

\ \\\ \<\. . >1 I 111. 



looser structure of the hilum. Tl.U can easily be demonstrated 

 by plains beans in water, \\lu-n the spread of the water from the 



ion of tin- mirrop>le \\ill be indicated l.y the swelling and 

 urinkliiiK of the integument Fig. 83, - After a time the 

 entire integument becomes quit.- soft .ind water i- readily drawn 

 through it owing to the f.i. t ili.it the storage foods in the embryo 

 are in d tttad \\ith it and draw the water through by 



osmo-i-. r.nvhilh removing the integumenl from a soaked bean 



I IG. 83. I-'ruit and M-ed of the bean: .1, mature fruit or pod: s, style; 

 C, remain- "t i-.il>\: 0, "vary. At left tin \><\ ha- been i>|iciu-d, showing four 

 i.ichcd t<J the walls of the ovary by funiculus. B, two views of a 

 -n i| /;, hilum <>r war marking attachnu-nt <>f funirulus to seed; m, micropyle. 

 < ", uriiiklin. 1 < -Mt i au-<-d by the entrance of water through the micro- 



j.ylc and hilum. /'. <-mlir\<> "t M-rd after removal of integument c, coty- 

 l.-dmi-. At riv;hi IMU- !' tin , Mtylcd<>n-> ha- I'.-cii n -nniM <! to -how the plumule, 



. and tlu- hyp'x-.ityl. ''.v. /.', halt" <>f the meinl MMIK m- integument. 



\\c nntc that the nnl>r\i> i-- \\i-ll dr\ i'l( iprd, consisting of two 

 ll, -h\ . ot\ Irdons and a shorl stem I l ; ig. 83, D, E). The plumule 

 i- \\.-ll dc\flo])cd, l.rarine; t\\o lc,i\f>, and the short hypocotyl 

 and root a rr rmli>-<-d in a sheath fnnncd from the integument. 

 Note that the hypocotyl and rool an- ^ituatrd in-ar the micropyle. 

 Hn\\ does thi- arran^i incni \\ork to the advantage of the em- 

 brv . ' \llo\v the M-ed in germinate and it will be noted that the 

 ali-orpti'in "| water firsl < aii-e^ the einlir> o to expand and rupture 

 the integument . This is immediately followed by the growth and 

 l..n-aii'>n "t' i lie lo\\er jiart of the h\ pocotx 1 whirh results in the 

 jui-hine; out of the n.ot \-'ig. 84, .1). Thus it happens that the 

 \i-r\ |>ait of the embryo that shows the first signs of growth is in 



