120 OBJECT LESSONS IN BOTANY. 
the circles of petals common in other flowers. Hence we 
have a class of Glume-plants and of Glumeless-plants, or, as 
the botanists say, Guomirer# and Peraurers. Thus we 
divide all the Flowering Plants into four Classes, viz.: 
1. Angzosperms ; Exogens bearing stigmas and seed-vessels. 
2. Gymnosperms ; Exogens with no stigmas, and with naked 
seeds, as the Pines, Firs, Larches, Cedars, Cypresses, Y ews, &c. 
3. Petalifere ; Endogens with no glumes and ordinary 
flowers. 
4. Glumifere ; 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 Dialypetale, or Polypetalous Exogens, having flow- 
ers with the petals distinct and separate, as in the Buttercup, 
Rose, Mustard. 
2. The Gamopetale, having flowers with the petals united 
into one piece, as in the Phlox, Morning-glory, Foxglove, 
8. The Apetale, having 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 (Cheno- 
podium). 
4. Next, the Gymnosperms are regarded as forming one 
cohort, called the Conoids, having the fruit usually in cones. 
(Less. XXIII.) 
258. After the classes, what is the next step in analysis? How are the 
Angiosperms subdivided? Please define the Polypetalous Exogens; the 
Gamopetalous; the Apetalous. What cohort do the Gymnosperms form? 
Why? What two cohorts do the Petaliferous Endogens form? Define the 
fifth cohort. Define the sixth cohort. What cohort do the Glumiferons 
Endogens constitute? 
