•Linnean System of Plants, 



431 



sort of cluster is also called a catkin^ from its resemblance 

 to a cat's tail. Some persons reckon another cluster, called 

 the thryrse ; but this is merely a fuller kind of panicle, which 

 assumes an ovate (egg-shaped) form. 



We will now commence with the fourth class of plants, 

 Tetrdndria, distinguished by the four stamens in its blossoms. 

 Some genera of this class might, at first sight, be confounded 

 with those of the fifteenth ; but the number of stamens would 

 soon clear up any mistake of this kind ; and when we treat 

 of that class, we shall mention other distinctive characters. 

 This class has three orders ; Monog^nia, Digynia, and 

 Tetragynia. Of the first order, we have fifteen British ge- 

 nera; among which are the teasel, scabious, madder, bed- 

 straw, plantain, cornel, &c. Of the teasel, one species is used 

 by clothiers to raise the nap of woollen cloth ; whence it bears 

 the name of Fuller's Teasel. It is a singular-looking plant, 

 with a thick stem, 5 or 6 ft. high, clothed with several pairs 

 of leaves at regular intervals : they are so combined (not 

 only at the extreme base, but at their sides also, for an inch 

 or more) as to form a sort of basin round the. stem. Such 

 leaves are botahically termed connate (con, together, fiatus, 

 born, or grown). The reservoirs formed by their union col- 

 lect the rain ; sometimes containing half a pint or more ; 

 which sustains the plant during long drought. In desert coun- 

 tries, the weary and fevered traveller would sometimes ex- 

 change the whole of his property for the luxury of a draught 

 from one of these water-lodging plants ; but in this country 

 the moisture is of more use to the plant itself than to the 

 passenger or the possessor. The flowers are collected into 

 conical heads, about the size of a hen's egg, upon a receptacle 

 set with a number of chaffy scales hooked at their edges. 

 { fig, 193.) When the flowers wither, ^^ife. 193 



these heads are set in frames, and 

 drawn over woollen cloth to raise the 

 nap ; for which purpose the scales 

 have just sufficient strength, yielding 

 before they reach the cloth itself. 

 This operation is called teasing, from 

 which, most probably, the plant ob- 

 tained its name. The botanical ap- 

 pellation, Z)ipsacus, is derived from 

 the Greek, dtpsa, thirst; though the 

 plant is rather a reliever, than a re- 

 presentation, of thirst. 



The scabious also bears its flowers in heads, although in 

 some of the species they are rather hemispherical than glo- 



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