What is Apatosaurus for?

Apatosaurus is a web app for creating, editing, visualizing, and analyzing a digital critical apparatus.


Right now, using Apatosaurus for the creation of a collation from scratch is possible, even straightforward, but it is underdeveloped compared to the other three features that this web app offers. For now, the recommended way of producing digital collation data for more than a few manuscripts is to use the ITSEE Collation Editor. Then, output of the Collation Editor can be imported into Apatosaurus. For researchers without the direct support of ITSEE or INTF, however, moving from transcription to collation can be very challenging. For help bridging this gap, see Criticus.

If you plan to collate only a few textual witnesses, however, then you will save a lot of time and anguish by doing it directly in Apatosaurus.


Once you have a TEI formatted collation file (whether imported or built from scratch using Apatosaurus), you will inevitably need to make edits. These might be corrected transcriptions, or perhaps the addition of patristic and versional evidence.

Apatosaurus provides a safe and comprehensive interface for editing any bit of information from section names to local stemma edges. For changes related to readings, a history of changes is kept so that you can roll back to a previous state.


Apatosaurus uses TEI for interoperability with other tools such as the ITSEE Collation Editor and the open-cbgm. The move of some toward a recognized standard is good for all of us in the field. TEI as an XML specification—while it is technically human-readable—is not meant to be read directly as a normal way of browsing the data.

Apatosaurus visualizes the collation data as a digital critical apparatus while taking advantage of the platform. At first glance, the collation data is laid out in a way that should be familiar to most New Testament textual researchers, namely, it echoes the layout of the Editio Critica Maior (ECM) volumes, albeit in a marginally clearer way. Yet there are additional features only possible in a digital format. For example, hovering the cursor over the basetext words will cause the collation units to be highlighted and the corresponding correlation unit buttons to be indicated. There are also helpful popups over textual witnesses that give additional information such as the date.

There are many additional features related to visualization and exploration in the works. It is a conviction of this project that a digital critical apparatus not be limited by the expectations set by print apparatuses, yet we must begin somewhere. Apatosaurus begins with parity, and then some.


For the first time, a public platform and user interface for an implementation of the Coherence-Based Genealogical Method (CBGM) is available to users for use with their own collation data.

Apatosaurus includes a complete interface for the open-cbgm, developed by Joey McCollum, which is a full and alternative implementation of the CBGM. Read more.

Other analysis tools are planned, such as the tool built into Criticus for listing agreements or disagreements between any number of manuscripts.

Side note about this beta testing period

This web app is in beta testing as of late February 2023. It is being launched with key features in place, but others are underway. Your patience is appreciated during this initial launch. You can expect ongoing styling and feature updates to continue.