POLLINATION is accomplished by means of the wind. At the period of pollination the leaves are always so widely separated from one another, that the ovules can catch the pollen-grains carried to them by the wind; this is often effected by the mucilaginous drops which appear at the micropyle, and by the evaporation of which the pollen-grains are brought in contact with the nucellus. The entire cone grows considerably as soon as fertilisation has taken place, and the cone-scales in Pinoideæ close together so that the seeds while maturing are enclosed, and it is not until the seeds are ready for distribution that the cone-scales again become separated. In the Pinoideæ, the fully developed ovuliferous scales are hard and woody; and in this condition the collection of female flowers is termed a _cone_. In the Taxoideæ, true cones are the exception. 2–15 cotyledons are present, arranged in a whorl. The characteristic feature of this class is the abundance of _resin_, which is to be found in isolated cells (especially in the cortex), partly in intercellular glands or passages (both in the cortex and wood). _Taxus_ is the only genus which has no resin. There are about 350 species, mostly from the Northern Temperate zone (especially North America and Siberia), where they grow gregariously and form the most northern forests. The Juniper, Scotch Fir, and Yew are natives of Great Britain. This class may be divided into two families:-- 1. =Taxoideæ.= The ovules have either one integument, the external part of which is fleshy, and the internal hard and stone-like; or two integuments, of which the external is the fleshy and coloured “aril.” “Ovuliferous scales” are wanting. The cones are never woody, but are generally succulent, the bracts become fleshy, or cones usually are not developed. The seeds project more or less freely beyond the bracts. 2. =Pinoideæ.= The ovules have two integuments, the external one of which is leaf-like and becomes developed as the “ovuliferous scale”; if there are several of these in each flower they unite and form a “symphyllodium.” This may remain free or unite with the bract. The cones are most frequently woody, rarely succulent. The seeds are hidden among the cone-scales. Family 1. =Taxoideæ.= This family, considered to be most nearly related to the Cycadeæ, also made its appearance at a very early period. There is only one order. Order. =Taxaceæ.= The characters have been given above.