We present a method of lines approximation
of the solution of a particular nonlinear Volterra partial
integro-differential equation. Discretization in space of this
equation leads to a system of stiff integro-differential equations.
In a second step, this system is integrated in time by
the implicit Euler method.
The concept of the logarithmic norm, introduced in the
theory of numerical methods for stiff ordinary differential
equations, plays an important role in the convergence analysis.