140 
A RARE MOSS IN THE CONSERVATORIES. 
It is almost impossible, and in many cases undesirable, to 
keep the pots in the greenhouses free from various mosses and 
hepatics ; many plants grow better in wet moss or on peat, notably 
certain orchids and ferns. Among the mosses in the large green- 
houses of the New York Botanical Garden there have been several 
species which are quite common and have been brought in from 
the garden, especially Catharinea angustata, Physcomitrium tur- 
binatum and ae ee as well as the ubiquitous, 
often iniquitous, Marcha 
But besides these ae ones there are a number of rarer 
mosses and hepatics which do not grow elsewhere within the 
limits of the Garden and have probably been brought in either by 
spores or attached to plants introduced from the tropics. On 
one of the palms in the cool house (no. 13) there is a thriving 
and most interesting colony of a beautiful tropical genus Hypo- 
pterygium and in the orchid house (no. 15), on one of the pots of 
the Venus-slipper orchid, Paphiopediom, I discovered on January 
g of a small fruiting moss which proves to be a species 
of a rare tropical genus, ge ea probably the same as 
the species which was described by Mr. H. N. Dixon in the 
Journal of Botany for 1907, from plants grown in warm forcing- 
houses in England, also in a collection of orchids. Three times 
previous to this other plants of the same genus have been found 
in greenhouses, first at the Botanical Gardens at Glasnevin, Scot- 
land, in 1872, then in Cherbourg, France, in 1902, and in Eng- 
land in 1904. Our record is the fourth, but egies second in 
importance, for only one previous collection has been found 
fruiting. Ten species of this genus have os described from 
tropical America ranging from the West Indies to Peru and Chile, 
but it is very doubtful whether all these will stand the test of 
critical study and comparis 
The plants are eee aunutes matted together by brown 
rootlets, with small blunt leaves, usually entire, with the vein 
ending below the apex and the fruit erect on a slender terminal 
The peculiar character of the capsule is that its mouth 
