ASCLEPIAS. 195 



fruit, are native species, called Buckeye. Both are large 

 forest trees, with 5 leaflets and 4 petals. Other species are 

 shrubs, with red or purple panicles, often seen in shrubberies. 

 Classification. ^Esculus and Acer would seem, at first 

 view, to have little affinity with each other ; but of late, 

 botanists have included both, together with Sapindus 

 (Soapberry), Staphylea (Stafftree), and other genera equally 

 diverse in aspect, in the same order the SAPLNDACE^E, or 

 Soapworts. Their affinities are approximate rather than 

 identical, so that the ordinal character cannot be satisfacto- 

 rily formulated. 



The Soapworts comprehend 73 genera, 650 species, divided into 

 four suborders, found in all northern countries, and abundant within 

 the Tropics. 



Sapindus (sapo-indicus =. Indian Soap) gives name to the order. One 

 of its species, S. margindtus, called Soapberry, grows in Georgia and 

 westward. It is a small tree, with pinnate leaves, flowers in large 

 panicles, and berries reddish-brown as large as grapes, and full of a 

 soapy pulp. Other species in the W. Indies, more abundant in alkali, 

 are actually used in washing linen. 



PauUinia, of Brazil, affords the Guarana, a popular beverage resem- 

 bling tea in its effects. The seeds are dried, pulverized, kneaded into 

 dough, then dried in cakes for the market. 



Llll. SILK GRASS. 



Description. A stout herb a yard in height, surcharged 

 with milk-white juice, and bearing globular clusters of bloom 

 in June and July, is a sight familiar to the traveler in the 

 low-lands along the streamlet or wayside. The plant is 

 variously called Milkweed or Silk-grass. We shall leave the 

 student alone, to study for record the organs constituting the 

 leaf-region. The flowers and fruit present new and strangely 

 curious structures. 



