11. SYNCOTYLOUS RACES. 



§ 9. HEMI-SYNCOTYLY, SYNCOTYLY, AMPHI-SYNCOTYLY. 



Alongside seedlings with split or double cotyledons 

 there occur others, the seed-leaves of which have fused 

 so as to form one single organ. They are, however, much 

 rarer, but not so rare that they cannot be found every 

 vear, at least in some sowing or other. Tricotyls may 

 be found in the proportion say, of one in a thousand, 

 but syncotyls, as a rule, only one in tens of thousands 

 of seedlings. 



In the sowings of 1895 which we have already men- 

 tioned (p. 380), I found, amongst more than 250,000 

 seedlings of 40 species, only 10 syncotyls as against 150 

 tricotyls. Where they occur more abundantly this is due 

 to inheritance, for as soon as the syncotyls are allowed 

 to flower in isolation and their seeds are saved separately, 

 it is found that they inherit their character in almost the 

 same degree as do tricotyls. 



Instances of syncotyls were afforded me by Aster 

 fcncUus, Clarkia clegans, C. pidchella, Cerinthe gym- 

 nandva, Chrysanthcinuin Myconis, Hclichrysuin hractca- 

 fujji, Phacdia tanacetifoUa, Silene hirsiifa, AnagaUis gran- 

 diflora, EpUohhmi hirsuUim, Hesperis matronalis, Pent- 

 stciunn gentianoides, Rohinia Pseud- Acacia, and many 

 other forms -} but always in small proportions. A few 



* Further instances are given by H. B. Gruppy, Irregularity of 

 Soiiu^ Cotyledons, Science Gossip, N. S., Vol. II, 1895, p. 171. 



