FISHER: SEED DEVELOPMENT IN THE GENUS PEPEROMIA 145 
and which is usually almost spherical in shape except for the 
depression in the micropylar side occupied by the undifferentiated 
embryo. The nucleus of each cell of the endosperm usually con- 
tains several nucleoli, the number observed varying from one to 
six. 
After the male nucleus has fused with the nucleus of the egg, 
the development of the embryo begins. The fertilized egg divides 
to a two-celled embryo by a wall longitudinal to the nucellus 
(Fic. 15). The cells of the embryo continue to multiply until, in 
the apparently mature seed, there are about twenty cells in a 
median longitudinal section. The mature embryo shows no dif- 
ferentiation externally in any way except that it is somewhat 
flattened on the micropylar side. No suspensor is formed, and 
there is no indication of cotyledons or other organs (FIG. 16). 
PEPEROMIA VERTICILLATA A. Dietr. 
Peperomia verticillata A. Dietr., as used by C. de Candolle (9), 
is listed in the Index Kewensis as P. pulchella A. Dietr., while the 
name P. verticillata A. Dietr. is given as a synonym. 
Part of the material for the study of this species was collected 
near Cinchona, Jamaica, where the plants grew on rocks and trees, 
at an elevation of 5,000 feet. But most of the material was 
collected in the greenhouse of The Johns Hopkins University 
from two plants which had been brought from Jamaica. 
The flower-spikes of P. verticillata average fully three times 
as long as those of P. reflexa, with a range of two to nine centimeters 
in length. They are much less fleshy, and this condition, together 
with other characters of the plant, indicates that it is less strongly 
xerophytic in structure than the species first considered. The 
flowers, which are very similar to those of P. refleva, are not nearly 
So closely crowded on the mature spike, but are loosely scattered 
along the axis. The bracts, trichomes, and oil-cells of the in- 
florescence axis resemble those of the former species. In this 
species the starch grains are strikingly abundant in the bracts. 
The development of the stamen and pollen showed no essential 
difference from that of the former species, although the tapetal 
cells were larger and more conspicuous here (FIG. 19). 
The development of the carpel and ovule, from the differentia- 
