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peristome nearly identical in structure being probably of a 
common origin; also, that it is difficult on any other theory 
to account for the almost complete identity of the peristome 
in Dicranum, Fissedens, Campylopus, Dicranella, Cynodontium, 
Trematodon, Dichodontium, and Leucobryum. 
That gymnostomous mosses as well as peristome-bearing 
mosses existed in the upper Miocene age we have abundant 
proof. In reply to a request for information on this subject 
from Baron Von Miller, whose life-long investigations in 
botanical science constitute him the highest authority in the 
Southern Hemisphere, he, with his usual courtesy, informs 
me ‘that Geeppart found one Phascum in amber ; also, in 
amber, several species of Dicranum, as D. fuscescens, D. 
flaggillare, D. scoparium, and I). pellucidum; a Hymenos- 
tomum, which Schimper finds very similar to H. microstomum; 
two species of Polytrichum allied to P. urnigerum and P. 
septentrionale ; and a Catherinea allied to C. undulata. 
Schimper has described a Fontinalis from the upper Miocene 
formation, and Bragniart another from that geological age. 
Of Hypnum, several species have been found by Herrs 
Httingshauren, Unger, and Saporta in Schists; and Ludwig 
and Schimper discovered some Hypnums in lignite, in which 
also some species of Sphagnum occur.” After alluding to 
the special works of the above-mentioned authors, I am 
particularly referred to Schimper’s “ Paleontologie Vegetate,” 
a work we unfortunately do not possess in the Library. 
Jt is therefore evident that gymnostomous Sphagnum and 
Phascum, single-peristomed Dicranum, and the perfectly- 
developed double-peristomed Hypnum flourished side by side 
comparatively in the upper Miocene age. Had no Phascum 
or Sphagnum been in this formation we should have been in 
a better mood to embrace M. Philibert’s view; on the other 
hand, had no perfectly-developed Hypnum been there found 
we might have felt a little closer drawn to the old views of 
development from gymnostomous forms. 
Had moss-plants been as large as Sigillaria pachyderma 
we might have known more of their history, the little we 
have received creates the want for more. If the perfect 
double-peristome is the earliest structure, from what allied 
form can it have varied? Does it not appear more probable 
that the double-peristome has been developed by slight vari- 
ations, one small step at a time, through climatic influences, 
from the single-peristome ? May not the single-peristome, 
in like manner, be developed from the gymnostomous plant; 
the gymnostomous from the splitting capsule—the latter 
through leafy, then frondose jungermannia, lichens, fungi, or 
alge; and all from the unicellular organism; the primary 
organism originating from beyond the limit of present discovery ? 
