DICOTYLEDONES : POLYPETAL^E : THALAMIFLOH.E. 



599 



morphic and pentamerous, sometimes monochlamydeous : calyx 

 often gamosepalous : stamens usually definite : ovary unilocular, 

 with basal placenta : seed with perisperm. 



Order 1. CaryophyllacevE. Flowers generally pentamerous, with 

 calyx and corolla, though the latter is suppressed in some cases ; 

 sepals distinct or coherent : stamens in two whorls (see p. 503), 

 of which the inner is often wanting ; ovary 2-, 3-, or 5-merous, uni- 

 locular, or multilocular at the base, with a central placenta or 

 with a single basal ovule : fruit usually a capsule : leaves opposite, 

 decussate : stems usually tumid at the nodes. 



Tribe 1. Alsinece. The corolla and the inner whorl of stamens are usually 

 present ; the calyx is eleutherosepalous ; fruit a capsule ; usually no stipules. 



The British genera are Sagina 

 (Pearl-wort), Arenaria (Sand- 

 wort), Cerastium, Stellaria 

 (Chick-weeds and Stitch-worts), 

 Spe rgula ( Spurrey ) ,Lepigonum , 

 Holosteum, Muenchia ; they 

 are mostly small herbaceous 

 plants with white petals, occur- 

 ring in meadows, on roadsides, 

 etc., but species of Lepigonum 

 (Spergularia), the Sandwort- 

 Spurrey, and Arenaria (Hone- 

 Icemja) peploides, Sea-Purslane, 

 grow on the sea-coast ; they 

 are distinguished from each 

 other principally by the number 

 of carpels present, and by the 

 mode of dehiscence of the fruit. 



Tribe 2. Silenece. The corolla 

 and the inner whorl of stamens 

 are always present : the calyx is gamosepalous ; stamens 10, filaments connate 

 at base : the fruit is a capsule (in Cucubalus a berry) : the leaves have no 

 stipules ; the floral axis is often elongated between the calyx and the corolla 

 (Fig. 403 y) : the petals (as in Lychnis and Saponaria) often have ligular ap- 

 pendages (Fig. 403 X : see p. 515). 



The species of Dianthus, the Pink, which commonly occur wild are I), deltoide^, 

 D. ctnsim and D. Armeria ; D. Carynphiflliis, the Carnation, and D. chinensis, 

 are well-known garden flowers : there are two styles, and the calyx is sur- 

 rounded at its base by bracteoles. The genus Saponaria has two styles but no 

 bracteoles ; S. officinalis, the Soap-wort, occurs on the banks of rivers. The 

 genus Silene (Catchfly) has three styles ; S. inflata, nutam, and others, are 

 common in meadows. The genus Lychnis (Campion) has five styles ; the 

 species alha {vespertina) and diurna are dioecious; L. GiUiago, the Coru-cockle, 

 is common in fields. 



Fig. 403. — Longitudinal section of the flower of 

 Lychnis Flos Jovis: y prolonged axis (anthophore; 

 see p. 494) between the calyx and the corolla ; 

 X ligular appendages or corona. (After Sachs.) 



