430 BOTANICAL GAZETTE [JUNE 
proper, outside the outermost line of dunes, would reveal a 
greater salt content in the sand than was found in the boring just 
described, but such did not prove to be the case. On the Vir- 
ginia coast two borings, each to a depth of 9°", were made along 
the line marking the outermost limit of vegetation towards the 
waves, one only a few meters distant from the boring in the — 
breach in the outermost line of dunes just described, the other 
within a quarter of a mile of the first. In both cases the soil was 
a rather coarse quartz sand, with traces of decaying vegetable 
matter, quite moist to within 2-3°™ of the surface. The first 
boring was about 1.5™ outside the outermost line of dunes, and 
4-5™ above the limit reached by flood tide at the date of the 
examination. Small plants of Panicum amarum minus grew where 
the boring was made. Here the resistance given by the satura- 
ted soil indicated in the first 3° about 0.003 per cent. of water- 
soluble salts, in the second about 0.009 per cent., and in the third 
about 0.006 per cent. Hence the percentage of salt in the 9*™ 
of sand was only about one-fourth as great as in the opening in 
the line of outermost dunes. It corresponds very closely, inex- 
plicable though the fact may appear, with that of the dune 
covered with Uniola, which was still farther from the waves than 
was the opening through the dunes. The second boring on the 
outer beach was made amid small plants of Ammophila arenaria 
and Sa/sola Kali, about 5™ outside the outermost line of dunes 
and a considerable distance above the limit reached at that sea- 
son by flood tide. Here the electrical resistance of the saturated 
soil indicated about 0.004 per cent. of salts in the first 3%, 
about 0.003 per cent. in the second, and about 0.003 per cent. in 
the third. 
In the sands of the outer beach on the coast of Massachusetts 
two borings were made in July. The first sample for examina- 
tion was taken at the outer limit of vegetation, which in this 
case extended only abont 1™ beyond the seaward base of the 
low outermost dunes. A luxuriant growth of Ammodenia 
(Arenaria) peploides occurred there, with Aériplex arenaria and 
Ammophila arenaria near by. The soil was a nearly pure quartz 
sand, moist as usual just below the surface. The boring was 
