1870.] for English Gardens. 353 



establish itself or again disappear after a few years. The " sowing " 

 of land with lime is invariably followed by the appearance of a crop 

 of white or Dutch clover. When certain kinds of wood are cut 

 down, it is said that during the next year a particular species of 

 moss will always be found covering the ground. Immediately after 

 the great fire of London in 1666, the London Kocket {Sisymbrium 

 Irio) sprang up in enormous quantities on the dismantled walls, 

 but is now no longer to be found in the metropolitan district. The 

 usual theory to account for this sudden appearance of new plants 

 is the existence in the soil of large " stores of seeds " ready to ger- 

 minate on the first favourable opportunity. In his Anniversary 

 Address to the Linnean Society in 1869, Mr. Bentham, however, 

 pointed out that if this explanation is the true one, it ought not to 

 depend merely on theory, but would be capable of easy practical 

 verification. He suggested whether a hitherto insufficiently acknow- 

 ledged part in the rapid dissemination of plants may not be played 

 by birds. The whole subject presents a wide field for further in- 

 vestigation, and must amply reward any one who takes up the 

 inquiry, if endowed with the qualities of accurate observation and 

 patient research. 



Mr. Mongredien's ' Planter's Guide ' deals chiefly with the intro- 

 duction into this country of foreign trees and shrubs. Within the 

 last twenty or thirty years the appearance of our lawns and planta- 

 tions has been greatly changed by the number of new forms which 

 have made their appearance. The stately Wellingtonia, the formal 

 self- asserting " Puzzle - monkey " or Araucaria imbricata, the 

 massive Deodar and Cryptomeria, the elegant Pinus insignis and 

 Cupressus Latvsoniana, are all still of too recent introduction to 

 permit us to judge of what their effect will be when grown to their 

 full stature. The number of cone-bearing trees from all parts of 

 the world, perfectly hardy in this climate, is extraordinary ; and, 

 partly from their graceful shape, partly from the evergreen character 

 of their leaves, the attention of cultivators has been perhaps too 

 exclusively confined to them, while deciduous trees have been com- 

 paratively neglected. Eecent experiments have shown that in this 

 quarter also there is abundant room for an extension of our powers 

 of domestication. In one of the London Parks least frequented by 

 the upper ten thousand, that at Battersea, great success has attended 

 the introduction, during the last few years, of half-hardy trees and 

 shrubs, the precaution being taken of protecting their roots during 

 winter by a layer of some substance impervious to frost. The 

 French have paid more attention to the perfect naturalisation of 

 half-hardy plants than we have done : notwithstanding the greater 

 severity of their winter, species are grown by them out of doors 

 which are never seen with us except in greenhouses ; even as far 

 north as Paris, the bamboo, for instance, is frequently met with in 



