The shrew is a mouse that is like a spider because of its venomous bite.

The mygale or migale in Liber de natura rerum, the encyclopedia by Thomas of Cantimpré, has a vague description, but it is in the quadruped section and is said to be poisonous. The Latin word mygale (from the Greek mugalée) means shrew, field mouse or ferret. The names mygale and migale are used for the ferret in the De proprietatibus rerum of Bartholomaeus Anglicus.

This animal signifies the hypocrites and the malicious, of which their weakness, as a wise man says, lies no less daring, when their strength may be present. [Thomas of Cantimpré]