4 BOTANICAL GAZETTE . [JANUARY 
on growth of the embryos, the influence of different concentrations 
of sugar on growth, the effects induced by certain plant extracts, 
the favorable influence of certain bacteria, and experiments on 
transplanting. In the discussion are treated critically the ideas 
expressed by BERNARD and BuRGEFF with respect to the function 
of the fungus. 
For a clearer understanding of the data that follow, it is desir- 
able to trace briefly the mode of development in the germination 
of seeds of Cattleya and Laelia. For a detailed discussion, 
BERNARD’S paper should be consulted. The embryo is somewhat 
oval-shaped, and is undifferentiated except that the cells at the 
basal region are large, while those at the apical region are smaller. 
This is the meristematic region. At the base is subtended a delicate 
suspensor.. The embryo is inclosed within a transparent integu- 
ment with an opening at the lower end through which the suspensor 
may protrude. The maximum length of the embryo of Caiileya 
or Laelia is about 250u and the width about 75y. 
Germination consists, first, in an enlargement of the embryo in 
a transverse direction until a small spherule stage is reached. 
Accompanying this development there is the formation of chloro- 
phyll, generally more pronounced in the meristem region. The 
embryo when it ruptures the integument has a width of about 175u 
and a length of about 2704. At the time of rupturing the integu- 
ment, absorbing hairs begin to grow out from the epidermis. Sub- 
sequent development consists in a further enlargement of the 
embryo, other absorbing hairs begin to develop near the basal 
region, and there is attained a large spherule or top-shaped 
structure characterized by a marked depression at the upper 
surface. Following this there appears in the middle of the depres- 
sion the first leaf point, which subsequently develops into the first 
leaf. During this period there is a continued increase in the 
diameter of the embryo, so that a disklike structure is formed which 
has been termed by BERNARD the protocorm. At the meristematic 
region a second and a third leaf may unfold, elongation may occur, 
and a distinct stem is apparent. The first root may arise either 
from the protocorm or from the stem below the second or the third 
leaf. The period required for these developments is generally 
