GLIMPSES INTO PLANT STRUCTURE 51 



in Fio". 33, taken from a plant commonly found 

 on moorland hills and known as "club-moss." This 

 is a tiny moss-like plant only a few inches in 

 heioht at the present day ; but many o-eolo!_;-ical 



Fig. 34. The structure of a rush stem 



ages ai^'O the ancestors of our club-mosses were 

 amongst the most prominent forms of the vege- 

 table kingdom, bourweonino- as laroe trees with 

 stems or trunks sometimes four and five feet in 

 diameter. Fossilised trunks of these great club- 

 mosses are often found amono-st the coal measures; 



