A GENETICO-PHYSIOLOGICÂL STUDY ON THE FORMATION ETC. 
75 
Thus we see that the pigment yielding mechanism in the seed coat of 
different species of plant falls in general under a similar category, particularly 
in the seed coat of the legumes. 
4. Discussion. 
To a gene we imply a specific protoplasmic entity which sets up the 
biochemical apparatus in the sporophytic cells and to the end product of the 
reaction performed by the mechanism so set up, we refer a character, morpho¬ 
logical and physiological. Therefore, even we infer a gene to a character, that 
gene itself may have no direct relation to the character. A catalyst does 
not appear in the final product of a chemical reaction, but may alter the 
velocity of the reaction and sometimes change the position of equilibrium to 
be attained. 
When such agencies or genes are paired forming an allelomorph, and 
they segregate in a normal way, we can deduce the relation between the 
character and the gene by the numerical ratio of character that is required 
by the supposed genetic entities. We disregard the biochemical processes 
involved in the changes which are set up by the gene to bring about the 
equilibriin, of which state we perceive the character. Dynamically viewed, 
however, the possibility is not excluded even in such a case in which a 
single allelomorphic character-difference is due to more than a factor-difference. 
Supposing the change A->0 in which the substance A undergoes certain 
changes to form the substance 0 which may be regarded as a single character 
in the Mendelian sense, such as a purple pigment in a certain organ in the 
plant. A ->0 reaction would appear to be a single change when the initial 
and the end product alone is considered, but it may involve the catenary 
changes A—>Z>— » G—>D 0. Such complex changes are likely to occur in 
most of the biochemical processes like respiration and photosynthesis which 
seem comparatively simple when the initial substance and the final product 
alone lire considered. 
If we consider an imaginary instance in which A-*B, B ->• C, C-+D, and 
D ->0 reactions are involved in a whole change A-*0, and these separate 
changes are governed by the respective genetic entities, yet they are not 
