798 The American Naturalist. (September, 
giniana and many others also grow here. As might be ex- 
pected, it is a flora made up of species which are by no means 
confined to this particular place. Some of them flourish 
equally well upon the surrounding uplands; a few grow in 
the open moor; many grow in low grounds that do not have 
the vegetable accumulations characteristic of these swamps. 
THE DISAPPEARANCE OF SPECIES WITH THE MATURING OF THE 
BOG. 
The rareness of some of the bog plants attest the gradual 
disappearance of species from these places. Specimens of 
Listera australis were found by Father Wibbe at the Lily Marsh 
in New Haven in 1877, where he reported it as growing abund- 
antly.” The writer has visited the same place several times 
? Bull. Torr. Bot. Club, VI, 192. 
since 1888, and has failed to find it again. It is safe to say 
that it is not abundant there now. A few plants were found 
by the writer in “Granny’s Orchard,” in Palermo, in 1895. 
Here continued and careful search resulted in the finding of 
but a few plants. Dr. W. M. Beauchamp has found the same 
species growing at Mud Lake near Baldwinsville, Onondaga 
County. Here, too, only a few specimens were found. These 
are, so far as known, the only stations for this species north of 
New Jersey. It is significant that a considerable number of 
species, not only those that affect bogs, but some Upland ones, 
have the same general range as Listera australis. The most 
conspicuous of these are: Rhexia virginica, Nyssa aquatica, Erio- 
caulon septangulare, Triglochin maritima, Xyris montana, Scheu- 
chzeria palustris and several of the Utricularias. It seems a rea- 
sonable inference that formerly there existed in these regions 
conditions much more congenial to these plants; that then 
they were more abundant and continuous in their range than 
now, and that they have settled in the limited tracts which 
afford them a congenial home. The conditions which conduce 
to their persistency are no doubt complex. The main ones, 
however, seem to be a constant and abundant humidity in the 
air and abundant moisture in the soil, and, at the same time, 
a relatively even temperature throughout the year. Humidity 
