MULTIPLE ALLELOMORPHS AND LIMITING 

 FACTORS IN INHERITANCE IN THE STOCK 

 (MATTHIOLA IN CAN A). 



By EDITH R. SAUNDERS, 



Lecturer, late Fellow, Newnham College, Cambridge. 



(With Plates VII and VIII and 3 Text-figures.) 

 CONTENTS. 



PAGE 



Introdaction . 149 



Summary of Earlier Results ...... 154 



Description of Biotypes 164 



I. Hoary 165 



II. Glabrous 167 



Evidence from further Crossbreeding .... 163 



Summary of Later Besults ...... 166 



Discussion of tVie Significance of the Results . . 169 



Experimental Data ....... 174 



Explanation of Plates VII and VIII .... 178 



Introduction. 



Two forms of the Garden Stock are commonly recogniged and are 

 familiar to every horticulturist. In respect of the one external charac- 

 ter in which they differ, viz. hair-production, they show the extreme 

 limit of range in either direction. At the topmost level stands the 

 type exhibiting a maximum degree of hoariness in all aerial green 

 structures and a sprinkling of hairs even on the petals : at zero point 

 the so-called wallflower-leaved or glabrous variety, which in its extreme 

 form lacks even a single hair. Almost unknown however is the inter- 

 esting and rare intermediate described in the earlier accounts as half- 

 hoary^ This latter plant was originally obtained, together with the 



^ Reports to the. Evolution Committee, Roy. Sac. Report I, p. 33, 190'2, ;ind Journal of 

 Genetics, Vol. v. No. 3, p. 145, 1916. 



