164 Observation of the Ov'ujln of Varieties. 
details. Although an explanation of BRAUN-SCHIMPER'S 
series is. still wanting, each of the numbers in it (e. g., 
13, 21, etc.) may figure as a specific character; that is, 
it may be the constant mean for a particular species. On 
the other hand they may constitute stages of variation 
or characterize races whose nature is still unknown to 
us. We must therefore limit ourselves to a purely em- 
pirical description. 
It seems desirable to 
give a general outline of 
the significance of my ex- 
periment before I proceed 
to describe the details. 
The corn marigold is 
very common in cornfields 
over the greater part of 
Europe, as also its German 
names "Saatwucherblume" 
and "gelbc Kornbluinc" im- 
ply. It has thirteen ray 
florets in the inflorescence 
and fluctuates around this 
number according toQuE- 
Fig 29. Chrysanthemum scgctum TELET ' S law A commercial 
plenum. An almost completely 
double inflorescence. See also variety, called Chrysanthe- 
Plate II. 
mum segetum grandiflo- 
nun, whose origin is not known, is distinguished by the 
possession of larger and more numerous tongue florets. 1 
So far as my experience goes, bought seeds of this vari- 
ety give rise to a mixture of this and of ordinary C. 
segetum, no doubt on account of the fact that in the 
nurseries both are grown close together, for practical 
1 RUMPLER, Vilmorin's Blumengartnerei, 1896, II, p. 507. 
