250 CONVOLVULACE^ 



and very succulent, styles included ; corolla with a globose tube, scarcely 

 longer than the bell-shaped calyx • scales closely pressed ; annual. This is 

 a naturalized and not a truly wild plant. It is abundant in Germany, and is 

 supposed to have been brought into this country with the imported flax-seed. 

 It is very injurious to the plant on which it is parasitic. Mr. J. E. Bowman 

 discovered the species in 1836 in some flax in a field near Ellesmere, in 

 Shropshire. He at first took it to be C. europcm, but finding, on further 

 examination, that the structure differed somewhat from that of that plant, 

 he forwarded it to Sir Wm. Hooker for examination. This botanist decided 

 it to be the species which is in Germany so very destructive to the flax crop, 

 stunting the growth of the stems by closely interlacing them, and he suggested 

 to the discoverer the probability that all Dodder plants found on flax in this 

 country would prove to be of this species, an opinion which subsequent 

 observations seem to have confirmed. 



The flowers in this species are large and succulent, more decidedly sessile 

 than in C. europcea, fewer in a head, very pale in colour, and of greenish rather 

 than reddish-yellow hue, with a membranous bract of a reddish colour under 

 each head, but none under each flower ; the calyx is large and spreading, its 

 five acute teeth about as long as the corolla. Like the stems of its congeners, 

 those of this Dodder turn from west to east, often embracing several flax 

 plants in their coils, and twisting them together as in a mesh of cords. 

 "Strictly speaking," Mr. Bowman remarks, "no station can be given for this 

 species, as it can only come to perfection where flax is cultivated ; for though 

 ripe seeds which have been shed upon the ground may germinate the ensuing 

 spring, the young plants soon die if the flax be not at hand on Avhich to fix 

 themselves. Accordingly, I could not find a single specimen in the same 

 field the ensuing summer, 1837, the crop having been changed. This may 

 account for a circumstance which occurred many years ago, and which 

 puzzled me at the time, and also confirmed Sir Wm. Hooker's opinion, that 

 it will only grow upon flax. I had sown some purchased flax-seed in a back 

 border in my garden, the plants from which were infested with C. europma 

 (as I believed) ; I sowed some of the Dodder seeds among nettles in the 

 corner of a field, and was disappointed at their not producing a single 

 plant, though I now think it probable that they germinated and died 

 away for want of their proper food. If botanists would search in fields 

 of growing flax, or among purchased seed in spring, they would probably 

 be rewarded by finding either living plants, or seeds of this troublesome 

 parasite, which I suspect is not uncommon ; and it would well repay the 

 farmer to rid his flax-seed of this worst species of tares before sowing it. 

 The seeds are large, nearly round, and would easily be detected among 

 the flax." 



Since the period in which this opinion was given it has become a well- 

 known fact, that the seeds of this Dodder are continually being imported 

 with foreign seed, often in company with the gold of pleasure, the darnel, 

 the three-horned galium, and other plants which trouble the farmer. 

 Professor Lindley, in some recent remarks on the subject, says also, that if 

 flax be again sown on the same land, it is astonishing, however few the 

 weeds might have been in the first instance, how greatly they become 



