416 



ILLUSTRATIONS OF THE NATLTtAL OEDKRS. 



shrubs. — The three tribes of this suborder are : — Tribe 1. Spires, 

 where tlie fruit is a foUicle. Ux. Spirasa and Gillenia. Tribe 2. 

 Dryade^e, where the fruits are achenia, or sometimes little drupes, 

 and when numerous crowded on an enlarged torus (Fig. 558, 559, 

 564, 565). Hx. Dryas, Agrimonia, Potentilla, Fragaria (Strawber- 

 ry), Rubus (Raspberry and Blackberry). Tribe 3. Rose^, where 

 numerous achenia cover the hollow torus which lines the urn-shaped 

 calyx-tube ; and the latter, being contracted at the mouth, and be- 

 coming fleshy or berry-like, forms a kind of false pericarp ; as in the 

 Rose (Fig. 429, 808). 



813. Subord. Pomes {Pear Family). Ovaries two to five, or rare- 

 ly solitary, cohering with each other and with the thickened and 

 fleshy or pulpy calyx-tube ; each with one or two (in the Quince 

 several) ascending seeds. Trees or shnibs. — -Fx. Crataegus (the 

 Thorn), Cydonia (the Quince), Pyrus (the Apple, Pear, &c.). 



814. This important order is diffused through almost every part 

 of the world ; but chiefly abounds in temperate climates, where it 

 furnishes the most important fruits. It is destitute of unwholesome 

 quahties, with one or two exceptions, viz. : — The bark, leaves, and 

 kernel of Amygdaleas contain prussic acid, or something of similar 

 odor and analogous properties ; as is exemplified by the Cherry-Laurel 



riG. 808. Vertical section of an unexpanded Rose, showing tlie attaclimcnt of the carpels 

 to the lining of the calyx-tube, and of the stamens and petals to its summit or edge. 809. 

 Vertical section of the fruit of the Quince, exhibiting the carpels invested by the thickened 

 calyx which forms the edible part of the fruit ; one of the oraries laid open to show the seeds. 

 810. A magnified seed ; the rhaphe and chalaza conspicuous. 811. The embryo. 812. Cross- 

 section of an apple. 813. Flower, &c. of the American Crab-apple (Pyrus coronaria). 



