28 



Latent and Soni-Latcnt Characters. 



tions of descent and therefore of systematic relationship. 

 1 1 fuUy deserves and repays the attention given to it, as 

 Celakovvsky's a(hiiirable papers show. It is to be hoped 

 that others will, following the lines laid down by Hein- 

 RiciiER. imdertaKp the task of rendering these characters 

 more amenable to study by cultivation, and so bring an 

 increased number of them to light. 



The manifestations of latent characters are so rare 



that they scarcely ever lend 

 themselves to statistical study 

 (p. 19). When they recur 

 from time to time they are 

 seen to be extremely vari- 

 able, since as a rule even the 

 rarest anomalies are not 

 quite the same each time 

 they appear. It is easily seen 

 in such cases that the varia- 

 bility is a unilateral one; but 

 the construction of curves 

 usually fails owing to the 

 sparsity of the material. 



The half races are much 

 more favorable in this re- 

 spect. Here the deviations 



5 6 7 



Fig. T. Half Curves. A. Caltha 

 palnstris. Curve of the num- 

 ber of petals in 416 flowers. 

 B, IVeigelia amahilis, Curve 

 of the slips of the corolla in 

 1 145 flowers.^ 



are by no means so very rare. 

 As a rule the normal character still preponderates, but 

 material sufficient for statistical study can often be found 

 without difficulty. It shows clearly that the variation 

 is a unilateral one. The apex of the curve is the mean 

 of the normal character, and the deviations all lie on the 

 same side. And in ordinary cases they are less numerous 



^Ber. d. d. hot. Gcs., Vol. XTT. 1894, p. 197, Plate X. 



