The place of origin of coronal mass ejections (CMEs) are streamer belts with a neutral line (NL) and streamer belts without a NL. In some months during 1985--1987, up to 80--90% of the total number of CMEs were produced near streamer belts with a NL. As one approaches maximum solar activity, along with an increase in the number of CMEs, the proportion of CMEs places of origin lie near streamers without a NL is as high as 80%. Because of the inaccuracy in determining the longitude, some CMEs can be referred to both categories. Then the CMEs whose places of origin can be associated solely with streamers without NL will make up 20--25%. Transformation processes of streamer belts with NL and without NL and also processes of disappearance and formation of streamer belts without NL are likely to be an important factor contributing to an enhancement of CME generation. By considering six selected events, it is shown that whether the streamer decays or does not decay with the CME passage depends on the position of the streamer relative to the CME span on the limb.¿ 1997 American Geophysical Union