Peruvian mosses 
R. S. WILLrAMs 
(WITH PLATES 17-20) 
The following list is made up of two collections. The first, 
obtained by Harry Ward Foote, on the Yale Peruvian Expedition 
of 1911, was kindly forwarded by Dr. A. W. Evans of Yale. It 
consisted of forty-eight packets and contained thirty-seven species 
among which appear to be two novelties, also two species known 
before only from Patagonia. The specimens are from localities 
varying from about 900 to 3,300 meters in altitude. They were 
Without number, and I have accordingly rearranged and numbered 
them from 1 to 48. 
The second collection consisted of forty-three packets, ob- 
tained by Messrs. Cook and Gilbert, with the exception of three 
species by Hiram Bingham, while on the Yale University-National 
Geographic Society Peruvian Expedition in 1915. In this second 
collection four species are apparently new to science. I ma 
Say that it was through the codperation of the United States 
Department of Agriculture that Messrs. Cook and Gilbert were 
detailed to accompany this expedition and the specimens were 
forwarded to me by Mr. William R. Maxon of the United States 
National Museum. The altitude at which this second collection 
Was obtained varies from 1,800 to 4,100 meters, and there are 
thirty-three species not in the first collection, making agra 
species in this list. The type specimens of the new species are 
deposited in the herbarium of the New York Botanical Garden. 
Dicranum Mitrenr C. Miill. 
Above Arma Valley, July, 1915, H. Bingham 2063. 
I have not been able to find any publication of this species 
except that by Brotherus in Engler & Prantl’s Nat. Pflanzentam. 
(t: 328), under subgenus 4. It is a plant of medium size with 
the ovate leaf-base quickly narrowed to a long, subulate and 
serrulate point; the alar cells are numerous, those above in the 
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