76 A LABORATORY MANUAL OF BOTANY 
of the knowledge since obtained in the laboratory. Much 
that is new will now be observed. It is not essential to 
learn the names of all the Algz found, but those studied 
in the laboratory should, if possible, be located in their 
natural growing places. 
If abundant representatives of the Alge are not to be 
found in the time allotted to an exercise, it may be possible 
for different students to secure for the laboratory a large 
number of forms that may then be observed by all. If some 
herbarium specimens of Alge from the sea may be had, they 
will help to give an idea of the varied forms, structures, and 
colors to be found in the group. 
