USNM:PAL
Billingsella perfecta Ulrich & Cooper
USNM PAL142395
USNM:PAL
Billingsella plicatella Walcott
USNM PAL52266A
United States, Wyoming
USNM:PAL
Xenorthis stosei (Bassler)
USNM PAL66164E
USNM:PAL
Billingsella coloradoensis (Shumard)
USNM PAL35213C
USNM:PAL
Billingsella pumpellyi Walcott
USNM PAL52558A
USNM:PAL
Billingsella romingeri (Barrande)
USNM PAL52267D
USNM:PAL
Cymbithyris hami Cooper
USNM PAL116724
USNM:PAL
Billingsella major Walcott
USNM PAL52256A
USNM:PAL
Billingsella texana Bell in Bell & Ellinwood
USNM PAL185523
United States, Texas, Blanco County
USNM:PAL
Billingsella exporrecta (Linnarsson)
USNM PAL52249I
USNM:PAL
Billingsella alata Bell
USNM PAL111888
USNM:PAL
Billingsella perfecta Ulrich & Cooper
USNM PAL91441D
USNM:PAL
Billingsella rhomba Ellinwood
USNM PAL185532
United States, Texas, San Saba County
USNM:PAL
Billingsella coloradoensis (Shumard)
USNM PAL34774B
USNM:PAL
Billingsella texana Bell in Bell & Ellinwood
USNM PAL185520
United States, Texas, Mason-Gillespie County
USNM:PAL
Billingsella perfecta Ulrich & Cooper
USNM PAL91441C E. Kirk
United States, Wyoming
USNM:PAL
Billingsella perfecta Ulrich & Cooper
USNM PAL91441S E. Kirk
United States, Wyoming
USNM:PAL
Billingsella plicatella Walcott
USNM PAL52263L
USNM:PAL
Billingsella plicatella Walcott
USNM PAL52263D
USNM:PAL
Billingsella plicatella Walcott
USNM PAL52266B
United States, Wyoming
USNM:PAL
Billingsella exporrecta (Linnarsson)
USNM PAL52249K
USNM:PAL
Billingsella plicatella Walcott
USNM PAL52263A A. Peale
United States, Montana, Gallatin County
USNM:PAL
Billingsella exporrecta (Linnarsson)
USNM PAL52249A
USNM:PAL
Xenorthis stosei (Bassler)
USNM PAL92836C G. Cooper
United States, Maryland
USNM:PAL
Billingsella striata Walcott
USNM PAL52279A A. Peale
United States, Montana, Madison County
USNM:PAL
Billingsella highlandensis (Walcott)
USNM PAL15355A
USNM:PAL
Billingsella major Walcott
USNM PAL52256B
USNM:PAL
Billingsella perfecta Ulrich & Cooper
USNM PAL91441M
USNM:PAL
Billingsella corrugata Ulrich & Cooper
USNM PAL91442M
USNM:PAL
Billingsella plicatella Walcott
USNM PAL52263E
USNM:PAL
Billingsella corrugata Ulrich & Cooper
USNM PAL91442A
USNM:PAL
Billingsella plicatella Walcott
USNM PAL52263G
USNM:PAL
Billingsella dice Walcott
USNM PAL52248D
United States, Vermont, Franklin County
USNM:PAL
Billingsella plicatella Walcott
USNM PAL52265A
USNM:PAL
Billingsella plicatella Walcott
USNM PAL137090
USNM:PAL
Billingsella coloradoensis (Shumard)
USNM PAL35213B
USNM:PAL
Xenorthis stosei (Bassler)
USNM PAL66164D
USNM:PAL
Billingsella salemensis (Walcott)
USNM PAL17443A
USNM:PAL
Billingsella corrugata Ulrich & Cooper
USNM PAL91442K E. Ulrich
United States, Oklahoma
USNM:PAL
Xenorthis stosei (Bassler)
USNM PAL92836B
USNM:PAL
Billingsella corrugata Ulrich & Cooper
USNM PAL91442H E. Ulrich
United States, Oklahoma
USNM:PAL
Billingsella pumpellyi Walcott
USNM PAL52558 Blackwelder & Willis
China, Shantung
USNM:PAL
Billingsella dice Walcott
USNM PAL52248E
United States, Vermont, Franklin County
USNM:PAL
Billingsella coloradoensis (Shumard)
USNM PAL35213B
United States, Wyoming
USNM:PAL
Billingsella perfecta Ulrich & Cooper
USNM PAL91441I E. Kirk
United States, Wyoming
USNM:PAL
Billingsella texana Bell in Bell & Ellinwood
USNM PAL185518
United States, Texas, Mason-Gillespie County
USNM:PAL
Billingsella coloradoensis notorcadensis (Shumard)
USNM PAL34776B
USNM:PAL
Billingsella marion Walcott
USNM PAL53676B Walcott & Burling
Canada, British Columbia
USNM:PAL
Billingsella pumpellyi Walcott
USNM PAL52558A Blackwelder & Willis
China, Shantung
USNM:PAL
Billingsella anomala Walcott
USNM PAL52233D Curtice
United States, Alabama, Cherokee County
USNM:PAL
Billingsella perfecta Ulrich & Cooper
USNM PAL91441E E. Kirk
United States, Wyoming
USNM:PAL
Billingsella pumpellyi Walcott
USNM PAL96088
USNM:PAL
Billingsella coloradoensis (Shumard)
USNM PAL34771F
USNM:PAL
Billingsella anomala Walcott
USNM PAL52233F Curtice
United States, Alabama, Cherokee County
USNM:PAL
Billingsella highlandensis (Walcott)
USNM PAL15355D
USNM:PAL
Billingsella perfecta pyriformis Bell
USNM PAL111883
United States, Montana
USNM:PAL
Billingsella plicatella Walcott
USNM PAL111887
United States, Montana
USNM:PAL
Xenorthis aequicostellata Ulrich & Cooper
USNM PAL92834A G. Cooper
United States, Maryland
USNM:PAL
Xenorthis stosei (Bassler)
USNM PAL66164
USNM:PAL
Billingsella rhomba Ellinwood
USNM PAL185531
United States, Texas, San Saba County
USNM:PAL
Billingsella coloradoensis (Shumard)
USNM PAL185543
United States, Texas, Mason-Gillespie County
USNM:PAL
Xenorthis stosei (Bassler)
USNM PAL66164E
USNM:PAL
Billingsella radiata Bell
USNM PAL111885
United States, Montana
USNM:PAL
Billingsella lindstromi (Linnarsson)
USNM PAL52259A
USNM:PAL
Billingsella texana Bell in Bell & Ellinwood
USNM PAL185519
United States, Texas, Mason-Gillespie County
USNM:PAL
Billingsella perfecta Ulrich & Cooper
USNM PAL91441H E. Kirk
United States, Wyoming
USNM:PAL
Billingsella plicatella Walcott
USNM PAL52263K A. Peale
United States, Montana, Gallatin County
USNM:PAL
Billingsella coloradoensis (Shumard)
USNM PAL35213E
USNM:PAL
Billingsella coloradoensis (Shumard)
USNM PAL35213A
United States, Wyoming
USNM:PAL
Billingsella origin Walcott
USNM PAL69808
Canada, British Columbia
USNM:PAL
Billingsella dice Walcott
USNM PAL52248B
USNM:PAL
Billingsella saffordi Walcott
USNM PAL52268B Campbell
United States, Tennessee
USNM:PAL
Billingsella corrugata inornata Ellinwood
USNM PAL185536
United States, Texas
USNM:PAL
Billingsella olen Walcott
USNM PAL69711
USNM:PAL
Billingsella major Walcott
USNM PAL52256B J. James
United States, Wisconsin, Sauk County
USNM:PAL
Billingsella plicatella Walcott
USNM PAL52263D
USNM:PAL
Billingsella perfecta Ulrich & Cooper
USNM PAL91441L
USNM:PAL
Billingsella coloradoensis (Shumard)
USNM PAL35213F
United States, Wyoming
USNM:PAL
Billingsella perfecta Ulrich & Cooper
USNM PAL91441K E. Kirk
United States, Wyoming
USNM:PAL
Billingsella plicatella Walcott
USNM PAL52263B A. Peale
United States, Montana, Gallatin County
USNM:PAL
Billingsella coloradoensis (Shumard)
USNM PAL34776C
USNM:PAL
Billingsella corrugata Ulrich & Cooper
USNM PAL91442C
USNM:PAL
Billingsella alata Bell
USNM PAL52266A
USNM:PAL
Billingsella harlanensis Walcott
USNM PAL5225E C. Walcott
United States, Tennessee, Hawkins County
USNM:PAL
Billingsella whitfieldi (Walcott)
USNM PAL24591A
USNM:PAL
Billingsella highlandensis (Walcott)
USNM PAL15355E
USNM:PAL
Billingsella texana Bell in Bell & Ellinwood
USNM PAL185525
United States, Texas, Blanco County
USNM:PAL
Billingsella pumpellyi Walcott
USNM PAL52557 Blackwelder & Willis
China, Shantung
USNM:PAL
Xenorthis jonasae Ulrich & Cooper
USNM PAL92835A G. Cooper
United States, Maryland
USNM:PAL
Billingsella Lochman & Hu
USNM PAL138207
USNM:PAL
Billingsella saffordi Walcott
USNM PAL52268 Campbell
United States, Tennessee
USNM:PAL
Billingsella striata Walcott
USNM PAL52279B
USNM:PAL
Billingsella dice Walcott
USNM PAL52248C
USNM:PAL
Billingsella lindstromi (Linnarsson)
USNM PAL52259D
USNM:PAL
Billingsella coloradoensis (Shumard)
USNM PAL34771E
USNM:PAL
Billingsella dice Walcott
USNM PAL52248E
USNM:PAL
Xenorthis jonasae Ulrich & Cooper
USNM PAL92835F
USNM:PAL
Billingsella perfecta Ulrich & Cooper
USNM PAL91441F E. Kirk
United States, Wyoming
USNM:PAL
Billingsella perfecta Ulrich & Cooper
USNM PAL91441 E. Kirk
United States, Wyoming
USNM:PAL
Billingsella harlanensis Walcott
USNM PAL52252G C. Walcott
United States, Tennessee, Hawkins County