NATURAL ORDERS. 



253 



Fig. 178. 



regular. Sepals 4 or 5, persistent, the two exterior often 

 smaller. Petals 4 or 5, often with black dots, twisted in aesti- 

 vation. Stamens generally polyadelphous. Carpels 2-5, united 

 round a central or basal placenta ; styles the same number as 

 the carpels ; stigmas capitate or simple. Fruit fleshy or cap- 

 sular. Seeds usually indefinite, minute ; emhryo straight ; al- 

 humen little or none. 



a. Properties : the plants yield a resinous acid juice, and a bitter balsamic ex- 

 tractive matter. 



Geneea. — Hypericum, Ascyrum, Elodea, Parnassia. 



418. Caryophyllace.e, the Pinh Trihe. — Herhs^ with opposite, 

 entire leaves. Flowers regular, often terminal, sometimes ax- 

 illary. Sepals 4 or 5, distinct, or cohering in a tube. Petals 

 4 or 5, or sometimes wanting. Stamens as many as the petals 

 and opposite them, or twice as many. Ovary composed of from 

 2 to 5 carpels ; stigmas 2-5, sessile, filiform. Fruit a capsule 

 oj^ening at the aj)ex. Seeds usually indefinite ; emhryo periph- 

 eric, curved or coiled round the outside of a mealy albumen. 



a. Properties : the plants of this order 

 are usually insipid ; some are said to be 

 poisonous. 



Genera. — Dianthus, Saponaria, Sagina, 

 Arenaria, Stellaria, Cerastium, Silene, 

 Agrostemma, Lychnis, Cucubalus, Mollu- 

 go, Frankenia, Polycarpon, Stipuhcida, 

 Spergula, Anychia, Scleranthus. 



Fig. 178, a, section of the flower of 

 Dianthus caryophyllus ; s, stigmas which 

 are papillose along their inner surface ; 

 e, stamens; p, petals cohering with the ca! 

 stamens at their base ; o, the ovary with 

 central placenta and ovules ; c a, capsules 

 of Lychnis gifhago cut vertically ; /, the 

 seed cut vertically, showing the peripheri- 

 cal embryo surrounding the mealy albu- 

 men. 



419. Portulaoaceji:, the Purslane Trihe. — Succulent or fleshy 

 herhs.^ or shruhs. Leojves alternate or opposite, entire,, with- 

 out stipules, often having hairs in their axils. Sepals 2, coliering 

 at the base. Petals 5, distinct, or cohering in a short tube. 

 Stamens variable in number, sometimes as many as the petals, 

 and opposite them. Ovary 1-celled, formed by 3 united car- 

 pels. Fruit capsular. Seeds few or numerous, attached to a 

 central placenta ; alhmnen farinaceous ; emhryo peripherical. 



a. Properties : insipid, or slightly bitter. 



Oeneua.— Portulaca, Talinum, Calandrinia, Claytonia, Montia, Lewisia. 



420. Mesembryanthemace^, the Ice-plant Tribe. — Herlace- 

 ous or shrubby succulent plants. Leaves simple, opposite or. 

 alternate. Sepals usually 5, but varying from 4-8, more or less 



