CLASSIFICATIOX OF SEEDS 



263 



it easily to pierce the earth above. The root is at the 

 lower part of a short hypocotyl. 



As the corn has but one cotyledon, it belongs to the 

 class of plants known as monocotyledons (moii-o-kot-v-lr'- 

 don : Greek, mono, one ; kotyledon, socket). The bean, 

 having two cotyledons, belongs to the class dicotyledon* 

 (di-kot-y-leMon : Greek di, two ; kotyledon, socket). 



LABORATORY STUDY WITH CORN 



Remove most of the endosperm from a few kernels, and plant them. 

 How does the growth compare with that of a kernel retaining ;ill its 

 endosperm? Examine whole corn kernels, noting (1) silk sear on top ; 

 (2) depression on the side ; (3) hard outer covering; (4) stalk by which 

 it was attached. Cut crosswise a kernel which has been soaked in wal 

 and identify the embryo, scutellum, endosperm, and hard outer covering. 

 Split a kernel lengthwise and find the same parts. Remove the embryo 

 from another soaked kernel and study its attachment to the endosperm. 

 Look for the plumule and root. 



Examine such seeds as you can obtain and make a report, using the 

 following table as guide. 



Bean . 

 Pea . 



Corn . 

 Squash 

 Etc. . 



Size 



Embryo 



EASILY 



Seen 



IIili M AT 

 BlDH 



llll.t M OS 



End 



Two 



COTJ i.l - 

 DONS 



■ '■ B 

 COTYl K- 



|..,N 



202. Classification of Seeds. — The comparative stud\ oi 

 the bean and corn seeds shows the important parts of seeds 

 and explains the chief differences between them. The 

 common seeds are classified as follows : monocotyledons: 

 grass, wheat, barley, oats, and rye ; dicotyledons : Bquash, 

 morning glory, tomato, radish, and beet. 



