REVISION OF THE NORTH AMERICAN HyYDNACEAE 101 
DISTRIBUTION. 
The geographical distribution of these plants appears to be 
largely influenced by latitude. But collections of basidiomycetous 
fungi from the region west of the Mississippi river have been so few 
and incomplete that general conclusions respecting distribution in 
this region can not be confidently drawn. The following areas 
may be recognized as possessing each a characteristic and some- 
what distinctive hydnaceous flora. (1) The northeastern United 
States south to North Carolina and Tennessee and west to the 
Great Plains. (2) The Southern States west to Louisiana. (3) 
The Gulf region including the West Indies and the immediate 
borders of the Gulf. (4) The north Pacific Coast including 
Oregon and Washington. It seems probable that Canada and 
. northern New England to Greenland may represent another dis- 
tinct floral distribution, but collections in this region have been 
too meager to suggest more than a possibility. These remarks on 
distribution are based on specimens actually seen by the writer 
and do not include the various species reported in catalogues and 
local floras without accompanying specimens. The material 
examined has come chiefly from the following states: Maine, 
Massachusetts, Connecticut, New York, New Jersey, West Vir- 
ginia, Ohio, Indiana, Kentucky, Alabama, Louisiana, Cuba, Hon- 
duras, Oregon, Washington. It will be seen therefore, that there 
are large areas of the country that have been scarcely explored 
for members of this group of plants. Even in the states quoted 
the collections are often from one or two localities only; thus 
Maine is represented only by collections at Orono and Mt. Desert, 
Ohio by collections in the Miami Valley, Indiana by work in the ` 
vicinity of Greencastle, and Alabama by collections made near 
Auburn. This study of distribution cannot be satisfactorily supple- 
mented by published local floras, for in consequence of the confused 
conception of species in this family such lists are wholly unreliable 
except when verified by actual specimens and these are often 
lacking. А comparison of two collections оп which such floras 
have been based, quickly reveals how utterly: untrustworthy are 
these lists of species as a means of determining distribution. Тһе 
plants referred to Hydnum imbricatum by Alabama collectors аге 
totally distínct from the plant referred to the same species by the 
