The Ormesby Psalter (Bodleian Library MS. Douce 366), is not a bestiary. It is a psalter, a collection of Psalms meant for contemplative reading. The wealthy would commission such manuscripts, and many of them are richly illustrated. Some of them used bestiary themes in their marginal illustrations (the Queen Mary Psalter has most of a bestiary in its margins) or in historiated initials. The Ormesby Psalter has a few beautiful animal illustrations, like this one.
While a knight methodically chops the heads off a multi-headed dragon (perhaps the hydra, or the Beast of the Apocalypse), two rabbits do mock battle with sword and mace, and a dog sleeps peacefully amid the carnage.
Another dog waits patiently for his master to stop having a symbolic conversation with a strange man she met while out walking her hound and squirrel. Quite what is going on here is beyond me, but perhaps the man, with a suggestive sword sticking out of his side and a very large ring, is proposing to the woman that they merge their menagerie in holy matrimony.
The dog looks amused by all this, but probably just wants to get on with the walk.
The illustration I like most is of the unicorn.
Here we have a spirited unicorn, that despite his wound turns to take on the cruel knight who spears him. Perhaps the unicorn will yet bag himself a knight to hang on his trophy wall. The maiden seems distressed, as well she should be, since she got the beast into this mess in the first place. At least she is gesturing to the knight to stop his attack; maybe the unicorn will spare her when he finishes off his attacker.