THE POLYPETALOUS ORDERS. 423 



797. Subord, Hydrangea; (the Hydrangea Family). Shrubs. Pet- 

 als valvate in aestivation. Capsule two- (rarely five- to ten-) celled : 

 the styles or stigmas distinct or united. Stamens sometimes nu- 

 merous. Ex. Hydrangea, Decumaria. 



798. Subord, PhiladelpheSB (the Mock Orange Family). Shrubs. 

 Petals convolute in aestivation. Capsule three- or four-celled : 

 styles more or less united. Stamens mostly numerous. Ex. 

 Philadelphus, the Mock Orange. 



799. Ord, Hamamelaceae (the Witch-Hazel Family). Shrubs or 

 small trees, with alternate simple leaves, without stipules. Flow- 

 ers often polygamous. Petals valvate in aestivation. Stamens 

 twice as many as the petals, half of them sterile ; or numerous, 

 and the petals none. Summit of the ovary free from the calyx, a 

 single ovule suspended from the summit of each cell : styles two, 

 distinct. Capsules cartilaginous or bony. Seeds bony, with a 

 small embryo in hard albumen. Ex. Hamamelis (Witch-Hazel), 

 Fothergilla. A small order, of little importance. Hamamelis is 

 remarkable for flowering late in autumn, just a its leaves are 

 falling, and perfecting its fruit the following spring. 



800. Ol'd, Umbellifera; (the Parsley Family). Herbs, with hollow 

 stems, and alternate, dissected leaves, with the petioles sheathing 

 or dilated at the base. Flowers in simple or mostly compound 

 umbels, which are occasionally contracted into a kind of head. 

 Calyx entirely coherent with the surface of the dicarpellary ovary ; 

 its limb reduced to a mere border, or to five small teeth. Petals 

 five, valvate in aestivation, inserted, with the five stamens, on a disk 

 which crowns the ovary ; their points inflexed. Styles two ; their 

 bases often united and thickened, forming- a stylopodium. Fruit 

 dry, separating from each other, and often from a slender axis 

 (carpophore), into two indehiscent carpels (called mericarps) : the 

 faces by which these cohere receive the technical name of com- 

 missure : they are marked with a definite number of ribs (juga), 

 which are sometimes produced into wings : the intervening spaces 

 (intervals), as well as the commissure, sometimes contain canals 

 or receptacles of volatile oil, called vitta: these are the principal 

 terms peculiarly employed in describing the plants of this difficult 

 family. Embryo minute. Albumen hard or corneous. Ex. The 

 Carrot, Parsnip, Celery, Caraway, Anise, Coriander, Poison Hem- 

 lock, &c., are common representatives of this well-known family. 

 Nearly all Umbelliferous plants are furnished with a volatile oil or 



