50 FERNS AS DECORATIVE OBJECTS. 



have no effect in deteriorating the air, and that its original con- 

 stitution will remain unclianged. As the most important func- 

 tion of vegetable 'life is the decomposition of carbonic acid gas, 

 and the assimilation of carbon under solar influence, the source 

 of the latter, and other aliments which plants derive from the 

 air, will be present in the usual proportions. Nevertheless the 

 plants may not be able to assimilate their due proportion of these 

 elements, for the sluggish motion of the air in a hot-Iiouse is so 

 different from the natural atmosphere, which is always in motion, 

 more or less rapid, both horizontally and vertically, that the 

 plants may not be able to appropriate their due share of atmos- 

 pheric food, the air not coming fast enough in contact with the 

 leaves, and other surfaces of absorption. The advantages to 

 vegetation of brisk motion in the air, therefore, will be obvious. 



XV. — Fer?is as Decorative Objects. By Thomas Moore, F.B.S., 

 Curator of the Physic Garden of the Worshipful Society of 

 Apothecaries, Chelsea. 



(Communicated March, 1849.) 



"Within the last few years the^ taste or fancy for Ferns appears 

 to have been on the increase ; and this has latterly become very 

 apparent, as in some degree is evidenced by their appearance in 

 profusion at public exhibitions of plants. It has been thought 

 that a few hints might be thrown out of such a nature as to help 

 forward and more widely extend this class of cultivation, so 

 peculiarly deserving of attention. Without claiming any pe- 

 culiar fitness for the task, I have ventured to attempt its exe- 

 cution, in the hope of being able to supply some instruction to 

 those who really need it. To tliose who are already well versed 

 in the art of culture, and to those also who understand Ferns, the 

 hints which follow are not addressed. 



Viewed as objects of decoration. Ferns may be conveniently 

 disposed into two principal groups, namely, 



I. Those wliich are suitable for cutting as an addition to 

 bouquets, both large and small. 



II. Those in whicli the entire plant, well cultivated, may be 

 specially employed for purposes of ornament. 



The latter of these two groups evidently includes the greater 

 number of the species belonging to the former, and may be com- 

 posed of individual kinds proper for cultivation in pots or vases, 

 as well as of those which may be managed in a semi-natural way, 

 attached to rocks or the stumps of trees ; most of the species 

 being suitable for either of these modes of culture. 



I. For hand-bouquets it is obviously the smaller-growing 



