First results concerning the HST-Hα imaging of M1-67 are found in Grosdidier et al. (1998). With the étalon of the Université Laval (Québec), we have obtained complementary Fabry-Pérot Hα data using CFHT-OSIS (August 1996, seeing ≃ 0′′.6, FSR ≃ 392 km s−1, 5.9 kms−1 velocity sampling, see Figure 1). From these data, M1-67 appears more-or-less as a spherical shell seen almost exactly along its direction of rapid spatial motion in the ISM (Moffat et al. 1982). The radial velocity of the center of expansion is rv 137kms−1 (Sirianni et al. 1998). Instead of appearing as a nice hollow-type shell projected on the sky, we probably see the cap of the bow-shock nearly straight on from behind. The far side is greatly intensity-enhanced compared to the near side, probably as a result of raming with the ISM. This was already claimed by Solf & Carsenty (1982). The bright bullets (see Grosdidier et al. 1998) are possibly, after all, Rayleigh-Taylor instabilities seen along the line of sight at or near the bow-shock head, as they slightly ‘fall’ back towards the star. More details will be found in Grosdidier et al. (1999 in preparation).