The electron velocity distribution function is presented in the energy range 25 eV <E<15 keV during a rocket flight over an active aurora. The electron measurements are compared with optical observations by all-sky cameras and a television system. The most striking feature of the velocity distribution function is a broad plateau produced by downcoming electrons. This plateau is the feature of the electron distribution function that is associated with discrete auroral forms. Plateaus either appear or broaden by extending to higher energies each time a bright form is entered. The plateaus decay by erosion of the highest-velocity portions when the rocket passes either out of an arc or into weak diffuse auroral structures. The high-velocity cutoff of the plateau also fluctuates when small field-aligned rays appear within the arcs. Kilovolt electrons were field aligned during portions of this flight, though such alignment was not as striking as that on previous flights. The field alignment is usually confined to a narrow energy band but extends over a broad range of energies during one interval. Electrons with v<10¿108 cm/s (E=300 eV) are nearly isotropic in pitch angle throughout the flight. Upgoing electrons show almost no pitch angle dependence beyond 120¿, and their fluxes decline smoothly as energy increases, with little or no evidence of a plateau. Preliminary results of numerical integrations, to study bulk properties and stability of the plasma are presented.