120 OBJECT LESSONS IN BOTANY. 



tBe circles of petals common in other flowers. Hence we 

 have a class of Glume-plants and of Glumeless-plants, or, as 

 the botanists say, Glumifee^ and Petalifer^. Thus we? 

 divide all the Flowering Plants into four Classes, viz. : 



1. Angiospernis ; Exogehs bearing stigmas and seed-vessels. 



2. Gymnosjperms / Exogens with no stigmas, and with naked 

 seeds, as the Pines, Firs, Larches, Cedars, Cypresses, Yews, &c. 



3. Petaliferw ; Endogens with no glumes and ordinary 

 flowers. 



4. Glumiferm; Endogens with glumes instead of petals, as 

 the Grasses, Sedges, Grains. 



258. Again, each of these Classes are to be subdivided into 

 Cohorts, as follows : the Angiosperms are divided (not very 

 naturally) into three cohorts, viz. : 



1. The Dialypetalw, or Polypetalous Exogens, having flow- 

 ers with the petals distinct and separate, as in the Buttercup, 

 Rose, Mustard. 



2. The Gamopetalm, having flowers with the petals united 

 into one piece, as in the Phlox, Morning-glory, Foxglove. 



3. The A2)etalcB, 'hnving flowers without petals, either 

 naked, or with only one circle of floral envelopes (which must 

 then be considered as sepals, whatever be the color) ; as Gin- 

 ger-root (Asarum), Poke {Phytolacca), and Pig-weed {G/ieno- 

 podium). 



4. Next, the Gymnosperfns are regarded as forming one 

 cohort, called the Conoids, having the fruit usually in cones. 

 (Less. XXIII.) 



258. After tlie classes, what is the next step' in analysis 1 How are thp 

 Angiosperms subdivided 1 Please define the Polypetalous Exogens; the 

 Qamopetalous ; the Apetalous. What cohort do the Gymnosperms form 1 

 Why ? What two cohorts do the Petaliferous Endogens form 1 Define the 

 fifth cohort. Define the sixth cohort. What cohort do the Glumiferous 

 Endogens constitute? 



