REVISION OF THE GENUS PINUS. 367 
serotinous cones seem to retain their germinating power for many years longer than loose pine seeds, 
which are known soon to lose their vitality. 
The SEEDS are obovate, or often more or less obliquely triangular, rarely (in P. Sabiniana and 
Gerardiana) nearly cylindrical, generally somewhat compressed, 2 to 12 lines in length, smooth or 
often on the lower surface ridged or slightly tuberculated, always destitute of balsam vesicles, pale 
gray or yellowish, or spotted, or brown, and often black. A wing is always present, and is generally 
several times longer than the seed; in some large-seeded species (P. flewilis, Cembra, edulis, and the 
other nut-pines, and Pinea) it is reduced to a narrow rim, which is apt to remain attached to the scale 
when the seed is liberated; in P. parviflora, Bungeana, Gerardiana, Torreyana, and Sabiniana, it is 
more conspicuous, but shorter than the seed itself; in P. Coulteri it is about as long as the seed, and 
in P. Lambertiana longer. The size of the seed and the proportion of the wing to it has been con- 
sidered to furnish valuable sectional characters, but it proves to be only of specific importance. The 
wing is always more or less oblique and widest in some species upwards, in others near the base. The 
base of the wing forms a rim which surrounds the seed, leaving its under side free and with its edge 
covering part of, or rarely the greater part (P. Hlliottiz) or the entire upper side (only seen in P. 
Banksiana). Generally the wing and its rim is completely separable from the mature seed, but in a 
few species (P. Strobus and allies) it adheres to it closely, and is at last broken off irregularly. 
The CoTYLEDONS, 4 or 5 to 15 or 18 in number, are mostly several times shorter than the 
caulicle, usually not longer than its diameter, and rarely as long or a little longer than it; this [174] 
seems to be the case especially where the leaves also are of unusual length, e. g. in P. australis. 
It is easy enough and very satisfactory to ascertain the number of cotyledons where a large 
quantity of seedling pines is at one’s disposal. With me this was unfortunately not the case ; hence 
I had to examine the seeds themselves, quite a laborious process, rarely extending over more than 
six or eight specimens, and often less. In examining greater numbers more variation will probably 
be discovered. As it is, the different species show a tolerable constancy in the number of their coty- 
ledons. I give here only the result of my own observations, leaving out those found in the books. 
I have observed — 
about 5 reese in P. Balfouriana, montana (3-6), Laricio, rigida, inops (4-6), muricata (4-5), glabra (5-6), 
Banksia 
about 6 avian in P. Balfour. var. aristata (6-8), resinosa (6-1), sylvestris (6-8), insignis (5-8), tuberculata 
(5-8), Teda (5-8), pungens (7), Pinaster (5-8), m 
about 8 cotyledons in P. Strobus (7-11), monticola (6-9), socio (8-10), flezilis (8-9), monophylla (7-10), edulis 
(7-10), Parryana, Halepensis (6-9), ponderosa (6-11), Canariensis, australis (7-10), Elliottii (6-9) ; 
about 10 cotyledons in P. excelsa (8-12), Peuce (9-10), Cembra (9-12), cembroides (9-12), Bungeana (11); 
about 12-15 cotyledons in P. Ayacahuite (12-14), Lambertiana (12-15), Pinea (10-14), Torreyana (13-14), 
Sabiniana (12-18), Coulteri (10-14). 
In germination the seed-shell is raised like a hood on the tip of the cotyledons, mostly after the 
wing has come off, but sometimes the wing is raised high above the plantlet (P. australis). The axis 
generally soon elongates, bearing the primary leaves, but the species just mentioned behaves pecu- 
liarly in this period, almost as do many monocotyledonous trees. For six or eight years it grows not 
in length but only in thickness, and bears in the axils of the short primary leaves numerous tufts of 
long and slender secondary leaves, which give the plantlet the appearance of a coarse grass or a rush ; 
only after it has acquired sufficient vigor the thick axis rapidly shoots up. 
1 Seeds from closed cones of P. contorta, two to eight years old when I collected them in Colorado, and then kept four 
years in a hot garret, germinated freely with Prof. Sargent of the Arnold Arboretum, Mass. 
