The Significance of the Atavisfs. 



521 



vists, 1 the nine plants with cyhndrical stems and shght 

 broadening at the top; whilst 2-20 denote the breadth 

 of the stems in centimeters. 



The curve is seen to have two peaks, one of which is 

 formed by the atavists (a), the other by the fasciations 

 of mean breadth, i. e., of about nine centimeters. Ex- 

 pressed in words, the result is that transitions between 



9 10 11 12 13 14 15 16 17 18 19 20 



Cm. 



Fig. ii8. Crepis biennis fasciata. A curve representing the 

 breadth of the main stems of all the individuals of my 

 culture of 1895. The numbers under the base line indi- 

 cate the breadth of the stems in centimeters, o, stem 

 round; i, stems only flattened at the upper end; 2-20, 

 stems flattened along their whole length. The height of 

 the ordinates gives the number of individuals. Total 

 number of individuals 150. a, the peak of the atavists; 

 h, that of the fasciated individuals.^ 



the fasciated individuals and the atavists do occur, but are 

 relatively rare. The race produces by preference the 

 two pure types, and the same thing is seen to happen in 

 chance fasciations and in many other monstrosities. I 

 call to mind the relative rarity of hemi-tncotyls and hemi- 

 syncotyls, both in the wild state and in the tricotylous 

 'Bull. Scientif., he. cit., Vol. XXVII, p. 397. 



