Various interstellar positron spectra have been re-estimated after taking into account the anomalous solar modulation. Of the spectra, it is found that the one derived from Rockstroh and Webber (1978) is most consistent with the description based on the usual 'leaky-box' model. Further, it is shown that an electron injection spectrum with a single power law cannot explain the primary electron spectrum satisfactorily. Finally, it is proposed that the usual 'leaky-box' model can account for the mean behaviour of interstellar positrons and electrons in a cosmic-ray containment volume whose Galactic scale height and width around us are 0.5-1 kpc and 2-3 kpc respectively.