Section 81. All laws relative to attachments of real estate and leasehold estates on mesne process shall apply to registered land, except that the duties required to be performed by the register of deeds shall be performed by the assistant recorder for the registry district where the land lies, who, in lieu of recording, shall register the facts required to be recorded, and for that purpose shall keep books similar to those required to be kept for attachments by registers of deeds, and the fees for registering attachments shall be the same as for recording them.