[ 74 ] 



jEquiectacc^: 

 Xifcv1bi6toi\\ antiquity of Zwc, etc. 



By W. G. Wheatcroft. 



Plates IX., X., XL 



THIS is the name of a natural order of cryptogamic plants, 

 which, whether regarded on account of their antiquity or 

 wide distribution over the face of the earth, are worthy of 

 careful consideration. This natural order contains only one 

 genus, Equisetum, or Horsetails. The generic name is derived 

 from eg'^^us, a horse, and sefa, a hair or bristle, in allusion to the 

 form of the stem. The Equisetum, Ephedron, and Anabasis of 

 Pliny are supposed to refer to one or other of the plants of this 

 genus. Equisda are found in most parts of the world, but there 

 are none in Australia or New Zealand. The tropics possess their 

 species as well as the more temperate climes. A few of the 

 species — as E. variegatum^ E. sylvaticum, etc. — have a very wide 

 distribution. E. variegatuni occurs as far north as Iceland. It is 

 also found in Quito, Bourbon, and Uitenhage ; whilst E. sylvati- 

 cum is found from the Arctic regions of North America to Simla. 

 E. giga7iteu}n, a Brazilian species, attains several feet in height, 

 and possesses a stout stem, three-quarters of an inch in diameter. 

 One species, on the contrary — E. debile — is so weak that it 

 requires the support of low bushes, up which it may be said to 

 climb, and Welwitsch describes E. dongatum as climbing up 

 Agave Americana at Lisbon. 



The properties and uses of Equiseta are few, whilst E. arvense 

 is chiefly known as a troublesome weed to farmers, especially on 

 ground which has been reclaimed from rivers, and in fields where 

 water stagnates in winter. Almost the only useful purpose to 

 which these plants have been put by man is that of polishing hard 

 wood, iron, brass, etc. E. /lyanale, commonly known as Dutch 

 rushes, is chiefly employed for this purpose. Carpenter states 

 that in some species silex constitutes not less than 13 per cent, of 

 the whole solid matter and 50 per cent, of the inorganic ash. It 

 abounds especially in the cuticle, hence its use for polishing. 



