102 STUDIES IN INDIAN TOBACCOS. 



remainder could be classified as follows : — base slightly undulate, 

 slightly imdulate all over, undulate at the base only, undulate 

 all over, very undulate all over, a little less undulate than Type 

 9, — showing that in all probability the undulation of the base 

 is determined by a different factor to that of the general surface 

 of the leaf. The numbers obtained indicate the existence of two 

 factors and a ratio of 15 : 1, namely, 17+3 plants like Type 9 in 250 

 plants gives a ratio 11.5 : 1. It is, however, possible that the 

 occasional undulation noticed at the base of Type 51 owes its 

 existence to a third factor and that the plants that were even 

 more undulate than Type 9 represent the combination of the 

 factors involved in Type 9 plus this factor. The ratio 247 : 3 

 makes this appear possible. The seventeen plants like Type 9 

 would consist of the homozygotic combination Type 9, the 

 heterozygotic intermediate between Type 9 and Type 9 intensi- 

 fied by the factor from Type 51. In a three factor combination 

 the ratio of these to the total number of plants would be 3 : 64, 

 i.e., there should be twelve plants, not seventeen. The number 

 of plants examined is, however, two few to enable any definite 

 conclusion to be drawn. 



The "frilling" of the edge appears to be inherited indepen- 

 dently of the surface undulations. This character cannot 

 be observed when the general undulations of the leaf are great. 

 In the present case this character was observed on fifty-seven 

 plants. Of these, fifteen had no frilling at the edge, the others 

 were frilled to a varying degree. This gives a ratio 42 : 15, or 

 2.8 : 1, so that here we are dealing with a simple factor. Some 

 of these plants with flat leaves and frilled margins were 

 carried on in the Fg generation, and the following results were 

 obtained : — 



Culture 694 — 105 plants, 78 with frilled margins, 27 with flat 

 margins. 



Culture 167—99 plants, 73 with frilled magrins, 26 with flat 

 margins. 



