362 



TricctMlo^'is Races. 



a seedling of Acer Pseudo-Platanus with four seed-leaves 

 which I found in the spring of 1887 in a forest and trans- 

 planted to my garden. Here it developed its stem. As 

 soon as this had definitely split, and just before the cotyl- 

 edons were about to fall away 

 I dried this specimen in order 

 to keep and photograph it. 



It is obvious that such twins 

 do not belong to the tricotyl- 

 ous race, that is to say, that 

 their anomaly is due to some 

 other elementarv character. 

 Therefore they should not be 

 counted when recording the 

 seedlings, nor be used as seed- 

 parents. But as their nature 

 can only be determined for cer- 

 tain in some cases, it is not al- 

 ways possible to take this pre- 

 caution ; and the fact that the 

 hereditary values obtained from 

 tetracotylous individuals are 

 sometimes worse than those 

 from the corresponding trico- 

 tyls may in part be due to this 

 circumstance. 



For the rest tetracotyls do 

 not in any essential respect be- 

 have differently in inheritance 

 from the tricotyls. From their 

 seeds are produced, besides the atavists, mainly tricotyls, 

 with hemi-tricotyls and tetracotyls in the usual dimin- 

 ishing proportions. My tricotylous half race of Scvopliu- 



Fig. 72. Amarantus specio- 

 sus. Forking of a stem 

 of a tetracotylous plant 

 with two leaves in the 

 fork which have grown 

 together dorsally. The 

 figure shows also their 

 axillary twigs. 



