102 BOTANICAL GAZETTE 
earlier given, that there is an abrupt physical difference be 
the beaches of these woods and those outside, a difference w 
I feel sure, is one of age. The position of the zone would in 
mineral supply, and shelter than the zone outside, with wh 
large size of the trees is in agreement. But the bigness of 
makes the barrenness of the beaches all the harder to expla 
mats in the slopes and hollows with their well-grown white spt 
The mats, however, are no longer entirely creeping, for the j 
send up numerous erect shoots. With them persist seve 
plants from the transition zone, especially the rock cranbet 
three-toothed cinquefoil, the pearly everlasting, and a few 
But in addition new forms come in, especially and characte 
the bearberry, Arctostaphylos Uva-ursi, a rocky-hill plant, here 
carpet which we may best consider under the next section. 
themselves are of moderate size, rarely if ever over 20 feet in 
A fact of interest about the juniper mats, applying also to 
degree to the forest mat which succeeds it in the closed woods, 
its very slight hold upon existence on the sand, for where 
cross and disturb it, the entire mat dies and soon disappears. 
instability shows forcibly how hard are the conditions of life in 
situation, and how narrow the margin between success and fail 
THE CLOSED WOODS. 
The climax of the sand-plain vegetation is reached in the ¢ 
though dwarfed mixed woods extending between the sandy woods 
the upland. A typical view of the clcsed wocds is shown by iis. 
