PASSIFLORIN.E. 475 



Other genera besides those mentioned are : Adenanthera, Des- 

 mantlius, Parkia, Inga (with rather fleshy, indehiscent fruit), 

 Calliandra, etc. 



1350 species (30 genera) ; none natives of Europe, their home being the 

 Tropics and sub-tropical regions, especially Australia and Africa. Fossils in 

 Tertiary. Gums are found in many species of Acacia, especially the African 

 (Gum arabic) and Australian, of which some are officinal. The bark, and also 

 the fruits, contain a large amount of tannic acid and are used as astringents and 

 in tanning (" Bablah " is the fruits of several species of Acacia). Catechu is a 

 valuable tanning material extracted from the wood of Acacia catechu (E. Ind.). 

 The flowers of Acacia fames i ana (Fig. 514) are used in the manufacture of per- 

 fumes. With us they are cultivated as ornamental plants, e.g. A. lopliantha and 

 many others, in conservatories. 



Family 22. Passiflorinae. 



The flowers are most frequently regular, 5-merous in the three 

 most external whorls, eucyclic and perigynous or epigynous, less 

 frequently hypogynous. A characteristic feature is that the 



FIG. 515. Passiflora ccerulea (reduced). 



ovary is tricarpellary, unilocular, and with 3 parietal placenta which 

 sometimes meet in the central line (Cucurlitacece) . The styles arc 

 generally free and bifid. To all these characteristics, however, 

 there are exceptions. The Cucurbitacese are sometimes placed among the 

 Syrupetalte, close to the Campanulas, but they are not allied to the S.ympetalas, 

 from which they differ especially, for instance, in the structure of the ovule. 

 The position of the Begoniaceae in this family is also open to doubt. 



