CRUCIFERJZ. 



221 



The proportion of Crucifera in the Southern Hemisphere is small. 

 Dropping the introduced species, there are about seventy in Chili, a 

 score in Columbia, thirty in Australia, and half a hundred in South 

 Africa. The Tropics are very poor in Cruciferce, which all but dis- 

 appear at the Equator. In the temperate regions of Asia, Europe, 

 and even North America their number increases enormously. The 

 Levant is the richest locality ; next come the two shores of the 

 Mediterranean and Temperate Europe. In California and Texas 

 the Crucifers are still pretty numerous, as well as in the Eastern 

 States. Their number decreases on going northwards, in both 

 Continents ;' moreover, here, as in other orders, there are generic types 

 spread nearly all over the globe, such as Nasturtium, Draba, Carda- 

 mine, Thlaspi, Erysimum, Sisymbrium, &c. ; others are peculiar to some- 

 times very limited regions : thus, in Australia, Blennodia, Menkea, 

 Geococcus, Stenopetalum ; in Tropical Africa, Heliophila, Chamira, 

 Brachycarpaea, Palmstruchia, &c. ; in Chili, Schizopetalon, Mathewsia, 

 Cremolobus, Menonvillea, Hexaptera. Other genera, usually monotypic, 

 are still more limited. Atelanthera, in West Thibet ; Parolinia, in 

 the Canaries ; Streptoloma, on the shores of the Caspian ; Porp/iyro- 

 codon, in New Granada ; Warea, in Florida ; Mancoa, in the Peruvian 

 Andes ; Bivoncea, in Sicily ; Morisia, in Corsica and Sardinia ; Hemi- 

 crambe, at Tangier ; Nothothlaspi and Pachycladon, in New Zealand ; 

 Prinylea, in Kerguelen's Land, &c. 



The properties of the Crucifers,- like their organization, are pretty 

 uniform. Many are used for food, owing to the deposits in their 



1 A. de Candoiee, in his Geographie Bo- 



tanique, has collected the numbers given by 

 various authors for the proportion of Cruciferce 

 to Phanerogams at large. In the different 

 countries of Europe it varies from 4 to 6 per 

 cent, generally. In Spain the percentage rises 

 to 7-5 (Boissiee). In Asia there are in Daouria, 

 6 (Ledeb.) ; North China, 4"5 (Bttnge); Japan, 

 2 (Zuccarini). Tn Africa: Egypt, 5 (Delile) ; 

 Algeria, 4"5 (Desf.) ; Madeira, 5 (Low.) ; 

 Canary Islands, 3 (Webb). In America : Nor- 

 thern States, 2 (Beck:); New California, 3-5 

 (Hook. & Arn.) ; Chili, 2 (C. Gat). The per- 

 centage always falls 1 below in hot countries, 



such as Tropical Africa, India, Timor, New 

 Guinea, Tropical America. Melville Island has 

 the largest known — 13-5 (R. Be.). The same 

 author also gives several Crucifers among the 

 species extending over at least a third of the 

 globe — viz., Capsella Bursa pastoris, several 

 species of Nasturtium, Cardamine hirsuta, Ery- 

 simum cheiranthoides . 



2 Guib., Drog. Simpl., ed. 6, iii. 672. — 

 Lindl., Fl. Med., 91; Veg. Kingd., 353. — 

 Exdl., EncUrid., 452. — Peeeiea, Elem. Mat. 

 Med., ed. 4, ii. p. ii. 576. — Rosenth., Syn. PI. 

 Blajjhor., 629, 1142. 



