274 SCIENCE. OF AGRICULTURE. Part II. 



1 785. The edible roots of the old world are chiefly the yam, sweet potato, onion, carrot, 

 and turnip ; of the new, the potato. 



1786. The oleraceous herbs of temperate climates are chiefly the J9rassica family, and 

 other Crucifera2. In hot climates potherl)s are little used. Legumes, as the pea, bean, 

 and kidneybean, are in general use in most parts of the old world. 



1787. The fruits of the northern hemisphere belong chiefly to the orders of Pomkceas, 

 ^mygdalineB, Grossulsurise, Rosacea;, Fiticeae, and Amentaceae. 



1788. The fruits of the East Indies belong chiefly to Myrtaceas, Guttiferffl, Aurantiaceae, Musace^, 

 Palma, Cucurbit^ceas, Myristiceas, &c. 



1789. The fruits of China are chiefly of the orders of Aurantiaceae, Myrtaceee, .Rhamneae, Pomaceae, 

 .^mygdalinece, Pahnce, &c. 



1790. The fruits of Africa belong to Sapbteie, Palmae, Chrysobalaneae, Guttiferse, .^pocyneae, Papilionkceje, 

 Muskcets, and CucurbitJlces. 



1791. The fruits of South America belong to Anonhce<s, Myrtaceae, rerebintaceEe, Myristicea;, PalmEB, 

 Broraebace^, Sapbtea^, Laurinea?, Chrysobalaneae, Mushcece, Papilionacea, and Passifibreae. 



1792. The most shoivy herbaceous foioers of the temperate zone belong to Roskcess, 

 iiliaceaj, /ridea?, ^ricinese, iJanunculacea?, Primulaceae, Caryophylleae, GentianeeB, &c. 

 Those of the torrid zone belong to the ScitaminccE, AmaryHirfe<^, l&ignoniacece, Mela- 

 stomkceae, Magnoljace*^, Papilionacese, ^pocynese, &c. 



1793. The most useful timber trees of temperate climates are of the pine or fir kind ; of warm climates, 

 the palm and bamboo. The universal agricultural order is the Graminete. 



Sect. VIT. Arithmetical Distribution of Vegetables. 



1794. Tlf.e total number of species of plants known, amounted in 1820 to about 44,000, 

 of which 38,000 have been described. According to Humboldt and R. Brown, they 

 are thus distributed: in Europe 7000; in temperate Asia 1500; in equinoctial Asia 

 and the adjacent islands 4500 ; in Africa 3000 ; in temperate America, in both hemi- 

 spheres, 4000; in equinoctial America 13,000; in New Holland and the islands of the 

 Pacific Ocean 5000 ; in all 38,000. In Spitsbergen there are 30 species of perfect 

 plants; in Lapland 534; in Iceland 533; in Sweden 1299; in Scotland 900; in Bri- 

 tain upwards of 1400; in Brandenburg 2000; in Piedmont 2800; in Jamaica, Mada- 

 gascar, and the coast of Coromandel, from 4000 to 5000. It is now (anno 1829) 

 believed that there may be from 100,000 to 200,000 species of plants. Such is the 

 progress of discovery and of ideas. 



Sect. VIII. Distribution of the British Flora, indigenous and exotic. 



1795. Nearly thirty thousand species are enumerated in Loudon's Hfirtus Britdmiicus, 

 including all the indigenous species of ilfusci, i^ungi, Fnci, A'lgae, and iichenes. 



1796. The natives of Britain, flowering plants, which enter into this Hortus are 

 upwards of 1400 species; but the native British Flora contains in all above 3300 

 species. Of these there are about 1437 cotyledonous plants, and nearly 1893 imperfect, 

 or what are termed, in the Jussieuean system, Acotyledoneae. 



1797. Of the cotyledonous or perfect plants, 182 are trees or shrubs; 855 are peren- 

 nials; 60 are biennials; and 340 annuals. Of the trees and shrubs, 47 are trees; 25 

 above 30 feet high, and the remainder under 30, but above 10 feet high. Of the peren- 

 nials 83 are grasses ; the next greatest number belong to the first two orders of the 

 class Pentdndria ; the next to the Syngenesia ; and the third to Monoe"*cia Triandria, or 

 the Cyperaceae of Jussieu, comprehending chiefly the genus Carex. Most of the bien- 

 nials belong to the first order of the 1 9th class, and the first two orders of Pentandria. 

 There are 41 annual grasses ; 52 annuals belong to the first two orders of Pentandria; 

 and the next greatest number of annuals to Diadelphia Decandria, which includes the 

 trefoils and vetches. 



1798. Oi the acotyledonous, or imperfect plants, 800 are Fungi; 18 A'lgse; 373 

 iichenes; 85 Hepdticae ; 460 ilfusci ; and 130 i^ilices; according to a rude estimate 

 formed in 1820. 



1799. In regard to the distribution of the perfect plants as to elevation, little or nothing 

 has been yet generalised on the subject. In regard to soils, 276 are found in bogs, and 

 marshy or moist places ; 140 on the sea shores ; 128 in cultivated grounds; 121 in mea- 

 dows and pastures ; 78 in sandy grounds ; 76 in hedges and on hedge banks ; 70 on 

 chalky and other calcareous soils ; 64 on heaths ; 60 in woods ; 30 on walls ; 29 on 

 rocks ; and 19 on salt marshes ; reckoning from Galpine's British Flora, 1820. 



1800. In the distribution of the imperfect plants, the jPilices prevail in rocky places and 

 wastes ; most of the JWusci, JTepaticse, and Xichenes, on rocks and trees ; most of the 

 Fuel and ^'Igae in the sea ; aqd of the i^ungi, on decaying vegetable bodies, especially 

 trunks of trees, manures, &c. 



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