Oil Dodder. 
253 
every means should be adopted to prevent undue moisture. No 
soil is exempt ; but there is less danger of an attack, and less 
injury when the disease makes its appearance, in thoroughly 
drained soils. 
VIII.— On Dodder. By W. Carruthers, F.R.S., Consulting 
Botanist to the Society. 
The dodders form a group of plants which are very closely 
related to the Bind weeds ( Convolvulaceoi), yet are separated from 
them by many important characters. Some fifty species are 
recorded from all parts of the globe, and though they can be 
specifically distinguished, no peculiarities exist among them of 
sufficient importance to justify the establishment of generic 
groups. All are included in the one genus Cuscuta established 
by Linnaeus. 
They are all annual parasitic herbs, with thread-like stems, 
entirely leafless, or having the leaves represented by a few 
scattered minute scales. The small reddish flowers are united 
Fig. 1. — Trefoil Dodder (Cuscuta cpithymum, var. Trifolii). 
into little round balls. Each flower produces four small seeds 
about the size of a grain of mustard. The mass of the seed 
consists of a fleshy albumen in which is spirally coiled a thread- 
S 2 
