54 
Journal of Agricultural Research 
Vol. II, No. i 
upon this pigment. This fact is of interest when taken in connection 
with the fact found in the other cowpeas above mentioned that it is 
intimately associated in these cells with a very large amount of melanin¬ 
like pigment. 1 In what way the intimate mixing of these two protects 
the anthocyanin from the rapid effect of reagents it is impossible to 
say, but it seems probable that some such interference is brought about. 
The melanin-like pigment is coarsely granular and orange brown in color. 
It is also to be observed that this pigment modifies the color tone tardily 
secured by the reactions of various reagents. Thus, with hydrochloric 
acid, the blue anthocyanin does not give a rose color, but rather a deep 
cherry red, probably due to the mixture of the usual rose tint with the 
orange yellow tint of the melanin-like pigment associated with it. The 
speckling, which is of the Taylor type, is due to anthocyanin contained 
in certain palisade cells. The basal-color layer has the usual pigment. 
The cowpea is the product of a cross of Red No. 4 upon Taylor No. 14, 
second generation. 
Another cowpea of a different color scheme needs mentioning, No. 
243-6-1. This one ranges from pale buff to strong red brown, speckled 
with black, on the New Era pattern. The palisade cells which repre¬ 
sent the ground color—that is, which are not connected with the speck¬ 
ling—are, as in the former case, of a dull brassy yellow. The same tint 
is found in the basal-color layer. From one-third to one-fifth of the 
palisade cells contain a deep-blue alkaline anthocyanin located in the 
lower end, and here again it was discovered that all the reactions normal 
to this pigment are greatly delayed, so that a longer period of time is 
needed to make the necessary tests. The melanin-like pigment is present 
in large quantity in all the palisade cells. This variety is the second 
generation of a cross of Red No. 4, crossed upon Whippoorwill No. 6. 2 
We come now to a cowpea which is probably wild. It is a Vigna 
sinensis (?), having the number 01653, and comes from Sokoto Province, 
Upper Nigeria, Africa. In some respects it is quite different from the 
cultivated cowpea. In matter of size it is from one-seventh to one- 
eighth the average size of cultivated varieties. Its markings are 
extremely interesting, in that they display on the same seed coat all of 
the features which are found to make up the color schemes of the culti¬ 
vated cowpeas, not only all the colors but all the styles of distribution. 
First, there is a basal color which ranges from pale clay or buff to reddish 
brown; second, this is extensively blotched or marbled with deep brown 
red, sometimes pretty well covering the seed coat; third, there is present 
a fine speckling of blue-black dots scattered over the seed coat; and 
1 This intimate mixing of blue anthocyanin with a deep-tinted melanin-like pigment and the consequent 
resistance of the former to reagents misled the writer at first into concluding that he here had to do with a 
black melanin-like substance; and in some remarks before the Washington Botanical Society on May 7, 
1912, the writer included such pigment with the others found in the cowpea. A report of this meeting, 
in Science, June 28, 1912, also contains this error, which is now corrected. 
2 Some individuals of this variety proved to have been contaminated by crossing; hence, the presence of 
Speckling in some of its descendants.—W. J. Spii4«man. 
