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Almost all Crucifene have the calyx imbricated in aestivation ; but Mr. 

 Brown has noticed (Denkam, p. 7.) that in Savignya and Ricotia it is valvate. 



It is a very common character of Cruciferse to be destitute of bractece. 



Geography. An order eminently European ; 166 species arc found in 

 northern and middle Europe, and 178 on the northern shore or islands of the 

 Mediterranean ; 45 are peculiar to the coast of Africa, between Mogador and 

 Alexandria; 184 to Syria, Asia Minor, Tauria, and Persia; 99 to Siberia ; 

 35 to China, Japan, or India ; 16 to New Holland and the South Sea Islands ; 

 6 to the Isle of France and the neighbouring islands ; 70 to the Cape of Good 

 Hope ; 9 to the Canaries or Madeira ; 2 to St. Helena ; 2 to the West Indies ; 

 41 to South America ; 48 to North America ; 5 to the islands between North 

 America and Kamtchatka ; and 35 are common to various parts of the world. 

 This being their general geographical distribution, it appears that, exclusive of 

 species that are uncertain, or common to several different countries, about 100 

 are found in the southern hemisphere, and about 800 in the northern, or 91 in 

 the new, and the rest in the old world. Finally, if we consider them with le- 

 gard to temperature, we shall find that there are, — 



In the frigid zone of the northern hemisphere 205 



In all the tropics (and chiefly in mountainous regions) 30 



In the temperate zone \ °j ^ £8S £»■**?■ ■ «g J 6M 



Such were the calculations of Decandolle in 1821 (Syst. 2. 142). Although 

 requiring considerable modification, especially in the Siberian and North Ame- 

 rican numbers, which are much too low, they serve to give a general idea of 

 the manner in which the order is dispersed over the globe. 



Properties. The universal character of Crucifera? is to posses anti-scor- 

 butic and stimulant qualities, combined with an acrid flavour. These are so 

 uniform, that I shall only offer some very general remarks tipon them; for which 

 I am chiefly indebted to Decandolle's Essai sur les Propriety's JVIedicales des 

 Plantes, to which I refer those who wish for more information. Crucifera? con- 

 tain a great deal of azote, to which it is supposed is due their animal odour 

 when rotting. Mustard, Cress, Horseradish, and many others, are extremely 

 stimulating and acrid. The seeds of Sinapis chinensis are considered by Hin- 

 doo and Mahometan practitioners as stimulant, stomachic, and laxative. Jlins- 

 lie, 1 . 230. The seeds of one species of Arabis (chinensis Iioltler) are pre- 

 scribed by the Indian doctors as stomachic and gently stimulant ; but they 

 apprehend its bringing on abortion if imprudently given. Ibid. 2. 12. When 

 the acrid flavour is dispersed among an abundance of mucilage, various parts 

 of these plants become a wholesome food ; such as the root of the Radish and 

 the Turnip, the herbage of the Water-cress, the Cabbage, the Sea-kale, and 

 the stems of various plants of the cabbage tribe. Prince Maximilian, of Wied 

 Neuwied, relates that the Brazilian Indians use a kind of cress, which in taste 

 resembles that of Europe, as a good remedy for asthma. Travels, 1. 35. 

 Their seeds universally abound in a fixed oil, which is expressed from some 

 species, as the Rape, for various economical purposes. 



Linnaeus divided this order, which is the same as his Tetfadynaihia, by the 

 form of the fruit, under two heads, bearing the names of Siliquosa and Silicu- 

 losa. More recently, divisions have been founded upon the nature of the pli- 

 cature of the cotyledons, and the position of the radicle with respect to them. 

 It is difficult to say what degree of importance really deserves to be attached 

 to these characters, which are however in general use, and which will probably 

 continue to be employed for the purpose of distinction. 



The following are the modifications used by Decandolle 



1. The cotyledons arc flat, with the radicle lying upon their edges. (Pleu- 

 rorhizeee.) 



Examples. Cheiranthus, Arabis, Alyssum. 



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