244 



r)ipsXcE^ 



prominent, spinous inner bracts; involucel 4-angled ; calyx-tube 

 cup-shaped; petals 4, unequal. (Name from the Greek dipsao, 

 I thirst, in allusion to the water which usually collects in the 

 hollows formed by the pairs of united leaves. This serves as a 

 moat to prevent insects crawling up the stem to steal the honey 

 in the flowers, which is destined for flying insect visitors who will 



carry pollen from flower 

 to flower.) 



I. D. sylvestris (Wild 

 Teazle). — A stout plant, 

 3 — 6 feet high, with an 

 erect prickly stem ; 

 large, bright green 

 leaves, w^hich are prickly 

 underneath and united 

 at the base ; heads 

 large, conical, covered 

 with straight bristles ; 

 involucre curved up- 

 wards ; flowers lilac, 

 expanding in one or two 

 bands half-way up the 

 head and then both 

 downwards and up- 

 wards. — Waste places ; 

 common. — Fl. July — 

 September. Biennial. 



2.* D. F ullonum 

 (Fuller's Teazle) differs 

 from D. sylvestris mainly 

 in having a more cylin- 

 drical head, a reflexed 

 involucre, and hooked 

 bristles on the receptacle. 

 It is not known out of 

 cultivation, except as an 

 occasional escape, and 

 is probably only a form of D. sylvestris. 



3. D. pilosus (Small Teazle, Shepherd's Rod). — Smaller than 

 D. sylvestris in all its parts, rough with bristles ; leaves stalked, 

 with a small leaflet at the base on each side ; heads small, nearly 

 globose, drooping in bud ; involucre reflexed ; flowers white. — 

 Moist shady places ; not common. ■ — Fl. August, September. 

 Biennial. 



DiPSACUs SYLvfeTRis {IVild Teazle). 



