131 1 T 



Hi 



ANALYTICAL KEY. lxvii 



Flowers all male * . . 132 



lowers all female 140 



[ale perianth of 3 to 5 divisions 133 



*" \ Male perianth of 6 divisions , 139 



-|oo f Stamens as many as the divisions of the perianth 134 



1 Stamens indefinite 138 



{Male flowers in globular heads in a terminal raceme. Females ax- 

 illary, joined two together in a large prickly burr, with incurved 

 points Bueweed Gen. (p. 456.) 

 Flowers, male and female, distinct, or in heads, not prickly . . .135 



- oc , J* Male perianth of 4 parts 136 



[ Male perianth of 5 or 3 parts Gooseeoot Fam. (p. 690.) 



{Leaves all radical, linear and fleshy, or transparent. Marsh or water 

 plants 137 

 Stems leafy. Leaves flat Nettle Fam. (p. 741.) 



pMale flowers one or two on a stalk, with very long stamens. Females 



sessile Littorel Gen. (p. 685.) 



Male and female flowers minute, mixed together in a small terminal 



L head Eriocaulon Gen. (p. 883.) 



-o 8 J Leaves opposite, simple Mercury Gen. (p. 736.) 



\ Leaves alternate, pinnate Poteritjm Gen. (p. 259.) 



^Leaves alternate, with sheathing stipules. Stamens 6. Nut enclosed 



in the calyx Dock Gen. (p. 706.) 



Leaves small and fine, in tufts. Stamens 6. Fruit a berry. 



Asparagus Gen. (p. 849.) 

 139 <j Leaves small and heath-like. Stamens 3. Fruit a berry. 



Crowberry Gen. (p. 738.) 

 I Leaves radical, long, arrow-shaped. Stamens and carpels numerous. 



L Aquatic plant Arrowhead Gen. (p. 794.) 



'"Perianth 2- or 4-cleft. Stigma sessile, tufted. Leaves opposite, 



stinging i Nettle Gen. (p. 742.) 



Perianth 3-cleft. Styles 2, simple. Leaves opposite, not stinging. 



Mercury Gen. (p. 736.) 

 Perianth 6-cleft, the 3 inner segments larger. Styles 3, with short 

 fringed stigmas. Leaves alternate or radical . Dock Gen. (p. 706.) 



3. Trees or Shrubs. 

 1 ... /Leaves opposite 142 



\ Leaves alternate or in tufts 145 



-tAoJ Leaves divided, lobed or angular, deciduous 143 



\ Leaves entire, evergreen 144 



{Leaves lobed or angular. Stamens about 8. Fruit with 2 diverging 

 wings Maple Gen. (p. 175.) 

 Leaves pinnate. Stamens in pairs, collected in clusters. Fruit with 

 one erect wing . . Ash Gen. (p. 554.) 



{Parasitical shrub with green dichotomous stems. Fruit a berry. 

 Mistletoe Gen. (p. 375.) 

 Erect branching shrub with shining leaves. Fruit a few-seeded capsule. 

 Box Gen. (p. 737.) 

 f Male flowers in catkins, separated by scales only. Females solitary 

 145 •< or in clusters, or in catkins, usually different from the males . . 146 

 [ Flowers hermaphrodite or diclinous, each with a distinct perianth . 147 



{Leaves entire and mostly evergreen, needle-like, or narrow or scale- 

 like. Anthers sessile on the catkin-scales . . Pine Fam. (p. 770.) 

 Leaves flat, mostly toothed. Stamens distinct from the scales. 

 Catkin Fam, (p. 747.) 



140 



