postelsia 87 



passing comment here. The seeds at the time 

 of maturity are covered with a mucilaginous 

 substance. The bursting fruit shoots out the 

 seed with considerable force and as the flying 

 missile strikes a branch it adheres and is held in 

 place. When such a seed, stuck on to a young 

 hemlock branch, germinates, the young seedling 

 finds the substratum it wants and c^uickly estab- 

 lishes itself. Where the hemlock forms a large 

 element of the forest composition, there the ad- 

 vent of the parasite is especially dangerous, since 

 the trees stand in such close proximity to each 

 other as to facilitate the transfer of seeds from 

 one to the other. The other coniferous trees 

 of the region seem to be immune against this 

 mistletoe, for is was never observed upon any 

 other host than the hemlock. 



Another plant, a representative of the Oro- 

 banchaceae, which shows a peculiar parasitic 

 habit, is Boschniakia strobilacea. This is of 

 frequent occurrence in most places where the 

 salal, Gatiltheria shallou, abounds, for it grows 

 as a parasite upon the roots of this shrub. 

 It produces peculiar bulb-like almost spherical 



