PARASITIC FLOWKKING PLANTS. '!•') 



flowers, witli their rosultnnt socd-vessols. From the absence of 

 roots it is assmued that it derivos its nourishmcut, during its 

 subtorranoau existence, by absorption through its whole surface, and 

 at the proper season its flowering head is thrust above tlie soil. It 

 is possible that it has the power of secreting from its surface 

 a solvent which acts upon the surrounding humus and thus renders 

 soluble the elements needed for its support, which can then be 

 absorbed into its tissues. Analogies are furnished by the scutella 

 of the embryos of Monocotyledons, so far as the chemical changes 

 exerted upon its food are concerned, and by submerged aquatic 

 plants in their power of absorbing through their whole surface. 



Of this at least I am assured, that Monotropa has no roots, nor 

 is it attached by suckers to any other living plant, so that it 

 necessarily obtains its food by other means. Hundreds of plants 

 have been extracted from the soil by myself and my friends, and 

 although we have carefully delved down as low as possible, no 

 trace of roots could be detected whenever the base of the stem has 

 been reached. 



To avoid any misapprehension it may be expedient to say that 

 Epiphytes are properly outside our subject. They find lodgement 

 only on their host, their food being obtained chiefly from the 

 atmosphere, as in other green plants. They also derive a certain 

 amount of moisture from the rain which trickles down from the 

 branches above and is taken up by adventitious roots, as in ivy. 



It often happens that epiphytal flowering plants occur on polled 

 willows growing by the skies of streams. The seeds of these 

 epiphytes have been carried to such positions either by the wind or 

 by birds. The roots of these plants may sometimes be observed 

 running down the inside of the hollow trunks of the willow and 

 penetrating the soil at the base. 



Those who wish to carry further the study of this subject may 

 consult the following : — On parasitic flowering plants generallv : 

 'Science Gossip,' 1885, pp. 157 and 172 (A. T. Webster); Sach's 

 * Text Book of Botany.' On the mistletoe : ' Science Gossip,' 

 1876 (W. G. P.), 1877 (Edwin Lees), and numerous references in 

 the volumes for 1878, 1879, and 1880. From these sources the 

 following list of trees on which mistletoe has been found in Great 

 Britain has been compiled : — 



Tilidcece. — Lime. 



SapindacecB. — Maple, horse-chestnut (very rare). 



Leguminosce. — False acacia (^Rohhiia). 



Rosacece. — Hawthorn, pink hawthorn, crab-apple, orchard apple, 



pear (extremely rare). 

 Oleaceee. — Elm (rare). 

 Cupuliferce. — Oak (rare), hazel, filbert. 

 SalicinecB. — Black poplar, aspen, white willow. 



In the following list of British parasitic and saproplivtic 

 flowering plants those which have been observed in Herts, Beds, 

 and Bucks are specially indicated. It is noteworthy that there 



