U. S. NATIONAL MUSEUM 



PROCEEDINGS. VOL. 86 PLATE 12 



1, Operculznoidei prenumm-ilitijormis, new species, Guayabal formation, Poza Rica Well no. S ne ir CVintzintla, \ era- 

 cruz; 2, 0. prenummnlitiformis, Guayabal formation, collection E. Gevaerts no. 551, Zanatepec, Veracruz; 3, 

 OpercuHnoides sp. B, Guayabal formation, near Tantoyuca, Veracruz, collection H. Rankin no. 277, Tantoyuca 

 region; 4, O. ocalanus (Cushman) minor, new variety, Guayabal formation, collection P. von Schumacher no. 

 2S89, east of Tempoal, Veracruz; 5, 0. ocalanus (Cushman), Tantoyuca, Jackson Eocene, collection K. Goldschmid 

 Pit no. 283, southeast of Tempoal; 6, O. vicksburgensis Vaughan and Cole, Alazan formation, collection E. Gevaerts 

 no. 292, southern Miahuapara, Veracruz: 7, O. jenn\i, new species, Guayabal formation, collection H. Meyer no. 

 1477, Santa Clara, southeast of Tantoyuca. X15. 



