THE WILD ORCHID 



tubers. Fig. %2 (Plate 57) will, however, explain 

 matters. Above the flattened and divided tubers 

 are some strong, vermiform roots which direct 

 their gi-owth towards the earth's centre, and con- 

 sequently exert a downward pull at the base of the 

 stem. One result is that every 3^ear the tubers get 

 deeper into the earth ; therefore, the older the 

 plant the greater will be the difficulty of removing 

 it uninjured. The tubers spread out somewhat 

 laterally and are divided into finger-like segments. 

 Now this arrangement places the orchids amongst 

 the most up-to-date of plants, so to speak, as 

 regards their roots. These slender roots penetrate 

 the soil deeply and thus sink the tubers into the 

 earth well below the frost level, and so their rich 

 food stores are protected from cold and above- 

 ground enemies. Also the stem above the tubers 

 is weak, and is readily broken at that part, so that 

 a pull from above only results in breaking off the 

 upper part of the plant, a loss which the roots 

 and rich tubers will remedy in the course of 

 time. 



The tubers themselves are of peculiar interest. 

 As is common with thrifty and advanced plants 

 that suddenly make a bold show of bloom, the 

 flowering spike of this wild orchis is produced at 

 the expense of a previous season's growth. A 

 frirther glance at Fig. %2 (Plate 57) will show that 

 both the tubers of the same plant appear to be 

 about the same size ; and this arises from the fact 

 that both plants were gathered midway in the grow- 

 ing season. Early in the year we should have found 

 J 129 



