PARASITIC PLANTS. 175 



leaf -mould, or upon the decayed bark of old tree- 

 trunks. The embryo, which lies embedded in the 

 albumen of the one-celled seed, is in the form of a 

 thread and rolled spirally. It forms a circle of 

 a single turn or a turn and a half, and is thickened 



FIG. 43. CUSCUTA EUROP/EA, PARASITIC ON THE HOP. (Natural Size.) 

 (" Pflanzenleben.") 



at one end in the shape of a club. There is not a 

 trace of cotyledons in the true species of Cuscuta. 



" The seed lies on the ground in the open air all 

 through the winter, and germinates very late in 

 the following spring, at least a month later than 

 the other seeds .which have reached the same spot 



