The small island of Inishglora, off the Mullet Peninsula in County Mayo, carries an entry for cross-slabs, the kind of inscribed or carved stone markers associated with early Christian monastic sites, that is built almost entirely on a single passing remark and the persistent silence that followed it.

The trail leads back to H. S. Crawford, who in 1913 noted, almost in parentheses, that on Inishglora there were "several other slabs never described." The phrase is tantalising in its vagueness. Crawford did not describe them himself, apparently, and no subsequent survey has been able to locate any cross-slabs on the island at all. As things stand, none are known to exist. What the 1913 reference actually points to, whether slabs that have since been lost, buried, removed, or simply misidentified, remains unresolved. The island itself has genuine early Christian significance, associated with the sixth-century saint Brendan of Clonfert, and the remains of a small monastic enclosure survive there. That context makes Crawford's aside easy to believe and impossible to verify.

What this record ultimately documents is a gap, an archaeological maybe that has never been closed in either direction. Cross-slabs, when they do survive, are often plain stones bearing an incised cross, modest by later medieval standards but significant as markers of early devotional practice. On Inishglora, the possibility that several such stones once existed and were simply never written down properly is neither confirmed nor dismissed. It remains, more than a century after Crawford's footnote, an open question sitting quietly off the Mayo coast.