(76 ) 
in size. I would therefore emphasize my remarks of last 
year in regard to the crowded condition of the conservatories, 
and make a request for more houses for the accommoda- 
tion of the collections. As there are 7,038 species already, 
it may be seen that a space capacity for 11,200 plants will 
not accommodate two individuals of each species, and as 
stated above, this is the lowest number permissible to safe- 
guard the integrity of the collections. At the propagating 
houses there are now a considerable number of plants await- 
ing transferral; these cannot long be accommodated there, 
as the space is needed for purely experimental and cultural 
operations. 
At present a number of collections of small plants are being 
grown in the large houses at the conservatories, more suitable 
accommodations not being at present available. Such plants 
require for their best culture special conditions which it is 
difficult if not impossible to provide adequately in their pres- 
ent quarters. ‘To attempt to create the humid and hot con- 
ditions required for these plants in large houses with great 
unoccupied areas above the plants greatly adds to the cost of 
maintenance. What is needed for such collections is houses 
of low construction, where the space to be controlled as to 
humidity and heat need be but one half or one third as great 
as in the large houses; such houses also do not furnish op- 
portunities for draughts, which are very inimical to certain 
plants of a tropical habitat. Houses of this character are, of 
course, of much cheaper construction than those which go to 
make up the conservatory range. 
As examples of collections which could be better and more 
economically grown in this style of house, I would refer to 
the tropical ferns in house no. 10, the orchids in houses nos. 
12 and 15, the pitcher-plants, aroids and bromeliads in house 
no. 2, and the greater part of the contents of house no. 3. If 
other quarters could be provided for the contents of these 
houses, a considerable area would become available for the 
larger plants which can be more readily grown in such houses 
as form the conservatory range. 
