42 
Journal of Agricultural Research 
VjI. II, No. i 
writer has not been able to discover the parentage of this variety. The 
reasons for its white color are two: First, the palisade cells are practi¬ 
cally destitute of contents. Such residuary amount of cytoplasm as is 
present occupies a very minute part in the cell cavity and generally 
its upper third, instead of being in the lower end, as is usually the case. 
Parallel with this fact the usual spindle-shaped tapering of the cell 
cavity is here so slight that the diameter of the lower part is hardly 
greater than that of the upper part. In other words, the fine hairlike 
extension of the cell cavity upward does not exist. Near the upper 
part of the cell the somewhat narrow canal cavity widens out, and it 
is at this point that the small residue of cytoplasm is to be found. The 
cells are also more loosely bound together than usual, so that intercellular 
spaces between them are quite frequent. The second reason for the 
white color is that in the basal-color layer, which in most cowpeas is 
colored with a dense yellow or orange-buff pigment, there is no trace 
of pigment present nor any pigment reaction obtainable. The seed 
coat is, as a whole, much thinner and weaker than in other varieties, 
and its permeability to external moisture should therefore be greater. 
As already stated, several other cowpeas approximate this true albino 
in being practically colorless, but certain individuals of these varieties 
show a slight trace of pigmentation in the basal-color layer. These 
varieties, 212-2-11, 212-6-8, 213-2-4, and 214-3-2!^, have the striking 
irregularity in form of the palisade cells and the lack of taper in the 
cell cavity just described in the case of No. 0632. Special mention 
should also be made of a somewhat analogous case in No. 239-5-3-18. 
This is also a cream-colored cowpea, but has a deep purplish pigmenta¬ 
tion around the hilum, forming an “eye/* In view of this localized 
pigmentation it is necessary to classify this variety under Division 
IV, the palisade cells in the area of the “eye” having both anthocyanin 
and melanin-like pigment. The color scheme of this portion of the seed 
coat will therefore be treated under Division IV, but as the structure 
of the uncolored seed coat, exclusive of the “eye,” shows certain curious 
features identical with the white forms just described the case is here 
given for comparison. A transverse section of the cream-white seed 
coat of this cowpea shows remarkable contortion in all its layers. The 
palisade cells have very strongly marked the abnormal shape previously 
mentioned, having heavy walls and being shorter than usual; their form 
is irregular and twisted upon its axis. The cell cavity is very broad at 
the base, narrows suddenly at its middle, and again broadens slightly 
at the upper end. The very small residue of cytoplasm is generally 
found located in this upper widened portion, thus corresponding to the 
albino, No. 0632. Here also there is no appreciable trace of pigment 
to be found in the palisade cells. The cells of the remaining layers of 
the seed coat are also much contorted and have, in general, heavier 
walls than normally. A minute amount of pigment is present in the 
