Page:TheTreesOfGreatBritainAndIreland vol01.djvu/170

5. Sorbus. Ovary with 3 or 5 cells, styles free. Fruit crowned by the calyx, endocarp membranous or coriaceous. Leaves pinnate. Includes two sub-sections:—

Aucuparia, with 3-celled ovary and small globular fruit, and

Cormus, with 5-celled ovary and large pear- or apple-shaped fruit.

6. Aria. Ovary with 2 to 5 cells, styles free. Fruit crowned by the calyx, endocarp membranous, flesh granular. Leaves simple. Includes the whitebeam and its allies.

7. Micromeles. Ovary with 2 to 3 cells. Fruit small, globose, umbilicate, endocarp membranous or coriaceous, calyx-lobes deciduous. Leaves simple. Includes several Asiatic species.

 

Synopsis of the Principal Species in Cultivation exclusive of
Pears and Apples.

(Cf, Plates 43-45, where leaves of most of the species are shown.)

I. Leaves regularly pinnate, the leaflets being separate and never decurrent by their bases on the rhachis.

A. Aucuparia. Mountain ashes. Leaflets unequal-sided at the base. Fruit small, not exceeding ⅓ inch.

(1-3) Winter buds white-tomentose.

1. Pyrus Aucuparia, Gaertner. Europe, Northern Asia, Japan. Young branchlets and leaves pubescent, adult leaves glabrous or only slightly pubescent beneath. The common mountain ash.

2. Pyras lanuginosa, DC. South-eastern Europe. Only differs from the preceding in the adult leaves being densely woolly beneath.

3. Pyrus thianschanica, Regel. Chinese Turkestan. Young branchlets and leaves glabrous; adult leaves quite glabrous beneath and conspicuously veined on the upper surface.

(4-5) Winter buds shining, glutinous, glabrous or sparingly pubescent, the pubescence oppressed and of a rusty colour.

4. Pyrus americana, Torrey and Gray. North America. Leaflets long, narrow, acuminate, glabrous beneath.

5. Pyrus sambucifolia, Chamisso and Schlechtendal. Manchuria, North-East Asia, Japan, North America. Leaflets broader than in No. 4, obtuse or acute (not acuminate), more or less pubescent beneath.

B. Cormus. True Service. Leaflets nearly equal sided at the base. Fruit large, inch diameter or more.