80 



ACADEMIC BOTANY. 



primitive types — Gymnogens and Endogens — live longest ; 



a character resulting, doubtless, from the needs of their 



former geological 

 conditions. 



162. Monocarpic 

 Plant s. — Perennials, 

 after a few years' 

 growth , usually bear 

 flowers and fruit an- 

 nually until they die 

 of old age. Among 

 Endogens, however, 

 and especially in the 

 Amaryllis Order, we 

 find Monocarpic, or 

 Once-fruiting plants. 

 The giant Fourcroya 

 of South America is 

 an example. The stem 

 is 400 years attaining 

 its full growth, a height 

 of 60 feet. Then it sud- 

 denly sends up a 

 branching flower-stalk 



Fig. 98. — Plaue-tiee, or Sycamore {PUUanm orienlutu). 



(panicle), which in 6 weeks reaches a height of 40 feet, with correspond- 

 ing dimensions, and bearing 20,000 lilies. 

 In a few weeks more the fruit ripens, and 

 then the whole plant dies. The Agave 

 (Pig. 115) is also monocarpic. It is called 

 Century Plant for this reason ; but the 

 plants bloom at the age of 20, 40, or 50 

 years. 



163. Trees, as to form, are 

 Drooping, with branches (and sometimes 



trunks) declined: Weeping Willow, Birch ; 

 Fastigiate, with small, erect branches, par- 

 allel to the trunk ; Lomhardy Poplar ; 

 Round-headed, with solvent trunks and 

 nearly equal branches : Plane (Fig. 98) ; 

 Spire-topped, with exourrent trunks and 

 tapering branches : Pines (Pig. 97). 



164. Stems, as to habit, are 



Ascending, Assurgent, when they rise ob- 

 liquely, as in Polygala (Pig. 185) ; Caespi- 

 tose, when in turfy patches like the Mosses ; 

 Declined, bent on one side : Judas-Tree ; 



Decumbent, at base erect, but the stem ,J^°-i!!Cv™T?J7„&r 

 __ . . '.,-, ... T> 1. T^-j- i«wn nigrum) plant entire: 6, 



prostrate Without rooting : Easpberry ; /)i/- ft. cut open • c, flower. 

 fuse, loosely spreading : Raspberry ; Pro- 

 cumbent, Prostrate, Trailing, lying flat on the ground without 



