I don’t think the leaves are right for toadflax… But if it is toadflax, be careful… Mowing it means that you lose it, as it’s an annual (and not at all weedy), and needs to set seed… I’ve found buckeye caterpillars on toadflax, it’s definitely a keeper… If you ever find out how to kill the bermuda, I know a lot of gardeners who would like to know the secret.

Old field toad flax. http://www.missouriplants.com/Bluealt/Linaria_canadensis_page.html

maybe cowcockle? (Vaccaria hispanica) http://wisplants.uwsp.edu/scripts/detail.asp?spcode=vachis

I wonder if it might be related to corn cockle? http://www.robsplants.com/plants/AgrosGitha

Maybe Toadflax