SAPROPHYTES 
177 
Total parasitism is well shown in Cuscuta and Cassytha, 
with their twining stems and absence of chlorophyll and of 
leaves; these are both parasitic upon stems, while Orobanche, 
Lathraea, &c., are total parasites upon roots. A further step 
in the degradation of the vegetative system leads to the very 
remarkable orders Balanophoraceae, Hydnoraceae, and Raf- 
flesiaceae, above mentioned. 
Saprophytes 1 are plants which grow upon decaying 
organic matter and absorb the products of decay. Such 
are most of the Fungi, perhaps a few’ Mosses, &c., and a 
few' flowering plants, e.g. the Orchidaceae Neottia, Epipogon, 
and Corallorhiza, the Triuridaceae, the Burmanniaceae, and 
Bartonia, Monotropa, &c. The prothallus of Ophioglossum 
is also saprophytic. 
It is probable that many plants are more or less sapro- 
phytes in a sense. The complete saprophytes above men- 
tioned have no green tissue at all, for they take in their 
carbon from the soil in the form of complex organic com- 
pounds. These bodies possess potential energy, and 
therefore the absorption of light-energy becomes needless. 
Chlorophyll is thus rendered useless and is no longer pro- 
duced, while at the same time, as there is no absorption of 
carbon dioxide from the air and the elaboration of new 
protoplasm may go on anywhere in the plant, the leaves, 
as in total parasites, are rendered useless also (being needed 
neither for assimilation nor transpiration), and are reduced 
to small scales. Many of these plants, e.g. Monotropa, 
possess a mycorhiza (p. 39), and it is very likely that all 
plants which have this symbiosis (or living together for 
mutual benefit) with the fungus are to some extent sapro- 
phytic, in that they take up more or less of the complex 
products of decay from the soil. 
Insectivorous Plants 2 obtain more or less nourish- 
ment from the dead bodies of small animals captured by 
means of special apparatus. There are about 400 species 
of these plants, belonging to 16 genera, in the orders Dro- 
seraceae (Drosera, Drosophyllum, Dionaea, Aldrovanda, 
&c.), Sarraceniaceae (Sarracenia, Heliamphora, Darling- 
1 Schimper, op. cit . ; Johow in Fringe. Jahrb. xvi, xx. 
2 Darwin, Insectivorous Plants ; Goebel, PJlanzenbiologische Schilder- 
iingen. 
W. 
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