154 CORRELATION OF COLOUR CHARACTERS IN RICE 
The chief situations of this colour are :— 
(1) The leaf-sheath, pulvinus of leaf, ligule and auricles. 
(2) The internode. 
(3) The small outer glumes. 
(4) Apiculus of the inner glumes. 
(5) The inner glumes as distinct from the apiculus. — 
(6) The stigma. 
The above will be readily understood by a reference to the plate. 
The varieties so far studied at Dacca with reference to the distribution of 
these colours may be broadly grouped as follows :— 
(1) Varieties with leaf-sheaths, apiculus of glumes and stigma coloured. 
(2) Leaf-sheaths and apiculus of glumes coloured, but stigma colourless 
(white). 
(3) Apiculus of glumes only coloured. 
Each of these groups may have colour in other parts also, such as the 
nodes, internodes, outer glumes and body of inner glumes as distinct from 
the small spot of colour at the apex, the so-called apiculus. Indeed the 
colour is found in so many combinations, each breeding true in pure-line 
cultures, that any satisfactory grouping is not possible. Types can only be 
described. Moreover, varieties which outwardly appear similar in colour 
characters may be found on investigation to have the colour situated in 
different parts of the cell-anatomy ; as, for example, in the internode and 
leaf-sheath, where varieties which outwardly appear the same may have the 
colour situated in the epidermal layer only, or in the bundle sheaths only, or 
in both together. 
Early results,! obtained chiefly from the analysis of the offspring of 
natural crosses, showed that these colours were frequently due to the 
interaction of several factors, and that they were often combined into 
patterns which were inherited as a whole. In order to investigate the 
mode of inheritance of these colour patterns more thoroughly, a series of 
crosses were made between a number of variously coloured paddies and 
green varieties, and the data discussed below have all been derived from 
the results of these experiments. In the first place, the inheritance of 
colour in each of the various situations referred to will be described without 
reference to the others. The combinations of the colour characters will be 
discussed later. 
1 Hector, G. P. “ Observations on the Inheritance of Anthocyan Pigment in Paddy 
Varieties.’ Mem, Dept, Agri. India, Bot. Ser., VIII, no. 2, Nov. 1916. 
