(»7) 



a. Synoptic Collection. This is designed to illustrate the 

 plant world. A series of characteristic objects is installed 

 as a basis for illustrating each plant-family. These speci- 

 mens are accompanied as far as possible by plates, drawings 

 or photographs, while on the shelves are arranged additional 

 objects, such as flowers, fruits, woods, specimens of fossil 

 plants and models of various organs of plants, all intended 

 further to illustrate the structural characteristics of the dif- 

 ferent groups. This collection is arranged according to the 

 most natural and thus far most generally satisfactory inter- 

 pretation of the interrelation of the plant-families; it may 

 be considered as falling into two main series, namely, the 

 flowerless or spore-bearing plants and the flowering or seed- 

 bearing plants. 



The flowerless plants fall into three subkingdoms : ( I ) the 

 Thallophyta, in which the plant-body is not differentiated 

 into stems and leaves, represented by the slime-moulds, the 

 bacteria and other micro-organisms, the seaweeds, the fungi 

 and the lichens ; (2) the Bryophyta, represented by the mosses 

 and their immediate relatives; and (3) the Pteridophyta, 

 including the ferns and the fern-allies. 



The Thallophyta (cases 1 to 36) , may be defined as plants 

 without true roots, stems or leaves, but notwithstanding their 

 simple structure they exhibit an infinite variety of form and 

 color. 



The Myxomycetes or slime-moulds (case 1), standing at 

 the bottom of the plant scale, occupy the first exhibition case 

 placed at the right hand side of the stairway from the main 

 floor. They are thallophytes, having neither chlorophyl 

 nor (in their vegetative condition) a cell-wall. These very 

 simply constituted plants usually grow upon and derive their 

 nourishment from decaying organic substances. They vary 

 greatly in size, some being exceedingly minute, others assum- 

 ing the form of relatively large irregularly shaped masses 

 spreading in all directions as they grow. Most of the plants 

 are small, and the structure is very delicate, in fact some are 

 so fragile that a mere breath of air will ruin them. 



