Lectionary 1637, or ℓ 1637 in the Gregory-Aland numbering, is a Greek manuscript of the New Testament on parchment leaves, dated paleographically to the 9th century.
[1] It is written in Greek Uncial letters on 144 leaves (30 by 26 cm), 2 columns per page.
The codex contains some Lessons from the four Gospels lectionary (Evangelistarium).
The upper text is written in a minuscule hand.
The codex now is located in the University of Michigan (MS. 37) in Ann Arbor.