The phrase 'the starter proper' is correct grammar for saying 'directly mounted to the starter'. I guess you missed English class the day they explained that, huh?
In all seriousness, the starter solenoid on a 97 does double duty. It engages the drive into the flywheel, and it also closes the main high-current connection to the starter windings. This is different than the older XJ's with the fender mounted Ford-type starter solenoid/relay.
1992 XJ 2" lift -- RIP
2000 XJ 3" lift -- Australian Ford Big Brakes up front, rock rails, ZJ rear discs (with WORKING parking brake), C4x4 rear bumper/tire carrier, Hella H4 headlights, IPF driving lights, OEM skid plates, OME springs/shocks, JKS LCA's, JKS Sway Bar links.