structural:expansion
The allegorical texts

The siren and the onocentaur, two hybrid creatures, appear as the subject of a single chapter in the Physiologus, as they appear together in the Septuagint translation of the aforementioned Isaiah 13:21–22, and 34:14. They also appear together in some Latin bestiaries of the First Family subgroup called B-Isidore ("B-Is").