212 A TEXT-BOOK OF BOTANY 
able to endure the cold of winter (Figs. 30 and 31). As 
there is no regular period for the fall of leaves, as in the 
deciduous trees, the trees are always clothed with them, 
and hence are called evergreens. A notable exception to 
the evergreen habit of conifers is that of the common larch 
or tamarack, which sheds its leaves every season. 
The great body of the plant is highly organized for work, 
with its roots, stem, and leaves, and an elaborate vascular 
system connecting them all. The wood of the conifers is 
peculiar in its very regular grain, splitting easily; and its 
generally “soft” character is quite distinct from the so- 
called “hard woods.” Throughout the body there are 
also numerous resin-ducts, whose contents give a peculiar 
aroma to the wood. 
123. Strobilii—The cones borne by the conifers are 
well known, and suggest at once the strobili of certain 
Pteridophytes. There are two kinds of strobili, however, 
one being the conspicuous seed-bearing cones of common 
observation, the other much smaller and much less per- 
sistent cones (Fig. 202). In Selaginella (§ 118), it will be 
remembered, there are two kinds of sporangia in a single 
strobilus; but in conifers these two kinds of sporangia are 
in separate strobili or cones. In describing the two cones 
the pine may be used as an illustration. 
The small cone (Fig. 202, d, and Fig. 203, 4) is made 
up of sporophylls that look like small scales; and on the 
lower surface of each scale there are two sporangia (Fig. 
203, B and ('), each sporangium containing very numerous 
small spores (microspores). All of these structures received 
names long before their relations to the lower plants were 
known; but as these names are well known it is convenient 
to use them. The small spores were called pollen grains or 
simply pollen; the sporangia containing them were called 
pollen sacs; and the sporophyll bearing the sporangia was 
called a stamen. The strobilus or cone, therefore, is a 
