BULLETIN 
TORREY BOTANICAL CLUB. 
An Examination of the Seeds of some Native Orchids. 
By CARLTON C. CuRrTISS. 
(PLaATEs CL.-CLII.) 
During the past year some research has been made, at the 
Suggestion of Dr. Britton, on the seeds of the North American : 
Orchids to determine their structure and to note what additional 
characters of classification and relationship the seeds themselves 
might afford. 
The seeds are membranous, rather elongated capsules, loosely 
embracing an elliptical, ovate or pyriform nucellus. In organiza- 
tion they indicate a low type of flowering plant. The nucellus is 
composed of a large number of polyhedral cells, which are filled 
with a granular, amber-colored mass, imbedded in which is a great 
abundance of oily matter. The embryo is exalbuminous, and no 
cotyledon and radicle are formed. The Orchid seeds, therefore, 
are of interest as furnishing an example of the arrested stage of 
embryonic development. With germination the cells of the nucel- 
lus divide, and eventually form tuber-like buds that ultimately 
Sive rise to the plant. In this peculiarity the Orchid resembles 
many saprophytes. Especially in the structure and outward ap- 
pearance of its seed does it closely resemble those of several 
Ericacee, particularly Monotropa. The nucellus is generally an 
excellent illustration of the geometrical arrangement of cells in 
vegetable growth. Two or more confocal periclines are associated 
with a usually larger number of orthogonal hyperbolic trajectories. 
See Pogonia ophioglossoides (and fig. 17, Plate CLI.). 
