102 Sudden Appearance and Constancy. 
and altogether better than any varieties then known; it 
was constant from the first and spread rapidly. 
I shall conclude this summary with a reference to the 
new species of Tomatoes which BAILEY has recently 
described. 1 He describes the origin of two new forms 
which he has called Upright and Mikado and which arose 
in his cultures. They differ from one another and from 
the parent species by more definite and more numerous 
characters than many among the older forms which are 
recognized as good species in the genus Lycopersicum. 
They arose suddenly as usual and were propagated by 
seed. 
The observations recorded in this and the two preced- 
ing sections, which are far from constituting complete 
lists, show that the origin of varieties and of elementary 
species both in the garden and in the field is amenable to 
experimental investigation, for the phenomenon is by no 
means so rare as is generally believed. The botanist 
will investigate the indifferent and useless forms with 
just the same result as the profitable ones, to which alone, 
of course, the practical man pays attention. The cultures 
need not be very extensive to afford novelties from time 
to time, though these must not be expected the first or 
every year. Once obtained, all that there is to be done 
is to isolate them as soon as they appear and pollinate 
them artificially. But it is far more important to go 
back to their ancestors, partly not to lose the historical 
evidence, but mainly in order to sow the seeds of these 
ancestors again and to find out if the novelty will be again 
produced, and if possible to discover the conditions which 
determine its appearance. Unfortunately there are many 
plants which do not lend themselves to such experiments, 
*L. H. BAILEY, Survival of the Unlike. 
