INHERITANCE— IMPROVEMENT BY BREEDING 191 

 red colour by shutting out the light, so that it is difficult to CHAP. 



tell whether the K, silks which are selfed are full red, or only 

 red-haired. 



147. Red Cob-colour. — Experiments conducted by the writer 

 (and it appears, simultaneously by East and Hayes (1)), show 

 that red cob-colour is dominant to white cob-colour, and behaves 

 as a simple monohybrid. These authors suggest that " it is not 

 beyond probability " that dihybrid reds may be found in an 

 extensive series of crosses. Cob-colour is not necessarily 

 coupled with red endosperm colour, for red cob-colour is not 

 infrequently found in a white-grained breed, e.g. Hickory King, 

 which normally produces white cobs. Many yellow-grained 

 breeds have red cobs, but white-cobbed ears are often found 

 amongst them ; other yellow-grained breeds normally have 

 white cobs, but red-cobbed ears are occasionally found amongst 

 them. East and Hayes record a case in which perfect coup- 

 ling occurred between red cobs and red pericarp colour. 



148. Glume Colour. — The glumes often carry red colour, 

 and vary considerably in the amount of redness present ; some- 

 times it is confined to very narrow or broader streaks along the 

 nerves. Glume colour appears to be correlated with colour in 

 other parts of the plant, for East and Hayes state that they 

 have not yet found a plant which has red glumes and yet 

 shows no red colour in other parts of the plant, though one 

 has been found that is pure for red glumes and yet shows no 

 red in other parts with the exception of the silks. 



149. Development of u Pods". — Pod maize (Fig. 51) when 

 crossed with breeds free from pods, behaves as a simple Men- 

 delian monohybrid. The podded character is dominant, and 

 appears in the F., generation in the proportion of 3 to 1 ; the 

 extracted recessives breed absolutely true (East and Hayes, 1). 



150. Inheritance of Ligule and Auricles. — Emerson (1) 

 finds that absence of ligule and auricle behaves as a recessive 

 to presence of these organs, and that they are transmitted as a 

 single hereditary character. Four liguleless plants, crossed 

 with unrelated normal-leaved plants, produced 103 Fj individ- 

 uals, all with normal leaves. Twelve of the latter were selfed, 

 and produced 748 F 2 plants, of which 572 had normal leaves 

 and 176 had no ligules, or practically a 3 : 1 ratio. Counting 

 together all families in which both types of leaf occurred, he 



v. 



