254 MESOZOIC AND CENOZOIC INVERTEBRATES. 



MIOCENE SPECIES. 



Helix (Aglaia) fidelis (Gray) White. 



Bull. U. S. Geol. Surv. No. 18, p. 14, pi. iii, figs. 1-3. Mus. No. 13400. 

 HeUx (Monodon) Dallii Stearns (Ms.). 



Bull. U. S. Geol. Surv. No, 18, pp. 14, 15, pi. iii, figs. 4-6. Mus. No. 13401. 



Helix (Patula) perspectiva (Say) White. 



Bull. U. S. Geol. Surv. No. 18, p. 14, pi. iii, fig. 7. Mus. No. 13402. 

 Gonostoma Yatesii (Cooper) White. 



Bull. U. S. Geol. Surv. No. 18, p. 16. pi. iii, figs. 8-12. Mus. No. 13403. 

 Ostrea subfalcata (Conrad) Heilprin. 



Rev. Foss. Ostreidie N. A., p. 313, pi. xlviii, figs. 1-3. Mus. No. 1668. 

 Unio condoni White. 



Bull. U. S. Geol. Surv. No. 18, pp. 13, 14, pi. ii, figs. 1-3. Mus. No. 13404. 



POST-TERTIARY AND TERTIARY SPECIES OF DOUBTFUL AGE. 



Ostrea lurida (Carpenter) Heilprin. 



Post-Pliocene Rev. Foss. Ostreidae N. A., p. 316, pi. Ixii, figs. 3 and 4. Mue. No. 

 18614. 



