MONOOOTYLEDONES. 



451 



cate their real affinities. Unfortunately for us, howeverj. 

 none of our systematic manuals follow any of the Continen- 

 tal systems ; we are compelled, therefore, to use for the pres- 

 ent the prevailing form of the Candollean system. In this 

 book the sequence of the groups is the reverse of that in 

 most American and English books, in order to bring tlie ar- 

 rangement of Angiosperms into harmony with that of the 

 rest of the vegetable kingdom. 



Sub-Class I. Monocotyledones. 



[Endogenm of De Candolle.*) 



550. — ^In these plants the first leaves of the embryo are 



alternate, hence we say 

 that they have one cotyle- 

 don. The venation of the 

 leaves is for the most part 

 such that the veins run 

 more or less parallel to 

 one another, and when 

 they anastomose enclose 

 four-sided areolae ; rarely, 

 however, their veins are 

 irregularly distributed, 

 and they anastomose so as 

 to form an irregular net- 

 work. 



Fig. 381.— Longitudinal section of the seed 

 of Indian corn (Zea Mais), c, adheri-nt wall 

 of tlie ovary ; n, remains of the style :,fs, 

 base of the ovary ; all the remainder of the 

 figure is the true seed ; eg, ew, endosperm ; 

 Bi: — ss, cotyledon of embryo ; e, its epider- 

 mis ; A, plumule ; w (below), the main root ; 

 ■ws, the-root-sheath ; w (aliove), adventitious 

 roots springingfrom the first iuternode of the 

 stem. X 6.— After Sachs. 



lias its broad dorsal surface in contact 



Tlie germination of Monoco- 

 tyledons may be illustrated by 

 a couple of examples. In the 

 seed of the Indian corn the 

 embryo lies partly imbedded 

 in one side of the large endo- 

 sperm (Fig. 331). The first leaf 

 of the young plant (the cotyle- 

 don or scutellum, Fig. 331, »e ) 

 with the endosperm ; anteriorly 



* From the Greek Mov, within, and yheiv, to bring forth. The 

 name was given under the false impression that these plants were 

 " inside growers," and the Dicotyledons " outside growers." 



