168 Transactions. 



and spreading, and in those regions the appearance of the stem corresponds 

 more with the form A. In form C, however, the leaves are generally more 

 or less reddish in colour, the particular plant figured being a bright golden 

 red. The number of bulbils present is much greater than in the case of 

 the forest form, but is not nearly so great as in the case of the Macquarie 

 Island plant (Plate IX, fig. 2, B). There is a tendency for the sporangia to 

 be confined to fertile zones in the upper half only of the stems where the 

 leaves are of the short form. The tips of the branches where the sporangia 

 are full assume quite markedly a special strobilar appearance, as will be 

 Been by an examination of C, but this is only a pseudo-strobilar formation. 

 However, it is instructive to compare the tendency, as seen in this form of 

 the species, for the sporangia to be confined to the upper half of the stem 

 with what Cheeseman says (as quoted above) with regard to the Macquarie 

 Island plant. On the summit of Browning Pass, on the Southern Alps, at 

 an altitude of 5,000 ft., I collected specimens of L. Selago which showed two 

 very distinct forms. These are figured in Plate X, fig. 1, A, B. B corre- 

 sponds very closely with the tussock-country form just described ; but A, 

 while it is similar to the former in its much-branched nature and short 

 form, is yet very distinct. It is more flaccid in growth, and the leaves are 

 large, green, and spreading, as in the forest form of the species. The upper 

 parts only of the stem are fertile, and there is a very scanty development 

 of bulbils. Now, the form figured A grew among grass in a small cavity in 

 the ground partly sheltered by rocks, whereas that marked B grew in a 

 more exposed position on the surface of the ground, but only a couple of 

 feet distant from the other. This species must be in a very plastic state to 

 be sensitive to such a small change in the environment. 



To pass now to L. Billardieri. When growing as an epiphyte it presents 

 a very constant form. The plants occur in clumps and are pendulous, being 

 in extreme cases as much as 4 ft. or 5 ft. in length. They are abundantly 

 branched in all regions of the stems, so that the whole clump is quite bulky 

 in appearance. In the lower parts of the stem the leaves are large and 

 spreading, but there is a progressive diminution in their size in the ultimate 

 branches until the strobili are reached. The latter, however, are quite 

 distinct from the adjacent sterile regions of the branches, by reason of the 

 fact that the sporophylls are at once broadly ovate in shape, with a well- 

 marked keel, and are closely imbricating, and are also consistently arranged 

 in four orthostichies. The phyllotaxy of the strobili, joined with the 

 presence of the keel on the sporophylls, gives the strobilus a very distinct 

 tetragonous form. In Plate X, fig. 2, A, is shown a much-forked fertile 

 branch, alongside of which is the upper sterile part of the stem to which 

 it was immediately attached. C in the same figure is the fertile portion 

 of a branch of L. Phlegmaria Linn, from Fiji, from which it can be seen 

 that the difterentiation between fertile and sterile regions is more distinct 

 than in the case of L. Billardieri. A specimen of L. Phlegmaria from the 

 New Hebrides Islands which I have also in my collection shows the same 

 very sharp distinction between sterile and fertile regions, although in this 

 Ciase the sterile leaves are tenderer and the strobili are markedly finer and 

 more thread-like than in the Fiji form. Also in both these tropical forms 

 of L. Phlegmaria the sporophyll keel is much less developed than in 

 L. Billiardieri, so that the strobilus is cylindric rather than tetragonous in 

 form. In the extreme north of New Zealand I have frequently found 

 L. Billardieri growmg terrestrially amongst Leptospermum scrub on the 

 kauri-gum lands. These plants are from 2 ft. to 3 ft. in height, and the 



