186 I.INN.T.AN NATURAL SYSTEM. 



twisted in the bud contrary to the course of the sun, 

 its limb being wheel-shaped when expanded, in such a 

 way that each of its segments unequally proportioned in 

 their margin, is curved inward under the next segment, 

 the shorter side of the former being beneath the longer 

 one of the latter. Vinca or periwinkle, nerium or rose- 

 bay, asclepias or swallow-wort, &c. 



The plants have perennial roots ; leaves simple and undivided, 

 and with a very few exceptions, opposite ; sometimes ternate or 

 quaternate ; rarely alternate. The inflorescence is often peculiar, 

 in having its flower-stalks not axillary, but proceeding from the side 

 of the stem between the insertion of the leaves. Calyx of one leaf, 

 five-cleft; corolla of one petal, regular, its segments contorted, as 

 above described, and often notched in the margin ; nectaries in 

 many instances singularly formed ; stamens five ; pistils two, or one 

 with a double stigma; germen superior in most ; fruit in many, two 

 distinct follicles not observable in other plants. 



ORDER XXXI. VEPRECULjE. 



32. Derived from teprecula or little briar, and con- 

 sisting of plants resembling the daphne. Daphne, lach- 

 na;a, passerina or sparrow-wort, guidia, and so on. 



The plants of this order are known by their tough branches, silky 

 inner bark, simple entire leaves, acrid and even burning flavour and 

 sweet scented lowers, whose calyx and corolla are united into one 

 integument, most coloured within. 



ORDER XXXII. PAPILIONACEJE. 



33. This is an extensive and very natural assemblage 

 of plants, having papilionaceous or butterfly-shaped 

 flowers, embracing the leguminous vegetables, such as 



