148 Rhodora [ AUGUST 
Growths of chestnut 150 years old, have a diameter of about twenty 
inches when growing singly, while in open places they frequently attain 
a diameter of three feet in sixty years, and sometimes grow very much 
larger than this. Chestnut, however, is usually cut for railroad ties 
when fifty or sixty years old, and about fourteen inches through, al- 
though this tree and the oak more often escape the woodman than 
does the pine. 
In considering the changes which have taken place, the question 
naturally arises, whether if the forests were left undisturbed they would 
return to their former condition. Undoubtedly this would eventually 
take place, but it would require more than three hundred years for the 
hemlock to regain its former habitat. The decline of certain species 
and the increase of others is largely due to the ruthless methods of 
deforestation which have been in vogue here from the very beginning. 
Were a scientific or rational system of forestry maintained, the forest 
growth would not undergo such abrupt changes, but would tend to con- 
form more to its primitive condition, and the entire floral condition 
would resemble quite closely that of old. From an economic point of 
view, the decline of the hemlock, and the increase of the birch and 
poplar is probably of not much importance. The most valuable trees, 
the pine and chestnut, are still common, and undoubtedly will remain 
so. However, there are still many hundred acres of old pasture that 
might be more profitably occupied by pine forests. 
AGRICULTURAL COLLEGE, Amherst, Mass. 
A NEW GRIMMIA FROM MT. WASHINGTON. 
E. G. BRITTON. 
(Plate 7.) 
Grimmia Evansi, spec. Nov. Plants forming low, dense, dirty 
tufts of a dark green or yellowish brown color, only the uppermost 
ends of the branches being green and free from gravel. Stems about 
15mm. high with short fastigiate branches 5mm. long, naked and 
radiculose below, crowded above with spreading leaves which are about 
1mm. long by 0.5—0.7 mm. broad, oblong, concave, acute or apiculate 
with inrolled margins above forming a more or less cucullate apex, the 
stout vein ending in or just below the point which occasionally is 
formed by a single short hyaline cell; apical cells rounded and indis- 
tinct, slightly sinuous, composed more or less of two irregular layers of 
