This great genus, which includes the Apple, the Pear, the Quince, the Service and the Mountain Ash, has been referred to in several preceding chapters. P. Aria is the White Beam Tree; there is a golden form, chrysophylla; P. baccata is the Crab (see Crab); P. Aucuparia is the Mountain Ash; P. communis is the Pear; P. Cydonia is the Quince; P. japonica (syn. Cydonia japonica) is the Japanese Quince; P. Malus is the Apple; P. pruni-folia is the Siberian Crab (see also baccata); P. Sorbus is the true Service Tree; and P. Termin-alis is the wild Service Tree. For references to P. floribunda, P. Scheideckeri and P. spectabilis see Chapters 9. and 26.; for Crabs see Chapters 9. and 15.; for the Mountain Ash see Chapter 9.; for Japonica, see Cydonia and Chapter 18. With respect to other Pyruses, the following are good garden trees: coronaria, the Canadian Crab and its double pink form flore pleno, which is both beautiful and sweet; Maulei, golden fruit, good for a low wall (see also Cydonia); sinensis, white flowers in spring; salicifolia, white, narrow lanceolate leaves, and its form pendula; and vestita, white, pyramidal habit.