https://fwgna.blogspot.com/2015/04/the-heritability-of-shell-morphology-in.html
Freshwater Gastropods of North America: The heritability of shell morphology in Physa h^2 = 0.819!
Freshwater snails, gastropods, evolution, systematics, taxonomy, ecology, invertebrates, rivers, lakes, environment, America
https://fieldguide.mt.gov/speciesDetail.aspx?elcode=IMGASL9130
Tadpole Physa - Montana Field Guide
Montana Field Guide contains a wealth of information about Montana's diverse species.
tadpolephysamontanafieldguide