178 Pkscott, Reproduction of Terrestrial Orchids, [vj'^xxxiv 



paired tubers are, of course, present. In Caladenia they are 

 often readily observable, but in Glossodia they are not so easily 

 discovered. These are really hot cHmate orchids, and Nature 

 has therefore provided their tubers with special protection 

 against heat and evaporation. On casual inspection, the plants 

 of Glossodia major invariably have apparently only one tuber 

 each. On dissection, the paired tubers (old and new) are 

 found to be enveloped in quite a number of tough fibrous 

 sheaths, often as many as twenty of these sheaths being found 

 enfolding the tubers, the inner ones being of a silky nature, 

 the outer ones being very tough. There is no doubt that these 

 sheaths are for protective purposes. 



The juvenile tuber is developed inside the sheath. Later, 

 a second leaf appears fi^om the parent plant, then two flower- 

 stems appear to be coming from the one tuber. The tuber 

 increases in size until a separation occurs. Even then, with 

 two tuber systems in the soil, they are connected by the top of 

 the sheath, the two flowers and leaves coming from the 

 identical vegetative stem. Later, the stem shcathings decay, 

 and there remain two separate plants, each with its pair of 

 tubers. Many years may elapse before this articulation, 

 uniting the two plants, disappears. It is not common, in this 

 State, for more than two tubers to be so united : but Dr. 

 Rogers states that in Western Australia the tubers of various 

 individuals are united curiously together, not in juxtaposition, 

 l)ut by actual articulation. This is there common with Glossodia 

 Brunonis. It is interesting to note that with this species there 

 are many tubers, all united by articulation, finally ending in 

 one stem near the surface. From this one stem comes quite 

 a colony of flower-stems and foliage. In Western Austraha 

 this articulation also occurs commonly with Caladenia 

 Patersoni. Again the tubers are articulated, finally uniting 

 in one stem before foliage and flower growth develops. This 

 articulation is not at all common in this State. 



In many species of Caladenia, particularly C. Patersoni, C. 

 dilatata, C. fdamcntosa, C. latifolia, C. Uptochila, and C. 

 cairnsiana, the sheathings that were noticed in Glossodia are 

 neither so plentiful nor so complete. The new parent tuber 

 may usually be seen developing through the base of the 

 sheathings. And in this way, year by year, the tuber grows 

 deeper in the soil. In its downward development the tuber 

 leaves behind the fibrous shells of other years, so that the 

 remains of the tubers may easily be noted on the root-stalk 

 which is extending from the tuber to the ground surface. One 

 plant of Caladenia dilatata was observed with the sheathing 

 shells of four older tubers, and five shells were found on a plant 

 of Caladenia latifolia. In i()i3 a plant of Caladenia Menziesii 



