INTRODUCTION. XXI 



IY. MONOCHLAMYDE^E. 1 



Perianth single, or none. This Sub-class contains 

 Twelve British Orders, numbered from LXYIII. to 

 LXXXI. (Pp. 528577.) 



CLASS II. MONOCOTYLEDONS. 



Seeds with a single cotyledon (p. 570). It is sub- 

 divided into Two Sub-classes, PETALOIDE.E and GLU- 

 MACE^E. 



Sub-class I. PETALOIDE^E. 



Flowers with petals. This Sub-class contains Seven- 

 teen British orders, numbered from LXXXII. to 

 XCYIII. (P. 571 to the end.) 



Sub-class II. GLUMACE^I. 



Flowers formed of chaffy scales, or glumes. This 

 Sub-class contains the Grasses and Sedges. 



CLASS III. ACOTYLEDOSTES. 



Flowerless plants. Here are placed the Ferns, Mosses, 

 Liverworts, Lichens, Sea-weeds, and Fungi. 



Each of the Natural Orders, or Tribes, alluded to 

 above, consists of a number of plants which are more 

 or less like one another in various respects, especially in 

 the organs of fructification. The plants comprised in 

 each Tribe are again distributed into genera, or families, 

 each genus including all plants which resemble one 

 another yet more closely in the essential characters of 

 fructification. A species, or kind, is an assemblage of 

 individual plants agreeing with each other in all essen- 

 tial points ; and individuals which differ one from 



(1) From the Greek monos, one, and chlamys, a mantle or covering; the 

 plants of this Sub-class never having both calyx and corolla. 



