To which package refers mongo@1.13.0 in the version file

Hello, in .meteor/versions the package mongo@1.13.0 ist listet. In older meteor versions it’s mongo@1.3.1.

I thought The Node mongoDB driver is “mongodb”. To what refers this mongo package?

Packages in .meteor/packages are Atmosphere packages, not npm packages.
See: Using Atmosphere Packages | Meteor Guide

These packages are either part of Meteor: github.com/meteor/meteor/tree/master/packages/
or hosted on atmospherejs.com

Now mongo@1.13.0 is the current version from here: meteor/packages/mongo at master · meteor/meteor · GitHub
Which depends on npm-mongo here
Which then bundles the node mongoDB driver via the npm package mongodb: "3.6.10"

Thanks a lot @coagmano. That was very helpful.