Fig. 2.

(A) Mulberry Grove Pond in residential area in east-central Moab. (B) Muddy bank of pond, showing several specimens of G. humilis. (C) Shallow, flat-bottomed dish containing mud from pond, in which lab-reared populations of G. humilis were grown. (D) Shell of G. humilis. The largest snails we observed were approximately 11 mm in shell length. (E) Cercaria of H. americana. Note the presence of eyespots, an unusual feature for mammalian schistosomes. Scale bar =80 μm. (F) Egg of H. americana. Note lack of a spine, and the miracidium within. Scale bar =30 μm. (G) Miracidium of H. americana. Scale bar = 50 μm.