588 PART III. THE CfiASSlFICATlON OF PLANTS. 



The juice of the berries of Phytolacca decandra, a native of North America, is 

 used as a colouring-matter in the manufacture of wine and in other processes. 



Order 4. NycTAGiNACEJ]. Perianth a simple whorl, petaloid, 

 gamophjUous, 5-leaved ; the basal portion persists as an investment 

 to the fruit, often becoming succulent or woody : stamens in 

 greater or smaller numbers (1-30) ; when isomerous thej usually 

 alternate with the perianth-leaves, but are sometimes opposite to 

 them (Colignonia) : ovary monomerous, unilocular, with one basal 

 campylotropous ovule ; the flowers are surrounded by an involucre 

 or epicalyx of 3, 5, or many bracts, enclosing 1, 3, or many flowers. 



Mirahilis Jalapa, the Marvel of Peru, is an ornamental plant from America ; 

 the roots are often substituted for those of the true Jalap. Whilst generally 

 sepaloid, the involucre is petaloid in Bougainvillea where it encloses three 

 flowers, and in Tricycla where it encloses but one : in the la'ter case, as the 

 single flower appears to be terminal, the involucre may be more correctly des- 

 cribed as an epicalyx of bracteoles (see p. 494). The embryo of Abronia is 

 pseudo-monocotyledonous. 



Cohort VI. Asarales. Affinities doubtful. Flowers mono- or 

 ambi-sporangiate : ovary inferior : ovules numerous. 



Order 1. Aristolochiacej;. Flowers 3-6-merous, ambisporan- 

 giate : perianth of three connate petaloid segments forming a three- 

 lobed tube : stamens 6 or 12, with extrorse anthers : ovary usually 

 6-locular, with numerous ovules in two longitudinal rows along the 

 inner angles of each loculus. The minute embryo is enclosed in 

 the copious endosperm. They are herbs or shrubs, often climbing, 

 with large leaves. 



In Asarum europceum (Asarabacca) the three lobes of the perianth are equal ; 

 alternating with them ara three scales which probably represent a corolla : the 



twelve stamens (apparently in two whorls) 

 are free, and the connective is produced (Fig. 

 394). The annual shoots of the creeping stem 

 bear four catapbyllary leaves, two large petio- 

 late reniform foliage-leaves, and a terminal 

 flower. The lateral branches spring from the 

 axils of the uppermost foliage-leaf and of the 

 scales. In Aristolocliia, the Birthwort (see 

 Fig. 293, p. 456), the limb of the perianth is 

 obliquely lipped ; the six anthers are sessile 

 and aduate to the short style (see p. 518). 



A. Siuho is a climber frequently cultivatei : 

 Fig. 391. — Asarum euroixBum. . 



Longitudinal section of the flower ^- Clematitis, though not indigenous, is 

 (mag,); i> perianth. (After Sachs.) found wild in Britain, generally on ruins : the 



