PLATE I. 



(The figures are natural size.) 



Fig. I. Lymncea preblei Dall. The reflected margin of the aperture below 

 the umbilicus is somewhat broken. See p. 70. 



2. A younger specimen of the same species from behind. 



3. Lymncea randolfhi F. C. Baker; p. 71. 



4. The same species, another specimen, from behind ; p. 71.' 



(154) 



