178 PLANT DISTRIBUTION. 



On the mud near Perranwharf the Sea Star-wort {Aster 

 Tripolmm), appeared for the first time about six years ago, and 

 at the present time it flourishes more luxuriantly than in its 

 native habitats along the coast. Its presence is doubtless 

 attributable to the seed being brought in the coal barges which 

 are generally moored alongside the place where the plant grows. 



To the late Mr. B. Sampson we are indebted for a singularly 

 fine plant or two of Erica Mediterranea, the rarest of British 

 heaths. In Mr. Sampson's time this beautiful plant was largely 

 cultivated at Tullimaar, and from this stock the plants in question 

 originated. 



For the presence of the Fennel, near Ponsanooth Bridge, 

 the Large St. John's "Wort, now flourishing in three places • 

 the Yellow Bed-straw, occupying a hedge at Pelean Cross ; and 

 the common Star of Bethlehem, occurring in several places ; we 

 have an explanation in the fact that they occupy what, in the 

 long ago, were garden hedges. 



Geterach ojfficinarum, the Scaly Fern, concludes the list of 

 plant wanderers, which, to use an Americanism, have "come to 

 stay " in the valley. This is by no means a West Cornwall fern ; 

 and although we have no definite information as to how it got 

 into the Ponsanooth burying-ground, and on a garden wall at 

 St. Stithians, we may be assisted in our inquiry by a recent 

 occurrence at Tremough. A plant of the scaly fern was found 

 growing at this place on a wall near the stables. At first the 

 problem of its presence seemed inexplicable, but when I learned 

 that one of the servants had been cultivating the fern indoors, 

 and that at the seasonal cleanings the carpets were thrown across 

 the wall on which the wanderer grew, I took my cue and con- 

 cluded that to some adventitious cause we are indebted for the 

 presence of the fern in the Kennall Yalley. 



Equally interesting has it been to notice the advent, brief 

 struggle, and ultimate disappearance of other plants. 



About nine years ago, after some alterations to a hedge by 

 the roadside at the rear of Yale View, the Spotted Medick 

 {Medicago maculata), and the Shepherd's Needle {Scandix 

 Pecten- Veneris), appeared in large patches. The following 

 summer there was a diminution in the number of both. By the 



