PERSONA'J '&. 



517 



is sometimes destitute of cotyledons. The flowers are crowded 

 into capitulate inflorescences, complicated by accessory shoots 

 (Fig. 553 A) ; they have S5, P5 (imbricate aestivation), A5 (and 

 beneath the stamens 5 scales on the corolla-tube), G2. Fruit a 

 capsule opening by *lid.Cuscuta europcea, G. epilinum (Flax-Dod- 

 der), C. epithymum (Lesser-Dodder), G. trifolii (Clover-Dodder), 

 etc., are parasitic on different hosts, or parasitic each on its own 

 particular host. 



FIG. 553. Cuscuta trifolii, parasitic on Red Clover. A A portion of the stem with an 

 inflorescence and haustoria (mag.); B seed (nat. size); seed (mag.) ; D embryo (nat 

 size). 



840 species ; the majority in the Tropics, especially Am. Many are ornamen- 

 tal plants. OFFICINAL : some on account of their purgative properties : the 

 tuberous roots of Ipomcca purga (Jalap, from Mexico) and the dried latex 

 (" Scammony ") of Convolvulus scammonia (from the East). The tuberous roots 

 of Batatas edulis (Trop. S. Am.) are used as a common vegetable (Sweet Potato) 

 in the Tropics. 



Family 30. Personatae. 



The type of the flower is: S5, P5, A5 (of which one, or in 

 gome cases several, are suppressed), and G2. The flowers are 



