614 © Transactions. 
each pair, but also the fact that at intermediate altitudes intergrading 
forms are to be found which link up the two members in every important 
particular, point to one member in each of these pairs being a specialized 
form of the other. Additional data bearing upon this point will be no 
in my second paper. These pairs of species are—H. sanguinolentum and 
Н. villosum; H. flabellatum and Н. rufescens; Н. australe and Н. atro- 
virens; Н. Tunbridgense and Н. peltatum. It is to be further noted that 
H. villosum, H. rufescens, and H. atrovirens are endemic to New Zea- 
species, or whether, rather, they are not true species at all, but merely 
" forms" which preserve their distinctive character only so long as be 2 
gradation between the two forms. Also. alth i is. 
meio А . s ough the mountain form 18 
almost invariably restricted to the terrestrial a it may be found 
up, and of a bright green, contrasting strongly with the almost 
black curled fronds. Such young fronds are at first erect, with their 
