489 



chusa sempervirens, Atropa Belladonna, Lathyrus maritimus, Mentha 

 piperita and Teucrium Chamaedrys ; and among the lattei* Cineraria 

 campestris, Diotis raaritima, Gentiana campestris, Gnaphalium sylva- 

 ticum and Scilla verna. 



The circumstances T would more particularly narrate have for their 

 subject the Chlora perfoliata. It was in 1841 that I first became ac- 

 quainted with this plant, which was then growing plentifully on the 

 calcareous clay on the sea-shore between Ryde and St. Clare. In 

 consequence of a notice which I saw, — I think in Mrs. Loudon's 

 ' Ornamental Annuals,' I was desirous to obtain seed of it for cultiva- 

 tion in the flower-garden, but when the blooming season in 1842 

 came, there was not a plant in existence. In 1843 the same thing 

 occurred, and I suppose I was satisfied with the idea, that the sea 

 had washed away all the soil on which the plants grew, for I thought 

 no more on the subject. However, in 1844, while strolling over the 

 clay, I was agreeably surprised to observe plants in bloom in the 

 greatest abundance. During the past year, 1845, I frequently search- 

 ed for it, but the whole number of plants found was three, and these 

 so starved and melancholy looking, as rather to excite pity than ad- 

 miration. 



In this narrative there are two things worthy of being taken into 

 consideration : the great decrease in the quantity or total disappear- 

 ance of the plant in some seasons, and the vitality of the seeds. The 

 first of these subjects will be attended in its examination with some 

 little difficulty, because the same effects do not happen to the same 

 plants in different localities, for, while the plant was scarcely found 

 last season at St. Clare, it might be found in great abundance on the 

 chalky ground and dry banks at Carisbrook. If the same effect had 

 been observed in both places, if the plant had been equally scarce at 

 Carisbrook as at St. Clare, we should have admitted, as good pre- 

 sumptive evidence, that some atmospheric peculiarity had been the 

 acting cause ; and the constitutional nature of the plant, which is 

 well known to gardeners to be impatient of moisture, would have ma- 

 terially strengthened the coincidence between the disappearance of 

 the plant and the cold and wet season of 1845, and between its plen- 

 tifulness and the warm and dry season of 1844. 



But while it is evident that we may not look to the atmosphere 

 alone for a solution of our subject^^ we may take it into consideration 

 in connexion with the state of the soil in each separate locality, and 

 if we find that there is a great and manifest degree of difference be- 

 tween the two, we may not look for equal results from them, even 



