600 



THE BROOMRAPE FAMILY. 



greater and the clove-scented B. Stamens more or less hairy in their 

 lower part. 



One of the widest-spread species over Europe and Russian Asia, grow- 

 ing on a great variety of plants. In Britain, not uncommon in south- 

 ern and central England, and southern Ireland. Fl. all summer. It 

 varies according to station, and the plants it affects. Many of these 

 varieties have been considered as species, amongst which three are 

 commonly admitted into the British Floras : — O. Picridis (Eng. Bot. 

 Suppl. t. 2956), a tall, very pale-coloured variety, growing on the 

 Hawkweed Picris ; 0. amethystea, assuming a bluer tint than any of 

 the others, and growing on Eryngium ; 0. Seder ce ( 0. barbata, Eng. 

 Bot. Suppl. t. 2859), not uncommon on Ivy in the south of England 

 and Ireland as on the Continent. It is said to differ from the common 

 form in the yellow, not purple, colour of the stigma, and other trifling 

 characters, which however do not appear to be at all constant. 



6. Blue Broomrape. Orobanche cserulea, Vill. (Fig. 716.) 



(Eng. Bot. t. 423.) 



Stem simple or rarely branched, 6 to 

 9 inches high, with a light-bluish tint. 

 Flowers of a deep purplish-blue, with 

 two small bracts at the base, one on 

 each side, besides the larger bract com- 

 mon to all Broomrapes. Calyx usually 

 closed at the back by a fifth tooth or 

 lobe, much shorter and broader than 

 the others. Corolla- tube rather long 

 and curved ; the 5 lobes, although ar- 

 ranged in two lips, are less unequal, 

 and less wavy than in the preceding 

 species. 



Chiefly, if not exclusively, on the 

 Milfoil Achillea ; not uncommon on the 

 continent of Europe, and in west-cen- 

 tral Asia. In Britain, only in grassy 

 pastures near the sea, in Norfolk, and in 

 the Channel Islands. Fl. early summer. 

 The O. arenaria, a larger plant, of a 

 paler blue, parasitical on Artemisias in light, sandy soils, is said to have 

 been found also in Jersey ; but all the specimens so named from that 

 island which I have seen, have proved to be the blue B. 



Fig. 716. 



