SI'ERMATOPHYTES : ANGIOSPERJIS 



217 



cotyledons, and the seed coat containing the cotyledons 

 remains like a lateral appendage npon the straightened axis. 



It is also to be observed in 

 many cases that the young root 

 system, after gripping the soil, 

 contracts, drawing the yonng 

 plant deeper into the ground. 



118. Summary from Angio- 

 sperms. — At the beginning of this 

 chapter (§ 107) the characters of 

 the Gymnosperms were summar- 

 ized which distinguished them 

 from Angiosperrns, whose con- 

 trasting characters may be stated 

 as follows : 



(1) The microspore (pollen- 

 grain), chiefly by insect pollina- 

 tion, is brought into contact with 

 the stigma, which is a receptive 

 region on the surface of the car- 

 pel, and there develops the pollen- 

 tube, which penetrates the style 

 to reach the ovary cavity which 

 contains the ovules (megasporan- 

 gia). The impossibility of con- 

 tact between pollen and ovule im- 

 plies inclosed ovules and hence 

 seeds, and therefore the name 

 " Angiosperm. " 



(2) The female gametophyte 

 is but slightly developed before 

 fertilization, the egg appearing 

 very early. 



(3) The female gametophyte produces no archegonia 

 but a single naked egg. 



Pig. 194. Seedling of hazel ( Car- 

 plnus), showing primary root 

 {hw) bearing rootlets {$w) 

 upon which are numerous 

 root hairs (r), hypocolyl ihj, 

 cotyledons (c), yonng stem 

 (e), and first (/) and second 

 (I') true leaves.— After Schim- 



PER. 



