LEGUMES FOR SEED 243 



of late maturing varieties, no pods may be formed. The per cent, 

 of shelled peas to pods or unshelled peas may vary from about 

 50 to 85. The pods may be brown, purple or blackish, though 

 light yellow is the prevailing color. They vary somewhat in 

 diameter, and in length from 5 to 10 or more inches. The shape 

 of pods and shape of seeds are to some extent related, and give 

 rise to two types with many gradations between : 



(1) A rounded form so closely packed in the pod that the sides of the 

 pea are flattened or indented, giving the pod a tightly stuffed, corrugated, 

 plethoric appearance. This class of pea is known as Crowder. 



(2) A flattened form, kidney-shaped, and placed farther apart in the pod, 

 which is smoother and leaner in appearance. The pods of Cro^vders are gen- 

 erally quite stubby and short; those of the Kidney type are long. 1 



The color of the seed is extremely variable, consisting of 

 solid or mottled shades of white, yellow, green, pink, purple, 

 red, brown, and black. A ring around the scar is common, giv- 

 ing rise to names of varieties, such as "black-eyed" or "purple- 

 eyed." There is also a great variation in the time required to 

 ripen seed, which may vary from two to seven months. Early 

 planting, excess of moisture and of nitrogen will prolong the 

 period of growth in the same variety. There is a somewhat 

 constant relation between the period of growth and the habit 

 of growth. Early maturing varieties are dwarf or bushy and 

 usually produce seed, while those with trailing habit are later in 

 maturing and produce greater abundance of vines, but usually 

 produce no mature seed north of the South Central states. 



300. Variations Due to Environment. It is commonly held 

 that the habit of growth of different varieties of cowpea varies 

 greatly with the climatic conditions. It is said that erect bush 

 varieties become trailers when taken southward, when sown 

 unusually early or upon very wet soil ; while trailers assume the 

 bush habit when taken northward or planted quite thickly. 



1 Georgia Sta. Bui. No. 26 (1894), p. 171. 



