_Laboratory exercise._--On variation and heredity among members of a
class in the schoolroom.
_Laboratory exercise._--On construction of curve of variation in
measurements from given plants or animals.
_Laboratory demonstration._--Stained egg cells (_ascaris_) to show
chromosomes.
_Laboratory demonstrations._--To illustrate the part played in plant
or animal breeding by
(_a_) selection.
(_b_) hybridizing.
(_c_) budding and grafting.
_Laboratory demonstration._--From charts to illustrate how human
characteristics may be inherited.