416 



ILLUSTRATIONS OF THE NATURAL ORDKRS. 



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

 where the fruit is a foUicle. Ex. Spirasa and Gillenia. Tribe 2. 

 Dryadeje, where the fruits are achenia, or sometimes little drupes, 

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

 564, 565). Ex. Drjas, 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. Sllbord. Pomes {Pear Famjhj). Ovaries two to five, or rare- 

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

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

 several) ascending seeds. Trees or shrubs. — Ex. Crata?gus (the 

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



812 



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 

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

 kernel of Amygdalece contain prussic acid, or something of similar 

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



FIG. 808. Vertical section of an unexpanded Rose, showing the attachment of the carpels 

 to the lining of the cal3x-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 ovaries 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). 



