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assembled to facilitate the production of a monograph on 
this family now in course of preparation by the Garden in 
cooperation with the Carnegie Institution. In addition to 
the plants in these houses, many hundreds of others are 
located at the propagating houses. Nearly all these 
plants are devoid of leaves, these organs, when present, 
being mostly small and inconspicuous; in the genus Opuntia 
they are usually present on the young growths as awl- 
shaped bodies, while in some few species they are much 
larger and remain for some time; in the genus Pereskia, 
specimens of which will be found in house No. 8, the leaves 
are large and well developed. The stems of the cacti are 
fleshy and assume a great number of forms; in Opuntia 
the stem is composed of joints, either cylindric or broad and 
flattened. In Cereus and related genera the stems are 
angled; in Carnegiea they are thick massive columns with 
many longitudinal ribs; in Echinocactus the plant-bodies 
are but little elongated, or almost globular, while in other 
genera the plant-body is covered with rows of spirally ar- 
ranged projections. The flowers of many cacti are ex- 
quisite in form and color; they are borne on various parts 
of the plant-body, in the turk’s-head cactus on a curiously 
modified portion of the top. 
In house 7 on the north bench and the north part of the 
center bench is the genus Cereus and its many related 
genera, Pachycereus, Cephalocereus, Leptocereus, Acan- 
thocereus, Nyctocereus, Hylocereus, Selenicereus, Harrisia, 
and others. Among these is the old-man cactus, Ce- 
phalocereus senilis. On the west end of the center bench 
and on the side bench opposite is a collection of the genus 
Epiphyllum, often known as Phyllocactus. The broad 
flattened parts of these plants are stems and not leaves, 
the flowers being borne in the notches along their edges. 
The flowers are very showy; many of them beautiful in 
the extreme. On the south side of the center bench are 
plants of the hedgehog cactus, Echinocactus, and also of 
Echinocereus and Echinopsis. On the south bench is a 
