Do you have any reference where he comments on there being two creation accounts and that it show they should be interpreted allegorically??
I originally heard it on a TV programme during the BBCc Darwin celebrations.
Here's a bit which acknowledges double creation
(19)
Why the creation of animals and flying creatures is mentioned a second time, when the account of their creation had already been given in the history of the six days? (Genesis 2:19). Perhaps those things which were created in the six days were incorporeal angels, indicated under these symbolical expressions, being the appearances of terrestrial and flying animals, but now they were produced in reality, being the copies of what had been created before, images perceptible by the outward senses of invisible models.
Here he acknowledges that there are two stories, the former he calls 'the history of the six days'
He also argues against the 6 days being 6 days
II. (2) "And on the sixth day God finished his work which he had made."
It would be a sign of great simplicity to think that the world was created in six days, or indeed at all in time; because all time is only the space of days and nights, and these things the motion of the sun as he passes over the earth and under the earth does necessarily make. But the sun is a portion of heaven, so that one must confess that time is a thing posterior to the world. Therefore it would be correctly said that the world was not created in time, but that time had its existence in consequence of the world. For it is the motion of the heaven that has displayed the nature of time.
Philo
I'll have a more thorough look tomorrow for more relevant parts
This site says
http://biologos.org/blog/israels-two-creation-stories-part-1;
For example, the ancient Jewish interpreter Philo of Alexandria (20 BC to AD 50) understood Genesis 1 and 2 to be contradictory. This was not a problem for Philo, however. Rather, it signaled to him that the two stories were not meant to be understood historically. God meant them to be understood as pointing to realities deeper than the merely historical.