13 PRACTICAL BOTANY. 



having their tips distinct or obsolete, the caljx is said to be 

 gamosepalous or monosepalous (one-sepalled). (PI. Y., 7.) 

 If, on the other hand, they are not in any way united into 

 one piece, the calyx is called 2?olysejpalous (many-sepalled.) 

 (PI. lY., 6.) 



If the Petals are united into one body in the same 

 manner, we call the corolla monopctaloxis (one-petalled) or 

 gamojpetalous (PI. YIII., 2) ; and if the flower has its pe- 

 tals distinct, the corolla is said to be polypetaloxis, (PI. 

 IV., 4.) 



41. The Pnji:NOOAMous Sekies divides into Ttoo 

 Classes. 



43. The First Class of the Phaenoganis (the class of 

 the higher grade) comprises the Plants with wood in a 

 zone^ or circle^ or in concentric annual rings (PI. II., 29) 

 around a central p>ith ; nettedr^eined leaves^ parts of the 

 floxoer mostly in fives or fours, and a dicotyledonoxis 

 {two-leaved) emlryo. This is the Class of the Exogenoxis 

 or Dicotyledonous plants, which we briefly call Exogens. 



43. The Second Class of the Phcenogams comprises 

 those plants, which have their icood disposed in separate 

 threads, scattered throxtgh the diameter of the stem, not in 

 a circle (PI. II., 28); the fioral parts ttsxially in threes, 

 never in fives ; the leaves nearly always longitudinally 

 veined; and a monocotyledonoxts {one-leaved) embryo. 

 This is the class of the endogenous or monocotyledonous 

 plants, which we briefly call Endogens. 



44. The CLASS EXOGE]S"S is divided into two sxch- 

 classes — the Angiosjyerms and the Gymnosperms. 



43. The Gymnosperms are characterized by having 

 their ovules (and seeds) naked — that is, not hidden in a 



