Apr. is, 1914 
Coloration of Seed Coat of Cowpeas 
49 
brown with an intensification of color about the hilum. A part of the 
palisade cells, perhaps two-thirds to four-fifths, contains a moderate 
quantity of the melanin-like pigment, the remaining cells being pigmented 
to only an extremely slight degree. The pigment is scattered throughout 
the cell cavity in a fine granular condition, instead of being massed in 
the lower end, as is usually the case. The basal-color layer ranges from 
a strong yellow to a decided copper or orange color, varying in this 
respect according to the general coloration of the seed coat itself. It 
has been impossible to learn the parentage of this well-known and widely 
cultivated variety. 
A cowpea strongly marked in what is known as the Whippoorwill 
pattern, made up from a basal color of a pale clay heavily marbled with 
a rich reddish brown, is No. 242-3-1. The palisade cells show the varia¬ 
tion in coloration that would be expected by the marbled character of 
the seed coat. The strongly pigmented cells of the marbled areas are a 
rich reddish brown, approaching to the color found in the basal-color 
layer. The other cells, making up the unmarbled areas, though not 
actually destitute of pigmentation, contain so minute a quantity as to 
only slightly affect the color of the basal layer beneath it. This latter 
layer is of an intense copper tint, the pigment being deposited in dense 
masses in the upper part of the layer. A very unequal distribution of the 
pigment in this layer corresponds somewhat but not accurately to the 
unequal distribution of the pigmentation in the overlying palisade layer. 
No trace of anthocyanin was found in any of the cells of this cowpea. 
Although the optical effect in the matter of color is not involved in the 
presence of tannin, it may be stated that this substance is more abundant 
than usual in this particular cowpea. Its parentage is Clay No. 17, 
crossed on Whippoorwill No. 6, second generation. 
No. 243-5-3 is a variety with monochrome seed coat ranging in color 
from a light to a very dark reddish brown. The cells of the palisade layer 
show a strong granular pigment of a light red, in some cases almost brick 
red, quite uniformly massed in the extreme lower end of these cells. In 
some instances the pigment is so finely divided that it is difficult to dis¬ 
cover it except when masses of cells are superimposed upon one another. 
Although the seed coat gives no indication of an unequal distribution of 
color, the sections seem to indicate that there is a slight excess of pigment 
in certain groups of cells over that in cells surrounding them. The basal- 
color layer has a much lighter tint than that found in the cowpea last 
mentioned. It is a lemon-yellow color, intensified in darker individuals 
to a decided brassy tone. The form of the palisade cells is normal. The 
parentage of this cowpea is a Red No. 4 crossed on a Whippoorwill No. 6, 
second generation. 
No. 242-5-2 has one of the two parents last mentioned and is similar in 
general color scheme, varying from buff to reddish brown. The palisade 
cells are abundantly supplied with a dull-yellow pigment, but quite vari- 
