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M I C H A E L L O C K E
did migrate over filters implanted flat in the plane of the cuticle with
the cells upon only one side.
The obvious conclusion that epidermal cells do not migrate when they
can communicate with one another across the millipore filter should be
accepted with caution, since there are other possible explanations. There
is no completely satisfactory control experiment to show that epidermal
cells are not influenced by the nature or texture of the material of the
Fifth
Adult
Fifth
Adult
FIG. 40. A: Diagram showing the position and way in which test strips of filter
or Teflon were inserted into fourth and fifth instar Rhodnius larvae. B : The effect
upon the adult cuticle of separating the epidermis of the integument with a sheet
of Teflon in the fifth instar. The epidermis migrates over the surface and later deposits cuticle. C : The effect upon the adult cuticle of separating the epidermis of
the integument in the fifth instar with a millipore filter. There is no cell migration
and the epidermis remains separated by the filter. D : The effect upon the adult
cuticle of repairing an excision in the fifth instar integument with a millipore filter.
The epidermis migrates over the filter.