ET EN, 
142 DR. R. R. GATES : A STUDY OF NORTH AMERICAN 
It would be very instructive to transplant N. americanum to California and 
vice versá, and observe the results in successive generations. 
A segregate from N. ossifragum has been described by Celakovsky * from 
Corsica as JV. Reverchoni. Ut differs chiefly in having squamous bracts at 
the base of the stem, larger flowers and longer erect pedicels, and in the 
hairs of the filaments, which inerease in length from below upwards. 
A remarkable peculiarity of the genus Narthecium is the dense pile of 
white woolly hairs on the filaments. This is probably a feature which is of 
no service to the plant, but which persists throughout the genus because 
of inheritance, and it very likely originated through a mutation; which may 
have been one of several mutations which gave rise to the generic characters 
of Narthecium. The specific differences as above outlined are chiefly of a 
quantitative nature, although the species are so widely separated in space. 
The variations which gave rise to these species have evidently been small, 
and many of them might very well be considered of quantitative nature. 
It appears that these are exactly the type of variations which Darwin con- 
templated in his theory of natural selection. Whether these small differences 
are actually of survival value may perhaps be doubted. The question could 
be settled without difficulty in this case by transplanting each species into 
the range of the others and determining whether it succeeds or fails in com- 
petition with another species in its native habitat. "While these morphological 
differences are small, it may well be that they are correlated with invisible 
physiological changes which are important in the economy of the species. 
The genus Narthecium was formerly placed in the family Juncacew. The 
differences between it and its nearest relatives. 7riantha and Xerophyllum, 
are, unlike the specific differences within the genus, sharp and distinctive, 
though T'fieldia and Narthecium are remarkably alike in habit. The latter 
is compared with Triantha + in the following table :— 
Triantha (Nutt.), Baker. Narthecium, Juss. 
No rootstock. A creeping rootstock. 
Flowers mostly in threes in a centrifugal Flowers in a terminal raceme, greenish 
panicle, white or greenish. yellow. 
Perianth-segments for the most part not Perianth-segments obscurely 3-5-nerved. 
nerved. 
Filaments slender. Filaments subulate, woolly. 
Anthers rounded, erect. Anthers linear-oblong, erect, introrse. 
* Oest. Bot. Zeitschr. xxxvii. (1887) 154, 
T Lophiola aurea, Ker, representing another monotypic North-American genus, is found 
in pine barrens from New Jersey to Florida. It is usually placed in the Hemodoracew, 
and is rather remote from Narthecium in many features, but suggests a resemblance in 
having tufts of wool at the base of the perianth-segments on which the stamens are 
inserted. The inflorescence and upper part of the stem are, however, also clothed with 
soft matted wool, as in Lachnunthes tinctoria, El. 
