10 MISSOURI BOTANICAL GARDEN BULLETIN 
variety of aroids and other similar plants. To the north 
of the walk are four alcoves, provided primarily for the dis- 
play of orchids. Indeed, the whole house serves as a setting 
for the floral displays which are to be maintained in these 
alcoves throughout the year. The construction of this house 
necessitated placing heating pipes in a trench under the 
walk, but the center of the walk is a continuous slab of 
concrete, so that no discomfort will be occasioned by the 
heat which arises from below. 
Bromeliad House.—This house opens from the west end 
of the aroid house and leads into the ericaceous house. 
single straight walk leads directly to the exit at the north 
end, which during the summer will provide an easy and 
natural way to the arboretum. Owing to the fact that many 
of the bromeliads are epiphytic in habit, they will, for the 
most part, be established on old tree trunks or planted in 
baskets. The ground will be covered by dracaenas, pan- 
danus, crotons, and similar plants. Near the partition at 
the north end a small pergola is to be constructed, upon 
which will be grown the large vanilla plant that for so many 
years has been an object of interest in the old range. While 
the vanilla is an orchid, it requires the same conditions as 
the bromeliads, and hence finds its natural place here. 
Ericaceous House.—Since most plants of the ericaceous 
family will not thrive in any but an acid soil, peat, leaf 
mold, and similar constituents have been especially provided 
in which to establish the plants to be grown in this house. 
Rhododendrons, azaleas, heather, and other Ericaceae will 
be found here, and it is also probable that the fine collec- 
tion of camellias, now being accumulated by the Garden, 
will finally be placed in this house. 
Growing Houses——The houses mentioned above consti- 
tute those which will be open to the general public. The re- 
maining houses will be devoted primarily to the growing of 
orchids, a group of plants which requires very special and 
varied treatment. Large additions have been made to the 
Garden collection of orchids, both by purchase and gift, and 
for the first time conditions are provided which will insure 
their being cared for in a way to bring about satisfactory 
results. A few of the houses will be devoted to the growing 
of water-lilies for outdoor displays, as well as to the propaga- 
tion and care of tropical material. Many plants require a 
resting period under conditions which cannot possibly be 
given in a display house, and there has long been felt the 
