where the complete specification includes matter not included in the (c) provisional specification— (i) allow the application to be proceeded with in so far as the matter included both in the provisional and in the complete specification is concerned; and (ii) allow an application for the additional matter included in the complete specification to be made and authorize the application for such additional matter, if lodged at the Patent Office within such period as he may determine, to be dated with the date on which the complete specification was lodged at the Patent Office. (2) If in the case of a Convention application it is found that the matter claimed is not substantially the same as that claimed in the application made in the Convention country in question, the Registrar may, subject to subsection (6) of section nine— (a) refuse to accept the application until it has been amended to his satisfaction; or (b) with the consent of the applicant, treat the application as an application which is not a Convention application. (3) If in the case of a Convention application it is found that the specification lodged in Zimbabwe includes matter not included in the specification lodged in the Convention country, the Registrar may— (a) allow the application to be proceeded with in so far as the matter included in both the Convention country and the Zimbabwe specifications is concerned; and (b) allow an application for the additional matter to be made and authorize such application, if lodged at the Patent Office within such period as he may determine, to be dated with the date on which the Zimbabwe specification was lodged at the Patent Office. (4) An appeal shall lie from any decision of the Registrar under subsection (1), (2) or (3). 15 Lapsing of applications (1) If a complete specification is not accepted within eighteen months from the date of lodging of the complete specification, the application to which that specification relates shall lapse unless— (a) an appeal has been lodged in respect of the application and has not been determined or abandoned; or (b) the time within which an appeal in respect of the application may be lodged has not expired; or (c) the delay in accepting the specification was not due to any neglect or default on the part of the applicant: Provided that if, within twenty-one months from the date of the lodging of the complete specification, the applicant, by notice accompanied by the prescribed fee, so requires, the said period of eighteen months shall be extended to such period, not exceeding twenty-one months from the date of the lodging of the complete specification, as may be specified in that notice. (2) If, at the expiration of the period allowed under subsection (1), an appeal to the Tribunal is pending under any of this Act in respect of the application or, in the case of an application for a patent of addition, either in respect of that application or in respect of the application for the patent for the main invention, or the time within which such an appeal could be brought in accordance with Part X, apart from any future extension of time thereunder, has expired, then— (a) where such an appeal is pending or is brought within the time aforesaid or before the expiration of any extension of that time granted, in the case of the first extension, on an application made within that time or, in the case of a subsequent extension, on an application made before the expiration of the last previous extension, the said period shall be extended until such date as the Tribunal may determine; (b) where no such appeal is pending or is so brought, the said period shall