Botany and Zoology. 155 
likely to answer as well in fungi of which almost no definite fossil 
remains exist. W. G. F, 
5. Beitrdge zur Entwickelungsgeschichte der Flechten, Part II. 
Ueber die Bedeutung der Hymenialgonidien ; by Dr, E. Srant. 
Leipsic,, 1877. 8°.—An admirable essay, excellently planned, 
and beautifully written. In the first part of this work whic 
already been noticed in the Journal, Stahl gave an account of the 
sexual organs of lichens. In the present, he considers the signifi- 
cation of the hymenial gonidia of course in its bearings on the 
menial gonidia are derived from the thalline gonidia and present 
a different aspect simply from their different surround 
the spores are Sacheused some the nial gonidia are 
ways dischar ith them. the res germinate, thei 
hyphe fasten themselves upon the gonidia which then increase 
more rapidly tha re. In from four to five months Stahl suc- 
ceeded in raising n rithecia and spores by his culture of the 
y producing the lichen-fruit in his cultures, Stahl removes this 
o e 
notice the statement in the number of Just’s Jahresbericht that 
