The feature, which would add a more robust bookmarking functionality, was discovered by MacRumors. According to the report, the feature is inactive and "hidden" within the latest Mac OS X 10.7 Lion builds.
"Reading List lets you collect webpages and links for you to read later. To add the current page to your Reading List, click Add Page. You can also Shift-click a link to quickly add it to the list. To hide and show Reading List, click the Reading List icon (eyeglasses) in the bookmarks bar," Apple reportedly wrote regarding the feature.
Further details regarding Apple's plans to implement the feature remained unclear, though the report did suggest that Apple may allow syncing between devices. If so, Reading List would compete with popular iOS apps such as Instapaper and ReadItLater.
Earlier this month, details emerged that the next version of Safari on Mac OS X 10.7 Lion will include a do-not-track tool that would allow users to request not to be tracked by websites.
Mac OS X 10.7 is scheduled for a summer release. An updated build of Mac OS X 10.7 Developer Preview 2 was released earlier on Friday. Apple will ""unveil the future of iOS and Mac OS" in June at the Worldwide Developers Conference.
For more information on upcoming changes in Mac OS X Lion, see AppleInsider's in-depth series: Inside Mac OS X 10.7 Lion. Recent features include:
Inside Mac OS X 10.7 Lion: Developer Preview 3 dials down animated tabs
Inside Mac OS X 10.7 Lion: iTunes screen saver controls music playback
Mac OS X 10.7 Lion to add Office file viewing, new text and signature annotation
Mac OS X 10.7 Lion: new multitouch gestures, Dock integration for Exposé, Launchpad, Mission Control
Inside Mac OS X 10.7 Lion: New dictionaries, multiple word views, multitouch lookups