Ot 
G. P. HECTOR 15! 
COLOUR IN THE LEAF-SHEATH. 
The development of colour varies greatly. It is generally developed 
mainly in the epidermis and underlying layers of the inside of the leaf-sheath, 
in the epidermis and adjacent layers of the outside of the leaf-sheath, in the 
tissues surrounding the bundles (bundle-sheaths), and may also occur scattered 
in the general parenchyma. Frequently, on the outside of the leaf-sheath it 
is found only in the epidermal layer towards the margin, thus producing the 
conspicuous red line seen in some varieties running down the overlapping 
edge of the sheath. These different colour situations may be due to different 
factors, but in our experiments, coloured leai-sheath means simply the 
presence of colour of any sort visible from the outside to the naked eye. This 
colour in the leaf-sheath has always been found dominant to its absence, and 
to segregate in F, in asimple 3: lratio,a9: Tratio, a27: 37 ratio, and ima 
15: 1 ratio. Thus the colour is due either to a simple factor or to two or 
more interacting factors. 
The table gives details of crosses in which these various ratios have been 
obtained — 
Theoretical Variety 1 Observed ratio 
ratio | Colour X no colour Colour : nocolour Colour : no colour 
Total 5. families l 
Se! Pankhiraj x Pookhi 3:2 1 
1,015 : 317 J 
One family 
| Surjamukhi'- x Pookhi i t 2°8 ees 
Tei 6 261 
( Total 4 families } 
| Muramagar x Pookhi f 2°6 : 1 
| 2,198 : 818 
| Total 9 families 
Matichak ™ Pookhi ; } 3°2 1 
DIO: 829 
Total 7 families 
Bailabakri > Pookhi , 2°8 : 1 
1 $485 : 1,202 
9: 7 Total 4 families 
Redics 1) t Agartollah x C 25 1:3 | 
aa |! 2670 : 1999 J) 
Total 2 families 
liga c9 x C25 { ; 1 1-06 
Ts, 644: 686 
Total 3 families 
ane | Noachur x Pookii |) 16) 2550 
1,129 : 70 
EB 20 ee 
