SUMMARY OF SEEDLINGS 111 
Summary of Seedlings. — Seedlings of Flowering Plants are 
either monocotyledonous or dicotyledonous on the basis of the 
number of cotyledons. Among the Monocotyledons the tem- 
porary root system is a prominent feature, and the cotyledon may 
remain in the ground as in the Grasses or be raised to the light as 
in the Onion. In Dicotyledons the first root system is usually 
the permanent one and may consist mainly of a tap-root or of 
many roots nearly equal in size. In many Dicotyledons the coty- 
ledons are raised to the light where they function to some extent 
like ordinary leaves. The fleshy ones, however, lose their stored 
food in a short time and fall from the plant. In some cases, as 
the seedlings of Buckwheat, Morning Glory, and Cotton illustrate, 
the cotyledons become more leaf-like and persist longer, although 
they are always easily distinguished from true leaves. In some 
Dicotyledons the cotyledons remain in the soil and the plumule is 
raised to the light by the elongation of the stem of the epicotyl. 
