332 



Dodder. 



[SEPT., 



spread in all directions by means of its slender, thread-like 

 stems, which twine round the plants from which the pest draws 

 its sustenance. C. tri/oizi \s quite leafless, but produces clusters 

 of small white bell-shaped flowers, each of which yields a two- 

 celled capsule. Each cell contains two seeds, a single flower, 

 therefore, producing four. 



C. epithyiniLiii. — The flowers of this species are variable in 

 colour, and about \ to |-in. in diameter, opening from July to 

 October. The stems are reddish in colour and very slender. 

 It occurs in Britain from Ayr southwards, in Europe from Den- 

 mark southward, in North Africa, and in Western Asia. It is 

 also termed C. minor, or lesser dodder. 



C. eiiropaea. — In this species the stems are reddish or yellow 

 in colour, and as thick as twine, the flower-heads being from 

 4 to f-in. in diameter, and tinged with red. Flowering takes 

 place in Britain during the summer months, the species being 

 found from York to Sussex and Devon ; it is, however, rather 

 rare in Britain, It is also found throughout Europe, in North 

 Africa, and in Siberia. This species is also known as C. viajor^ 

 or greater dodder. 



C. epilinuin. — This species, flax dodder (PI. II.), occurs 

 sporadically on flax in Great Britain and Ireland, and is distri- 

 buted throughout Europe. It is as large as the last species, 

 but is paler and more succulent. It flowers during summer. 



C. Gronovii. — This parasite, known as large American 

 dodder, was identified in France by M. Schribaux some twenty- 

 five years ago, when it appears first to have been introduced 

 into that country from Canada or the United States. Owing 

 lo the fact that the seeds are about the same size as those of 

 lucerne, they are with difficulty separated therefrom, and this 

 renders the pest more dangerous. It is not believed th"at this 

 species ripens its seeds in this country, but the seeds germinate 

 when sown, and produce dodder plants which are quite able to 

 kill their host plant. 



C. vionogyna and C. corymbosa {C. Hassiaca, or C. snavcoleiis 

 are also harmful to certain plants. The latter is of American 

 origin, and bears large seeds. 



Life History. 



The embryo of the dodder seed is simple and thread-like, and 



