I'm expecting the answer "Cabbage" but I'm a bit curious. Usually Cabbages have dark tips to the fore wings. And of course, spots. Is there any chance this is one of the more unusual (for the GTA) Whites?
Background:
Seen at the Rattray Marsh in the wooded area on April 20 2016. As shown in second photo, landed on Garlic Mustard.
I was unable to get a photo of the underwings before it flew out of range.
I've posted it to eButterfly and hope to get a reply from there if anyone checks the "species" reports but I'm not sure if they have a volunteer who can help with that or not.
[attachment=1:2vekn9mx]WhiteButterflyRattrayMarshMississaugaONCanadaApril202016Smaller.jpg[/attachment:2vekn9mx]
[attachment=0:2vekn9mx]WhiteButterflyGarlicMustardRattrayMarshMississaugaONCanadaApril202016Smaller.jpg[/attachment:2vekn9mx]
Note the shadow across the photo including the wings. That's not a dark band on the butterfly.
Any advice would be appreciated! I keep taking photos of White butterflies, but so far have only found Cabbages.