appeared shortly after, 1 adopted many precautions which 
should enable me to watch its progress. I procured a very 
delicate thermometer, applied it accurately to the most 
sensible parts of the flower, and protected the bulb, by folds 
of flannel from the influence of the circumambient atmo- 
sphere, and by a paper shade from the rays of the sun. 
Another thermometer was suspended in the stove not far 
from the plant, to give the temperature of the stove. 
* For six days a striking increase of heat took place in the 
flower, attaining its maximum about four o’clock in the after- 
noon, and totally ceasing during the night and early morn- 
ing. The greatest difference between the temperature of the 
flower and the general atmosphere of the stove was eleven 
degrees ; and as in the first blossom which was examined, so 
the central portion of the club of abortive stamens was the 
part which exhibited this heat most powerfully ; next, the 
base of that club; and then the stamens which were 
fertile.” 
Another highly interesting circumstance is connected with 
this beautiful and striking plant: it is comparatively easy 
to observe the mode in which its pollen-tubes penetrate the 
tissue of the stigma. If the pistils be examined after the 
flower has faded, it will be seen that the stigmas are covered 
with a thick layer of pollen, and that a portion of these 
smooth spherical granules of pollen have given birth to 
membranous tubes, of greater or less length, which, pene- 
trating between the utricles which constitute the papilla of 
the stigma, enter, more or less deeply, into the substance 
of this organ. 
It may be asked whether these pollinary tubes are pro- 
longed into the ovules, as is the case in the Orcuipez ; or 
whether they lose themselves in the substance of the stigma? 
And this is a point which still remains in doubt. It is a 
certain fact, that in many ArormpEz, the ovary presents, 
after fertilization, some filaments, which, proceeding from 
the style, do fill up, in part, the cavity ; but these filaments 
may be a prolongation of the conducting tissue as well as of 
the pollen-tubes. 
The organs of vegetation in this plant also possess some 
very curious peculiarities of structure. The geminate pe- 
duncles in the axils of its enormous petioles exhibit, as do 
those petioles and the nerves of the leaves, numerous cylin- 
drical cavities, which, to the naked eye, appear as if coated 
with shining points. When examined under a microscope, 
these points are seen, both by transverse and longitudinal 
section, 
