that the only 
way in which she could germinate the spores of the common 
mushroom effectively was by having a little mycelium of the 
fungus present in the cultures, and Servettaz | found that a 
species of Oospora activated the growth of the moss Phascum 
* F. R. Lillie, Problems of Fertilization. Univ. of Chicago Science Series 
(1919). 
t Y. Delage and M. Goldsmith, La ‘parthénogénése naturelle et expéri- 
mentale. Paris (1903). 
¢t The only case in which parthenogenesis has been induced in the entire 
vertebrate phylum is in the frog, where Bataillon in 1910, after years of vain 
attempts, finally succeeded by the exceedingly simple method of pricking the 
eggs with a fine needle. It is necessary that blood or tissue extract should be 
carried into the egg by the needle. This method has been abundantly con- 
firmed and tadpoles so obtained have been reared to maturity by Loeb and 
Bancroft. 
§ E. Pinoy, Role de bactéries dans le développement de certains Myxo- 
mycétes. Ann. Inst. Pasteur, xxI, p. 632 (1907). 
|| M. C. Ferguson, A preliminary study of the germination of the spores of 
Agaricus campestvis and other Basidiomycetous fungi. U.S. Dept. Agric, 
Bureau of Plant Industry, Bull. No. 16 (1902). 
"| C. Servettaz, Recherches expérimentales sur le développement et la 
nutrition des mousses en milieux stérilisés. Ann. Sci. Nat. 9 sér. XvII, pp. I1I- 
224 (1913). 
