THALAMIFLOR^. 237 



known as Linseed, yield a most valuable drying-oil, and their cake forms 

 an excellent material for fattening cattle. r !The flowers of many species of 

 Linum are very snowy (blue, yellow, pink, &c.), but are mostly fugacious. 

 The flowers of some are dimorphic. 



OXALIDACE^E. WOOD-SORRELS. 

 Series Disciflorse ; Tribe of Geraniaceae, Bentli. et Hook. 



Diaf/nosis. Herbs, or rarely shrubs or trees, with an acid juice; 

 mostly compound alternate leaves ; regular, symmetrical, hermaphrodite, 

 5-merous flowers ; calyx imbricated, and petals convolute in aestivation ; 

 stamens 10, somewhat monadelphous ; styles 5, separate ; capsule 5- 

 celled, several-seeded ; seeds perispermic : embryo straight or curved. 

 Radicle superior. Illustrative Genera : Oxalis, L. ; Averrhoa, L. 



Affinities, &c. Nearly related to Geraniacese, with which Bentham and 

 Hooker unite them. From Linacese they may generally be distinguished 

 by their compound leaves ; but the septa in the capsules of that Order 

 afford the most constant distinction. The seeds of Oxalis have an elastic 

 fleshy coat, which opens with elasticity and expels the seed when ripe. 

 Some regard this as an aril, others as a development of the testa. The 

 leaves of many kinds are sensitive, especially Oxalis sensitiva and Aver- 

 rhoa Bilimbi ; but others possess the quality in lower degree. O. bupleu- 

 rifolia and some other species have phyl lodes. 



Distribution. A rather large Order, the members of which are gene- 

 rally diffused in temperate and hot climates ; most abundant in America 

 and at the Cape of Good Hope. The shrubby kinds belong to hot climates. 



Qualities and Uses. The most marked property of Oxalis is the acid 

 juice, depending on the presence of oxalic acid. O. Acetosella, Wood- 

 sorrel, abounds in our woods. Averrhoa Bilimbi, the Blimbing, A. Ca- 

 rambola, the Carambole of the East Indies, have acid fruits, which are 

 eaten by the natives, but used chiefly as pickles by Europeans. Some 

 species of Oxalis have tubers furnishing wholesome food. O. crenata 

 (Arracacha) is used like potatoes in Columbia ; O. Deppei has roots as 

 large as small parsueps. The tubers of O. anthelmintica, the Mitcha- 

 mitcho of Abyssinia, are said to be valuable as an anthelmintic. Many 

 kinds are cultivated on account of the beauty of their flowers. 



GERANIACEAE. CRANE'S-BILLS. 

 Series Disciflorae ; Co h, Geraniales, Benth. et. Hook. 



Diagnosis. Herbs or shrubs, with articulated swollen stem -joints ; op- 

 posite or alternate leaves, and membranous stipules ; regular or irregular, 

 symmetrical, hermaphrodite, 5-merous flowers; sepals imbricated and 

 petals contorted in aestivation ; stamens mostly 10, coherent at the base, 

 the alternate ones shorter and sometimes barren ; carpels 5, adherent to 

 a central prolonged axis (carpophore), from which they separate when 

 ripe by the elastic curling-back of the segments of the style, carrying away 

 the 1-seeded dehiscent cocci (h'g. 361). Illustrative Genera : Erodium, 

 Herit. ; Geranium, Herit. ; Monsonia, L. ; Pelargonium, Herit. 



