SS ee eee i ae ee ee eee Sie he en ee e 
THE DEVELOPMENT OF THE ASCOCARP OF LEOTIA* 
WiLtitiAM H. BRown 
(WITH FORTY-SEVEN FIGURES) 
The present study is based upon material of Leotia lubrica and 
L. chlorocephala collected at Cold Spring Harbor, Long Island. 
For microscopical study, sections were cut 2 and 3 4 thick and 
stained with either Haidenhain’s iron-alum hematoxylin or 
Flemming’s triple stain. 
Leotia lubrica 
Leotia lubrica grows in damp places among various species of 
mosses. Several ascocarps are often connected together by their 
bases, and sometimes a small one may grow out from the base of 
a mature specimen. 
The age of an ascocarp cannot always be told from its size, 
for one 3 mm. long may be more mature than one about 1 cm. in 
length. The youngest specimens found were about 1.5 mm. long, 
and were nearly conical in shape (fig. 1). When the ascocarp has 
reached a length of about 2 mm., the tip of the cone begins to 
enlarge to form the head (figs. 2, 3); this is about the stage at 
which the hymenium begins to be differentiated. The ascocarp 
soon assumes the mature form (fig. 4), and the further changes 
are largely those of growth. The hymenium now covers the upper 
surface and margin of the head. The upper surface may continue 
to grow until its margin becomes curved in toward the stalk (fig. 5). 
The youngest specimen found was composed largely of densely 
interlacing vegetative hyphae. At the base of the ascocarp there 
was a very large cell (fig. 6) from which a number of large hyphae 
extended upward toward the tip of the ascocarp. This large cell 
was vacuolated and its contents had degenerated, giving it all the 
appearances of an emptied ascogonium. The hyphae arising from 
this cell were empty, as is usually the case in old ascogenous hyphae, 
and so could not be traced with certainty for any great distance. 
« Contribution from the Botanical Laboratory of the Johns Hopkins University, 
no. 17. 
443] [Botanical Gazette, vol. 50 
