DICOTYLEDONES— CALYCIFLOR.E 



337 



sloviacece, Cunoniacece, and Bibesiacece, in the order Saxifra- 

 gacecB^ and arrange the whole in the foUoiving sub-orders : — 

 1. Saxifragece. 2. Francoece. 3. Escalloniece. 4. Philadelphece 

 or Hijdrangece. 5. Cunoniece. 6. Rihesiea;. 



Distribution and Numbers. — They are exclusively natives of 

 the northern parts of the world, where they chiefly inhabit 

 mountainous districts, and sometimes grow as high as 16,000 

 feet above the level of the sea. Illustrative Genera : — Saxifraga, 

 Lin7i. ; Heuchera, Linn. There are about 320 species. 



Fig. 1104. 



•~^ 



Fig. 1105. 



Fig. 1106. 



Fi'j. 1104. Siuifraya trithc-fiiUtes. The leaves are trifid and wedge-shaped, 



and the flowers arranged in a cyme. Fig. 1105. Vertical section of the 



flower. Fi(/. 1106. Vertical section of the seed. 



Properties and Uses. — The plants of the order are all more 

 or less astringent. This is remarkably the case with the root of 

 Heuchera americana, which is much employed for its astringent 

 properties in the United States under the name oi Ahun-root. 



Order 123. Fraxcoace.e, the Francoa Order. — Character. 

 Stemless /ier&s. Leat'es exstipulate. Crt/z/x 4-partite. Petals 4:, 

 persistent. Stamens hypogynous or nearly so, four times as 

 many as the petals, the alternate ones sterile, and commonly 

 termed scales. Ovary sujierior, 4-celled ; ovules numerous; 



VOL. II. z 



