RowLeE: Notes on ANTILLEAN PINES 107 
and relative amount of the summer wood in the annual ring, thereby 
increasing the weight per cubic foot and also the hardness of the 
wood, hence the name hard pine. They are the heaviest pine 
woods known, indeed there are, so far as the writer is aware, no 
other coniferous woods whose weight equals them. Their wood 
is as heavy as that of white oak. 
The ecological significance of the dense summer wood is, it 
seems to me, to be found in the necessity of these plants to adapt 
themselves to a very dry season. By its development the trunk 
of the tree is encased in dense layers of wood and the escape of 
water is thereby largely prevented. The dry winds and continuous 
heat of the region where the hard pines occur suggest that a re- 
sponse on the part of the plant might be expected. No soft pines 
grow under these conditions and other coniferous woods are scarce 
while the hard pines often form nearly pure forests. 
Another result of my observation was the discovery of an ap- 
parently undescribed species on the Isle of Pines and from the 
position of the scales when the cone opens I propose for it the 
following name: 
Pinus recurvata sp. nov. 
Trees of medium to large size with wide-spreading and rounded 
top ; bark of trunk vertically and horizontally fissured but not flak- 
ing off; wood very heavy (52 lbs. to cu. ft. when seasoned) : 
branches roughened by scars of bracts and needle-clusters ; bracts 
decurrent on the branch, brown with hyaline margins, recurved, 
deciduous above the prominent base, after the needles develop: 
sheath smooth, its scales ciliate on the margins, 0.5 cm. long ; 
needles gray, 3 in a fascicle, 20 cm. long, 2 mm. wide, rounded and 
12-striate on the outer, plane with prominent sharply angled midrib 
on the inner side, 6-striate each side of the midrib, finely and 
sharply serrate : cone when closed cylindrical, when open ovate, 
10 cm. long, 5 cm. thick at the base ; scales recurved, remaining 
compact at the base, 1 cm. wide, dark brown, apophysis inequilat- 
eral, slightly rounded and depressed, horizontal carina distinctly 
evident, umbo diamond-shaped, with a short straight prickle. 
In general appearance, and in leaves and vesture of the 
branches, this species agrees closely with P. palustris. The cone 
is, however, only one half as large, and the depressed umbo and 
Straight prickle are not like that species. Its cone is even more 
unlike that of P. heterophylla and P. Cubensis, The Mexican pine, 
