(_Comptonia peregrina_) belonging to the _Myricaceæ_. These are usually aromatic, always woody plants, of which several species besides sweet fern grow in the United States.] Somewhat higher in the scale of plant life are those families that, while still lacking petals, do have sepals. Their flowers are for this reason much better protected against rain or other inclement conditions, which means that they are so much the more likely to reproduce their kind. At least two of these slightly more developed families cling to the habit of bearing some of their flowers in catkins, however. Other families are also found in other parts of the world, but in North America this group is represented by: [Illustration: TRANSPLANTING RICE IN JAVA (_Courtesy of Brooklyn Botanic Garden._)] [Illustration: A TEA ESTATE IN CEYLON (_Courtesy of Brooklyn Botanic Garden._)] _Betulaceæ_--The birch, alder, hazelnut, and hornbeam. Both staminate and pistillate flowers in catkins. Fruit a small one-seeded nut or a winged samara in the birch. All wind-pollinated. Six genera and about seventy-five species, nearly all from north temperate zone. [Illustration: FIG. 95.--LOW BIRCH (_Betula pumila_) A bog shrub of the _Betulaceæ_ or birch family. Most of them are tall trees with both male and female flowers in catkins.] _Fagaceæ_--The oaks, beech, and chestnut. All trees or shrubs with at least their staminate flowers in catkins. Fruit inclosed in a bur (chestnut and beech) or borne in a cup (the acorns of oaks). At least five genera and about 375 species, widely distributed. The habit of bearing some or all their flowers in catkins which flower usually before the leaves appear, and of having such flowers wholly at the mercy of precarious winds, is, if not lost, at least much less frequent in the remaining families of the apetalæ. All the others, while still without petals, do have sepals and some of these are colored so that insect visitors are likely. There are too many of these families to be enumerated here, but two of the chief are: _Ulmaceæ_--The elms and hackberry. Trees or shrubs with minute greenish or yellowish flowers crowded in small clusters or in spikes. Fruit a dry nut or one-seeded and winged; or in the hackberry a drupe, one of the first evidences of even a slightly fleshy fruit in the dicotyledons. About 13 genera and 140 species, widely distributed. _Polygonaceæ_--The buckwheat, knotweeds, common dock, and many other genera. Sepals often colored white or pink so the flowers are sometimes at least insect-pollinated. Flowers small and crowded in various clusters, often in a spike. Fruit an achene, a dry fruit familiar enough in the buckwheat. About 40 genera and over 800 species, mostly herbs or vines here, but often trees in the tropics.