364 REVISION OF THE GENUS PINUS. 
often again bears flowers. Male flowers sometimes abnormally make their appearance higher up on 
the axis mixed with leaf-bundles and occupying the place of such. The male flowers consist of an 
indetinite number of anthers sessile on a more or less elongated column, and have the form of an 
oval or a cylindrical ament, for which they used to be taken. They are surrounded by a some- 
what definite number of bracts, which assume the functions of a calyx and have been some- [168] 
times designated as such. Linneeus, in his Syst. Nat. ed. 1, speaks of a calyx 4-phyllus. 
Their number varies in the different species from 3 to 15 or 16, but is fairly constant in the same 
species. The two exterior lateral bracts are strongly keeled, like those of the sheath of the leaves, and 
stouter and mostly shorter than the others; the third is placed on the upper side, towards the axis 
of the inflorescence ; the fourth on the lower or dorsal side, opposite the supporting bract, and so forth. 
The innermost ones not rarely exhibit a transition to the anthers, bearing small or incomplete anther 
cells on the lower part of their back. In P. resinosa and Canariensis I find the involucral bracts 
articulated in the middle. 
A table exhibiting the numerical proportion of involucral bracts in the different species, the 
male flowers of which I could examine, may not be without value. 
3 or 4 involucral bracts I find in P. sylvestris and Pinaster ; 
3 to 6 in P. densiflora ; 
4 in P. Balfouriana, Canariensis, and Greggii ; 
4 to 5 in P. edulis and Parryana ; 
4to 6in P. Pinea and P. Halepensis ; 
4 to 10 in P. Pyrenaica ; 
5 to 6 in P. monophylia ; 
6 in P. leiophylla, Laricio, and contorta ; 
6 to 7 in P. resinosa, montana, and Massoniana ; 
6 to 8 in P. Strobus, excelsa, Peuce, Cembra, rigida, tuberculata, muricata, pungens, Banksiana ; 
8 to 10 in P. monticola, flexilis, insularis, Chihuahuana, Thunbergii, Laricio vax. Pyrenaica, and Austriaca, Coultert, 
tnOpS 5 
ones Teda ; 
9 to 12 in P. Montezuma and mitis ; 
10 in P. insignis ; 
10 to 12 in P. ponderosa ; 
10 to 15 in P. Sabiniana ; 
12 in P. Merkusii and Elliottii ; 
12 to 14 in P. Khasia, glabra, and australis ; 
14 to 16 in P. Lambertiana and Cubensis. 
The ANTHERS consist of two parallel extrorse cells, which open longitudinally on their back; 
their connective, heretofore often called a bract, spreads out into a transverse semi-orbicular or 
almost orbicular, entire or denticulate (in most species of Pinaster) or lacerate (P. Lambertiana) [169] 
crest, or it terminates in a knob ora few teeth (in most Strobi and a few Pinasters such as 
P. Balfouriana and sylvestris). 
The POLLEN has the well known bilobed form, consisting of an elliptic central portion, which 
emits the pollen tubes, and two lateral sacs which are said to contain air. The longer diameter 
. measures 0.025 to 0.045 line, mostly between 0.030 and 0.040 line, while the pollen-grains of 
Abies and Picea are much larger and in many instances twice as large, viz. 0.045 to 0.070 line long. 
Thus by the pollen alone Pinus can generally be distinguished from those allied genera. The 
different species of pines are pretty constant in the size of their pollen. 
Without going into minute detail, I will only state that I find pollen-grains of 
0.025-0.030 line in P. edulis and P. Banksiana ; 
0.030-0.035 “ in P. Balfouriana, sylvestris, montana, resinosa, Chihuahuana, Laricio, inops, contorta ; 
0.035-0.040 “ in P. Strobus, excelsa, Pinea, rigida, Tada, mitis ; 
0.010-0.045 “ in P. Lambertiana, flexilis, Montezuma, Pinaster, ponderosa, Sabiniana, Elliottii. 
