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placed here, in order to show the relationship of the orchid 
family to the other endogenous ones. Curious among 
the exogenous plants is the horsetail knotweed (Polygonum 
equisetiforme), of southern Europe. Others of curious 
interest are the pitcher-plants (Sarracenia), of the south- 
eastern United States. The pitchers contain a liquid in 
which the insects are drowned, the fluid resulting through 
their decay being absorbed by the pitchers; these struc- 
tures form a part of the leaves and are a modification of 
the petiole. The sundews (Drosera) are also insectivorous 
plants; they secrete a sticky substance from the glandular 
hairs on their leaves, which can digest insects and other 
animal matter. A plant useful as a ground cover in a 
temperate house is Helxine Soletrolit, a member of the 
nettle family. It grows rapidly and soon forms a beautiful 
carpet of green. 
House No. 16. This house is about 28 feet wide and 43 
feet long. Here is a collection of sago palms or cycads; 
others will be found on the south end of the center bench in 
house 10. This family of plants is represented by large 
specimens of Cycas revoluta, from Japan; Cycas circinalis, 
from the Molucca Islands; a single plant of the rare 
Stangeria eriopus, from southern Africa, where it is known 
as the kaffir’s-head; the American genus, Ceratozamzia, 
named on account of the horns on the scales of the cone— 
Ceratozamia mexicana and Ceratozamia Miqueliana, both 
from Mexico, are in the collection; a number of specimens of 
the genus Zamia, including the small Florida coonties; 
the kaffir-bread (Encephalartos), from Africa; Macrozamia 
Moorei, from Australia; and the Mexican genus Dioén. 
The stems and trunks of plants of this family contain much 
starch, which is extracted, in the countries in which they 
grow, by crushing and washing, and passes into commerce 
under the name of sago starch. On the walls are specimens 
of aroid vines. 
House No. 18. This house is about 68 feet long; it 
contains a part of the collection of tree-ferns, specimens of 
