366 : CONCLUSION. (Cuar. XVIII. 
Dr. Mellichamp and Dr. Canby, there can scarcely be a doubt 
that Sarracenia and Darlingtonia may be added to this class, 
though the fact can hardly be considered as yet fully proved. 
[A. Schimper, in an interesting paper,* gives evidence that 
the products of decay are absorbed by the pitchers of Sarra- 
cenia purpurea.t In the epidermic cells at the base of the 
pitcher the changes produced by the presence of decaying 
animal matter are strikingly evident, and bear a strong 
resemblance to the process of aggregation as seen in Drosera. 
The cell-sap is rich in tannin (as in Drosera), and when 
aggregation takes place the single vacuole containing the 
cell-sap is replaced by several highly refractive drops. The 
process resembles in fact the division and concentration of 
the vacuole as described by De Vries (see footnote, p. 35). 
Schimper supposes that the cell-sap gives up to the proto- 
plasm part of its water, and he describes the concentrated, 
tannin-containing drops which are thus formed, as lying in 
the swollen watery protoplasm which now takes up more 
space than in the unstimulated condition. Schimper’s paper 
also contains a good general description of the pitchers of 
Sarracenia.—F’. D. | 
There is a third class of plants which feed, as is now . 
generally admitted, on the products of the decay of vegetable 
matter, such as the bird’s-nest orchis (Neottia), &c.t Lastly, 
* [“ Notizen über Insectfressende 
Pflanzen,” ‘Bot. Zeitung, 1882, p. 
225. 
+ [In the ‘Quarterly Journal of 
Science and Art,’ 1829, vol. ii. p. 290, 
Burnett (as Mr. Thiselton Dyer 
points out to me) wrote as follows: 
“Sarracenia, if kept from the access 
of flies, are said to be less flourishing 
in their growth than when each 
pouch is truly a sarcophagus.” 
According to Faivre (‘Comptes ren- 
dus,’ vol. Ixxxiii. 1876, p. 1155) both 
Nepenthes and Sarracenia flourish 
better when their pitchers are sup- 
plied with water, and Wiesner states 
that Sarracenia can be kept fresh for 
months without watering the roots 
if the pitchers are well supplied. 
(‘Elemente der Anat. und Phys. der 
Pflanzen, 2nd Edit. 1885, p. 226).— 
F. D.] . 
t [Dischidia Rafflesiana, Wall., is 
sometimes doubtfully mentioned as 
an insectivorous plant. The re- 
searches of Treub (¢ Annales du Jardin 
botanique de Buitenzorg, vol. iii.1885, 
p. 13) show that this is not the case. 
Dischidia grows as a climbing epi- 
phyte on trees, and bears clusters of 
modified leaves or pitchers. They 
are of interest morphologically be- 
cause it is the inside of the pitcher 
which corresponds to the lower sur- 
face of the leaf, so that, the pitchers 
are involutions or pouchings of the 
leaf from the lower instead of from 
the upper surface as in Nepenthes, 
Sarracenia and Cephalotus (see Dick- 
son, ‘Journal of Botany,’ 1881, p. 
133). The pitchers of Dischidia are 
covered, both inside and out, with a 
waxy coating which is heaped up in 
a curious manner round the stomata, 
