DODDER 37 



When looked at carefully, the stems will be found to bear minute 

 pointed reddish scale-leaves, which are so reduced as to have no 

 veins. 



Where the stem of the Dodder twines round the host it is 

 firmly attached to the latter. The attached portion is usually 

 thicker than the free regions. On pulling the parasite apart 

 from the host-plant small outgrowths will be found on the side 

 which lay against the host. These suckers or haustoria are borne 

 like roots on the stem of the Dodder, and actually penetrate the 

 tissues of the host. Their tips come into connection with the 

 conducting strands of the latter, which form the main lines along 

 which food materials are transported. The haus- 

 toria are thus in a position to obtain food material 

 from the host and convey it to the stem of the 

 Dodder. Since the Dodder thus obtains its food 



A B c 



FIG. 9. The Dodder. A, Plant in flower attached to the host plant ; B, complete 

 flower ; C, flower cut in half lengthwise. (After Baillon.) 



ready made, and has no need to obtain the raw materials and 

 manufacture its food from them as does an ordinary green plant, 

 we can understand the peculiarities of its vegetative organs. The 

 absence of roots, the minute size of the leaves, and the absence of 

 the green colouring matter by the help of which an ordinary plant 

 builds up its food when exposed to sunlight are all possible because 

 the Dodder gets its food direct from the host plant. 



The reproduction of the plant has, however, to be carried on, 

 and the flowers of the Dodder though small are perfectly con- 

 structed and show no reduction. They stand in little globular 

 clusters in the axils of most of the scale-leaves on the upper parts of 

 the shoots. Each flower, as Fig. 9, B shows, is composed of calyx, 



