Figs. 
Figs. 
Figs. 
Fig. 
Figs. 
Figs. 
Figs. 
Figs. 
Figs. 
Figs. 
29 and 30 
31 and 32 
33 and 34 
36 and 37 
38 to 41 
38 to 40 
41 
42 to 44 
45 to 48 
45 and 46 
47 and 48 
49 to 54 
55 and 56 
‘te 
HEeLCIONOPSIS(STRIATA. WITICH s sstnicieieiclelesieeiee ie eine teehee nike: heeieceaie eae Seer te 
Profile and dorsal views of a gutta percha cast of a natural mold of the exterior 
in the base of a bryozoan. Richmond group, Marion county, Kentucky. 
SCENELLA. RADIALIS (U.and Scat eeeiet eb ea ase ees ak ore er een eiee iia sie 
Two views of the type of this species. The specimen is a cast of the interior. 
Trenton group, St. Paul, Minnesota. Geological and Natural History Survey 
of Minnesota, Museum Register No. 5535. 
SCENELLA)PELOELENSIS, |W). ANG Sack dose, aheceainysni beter Seid els;seieose lee ee espa 
Two views of an internal cast preserving muscularimprints. Stones River group, 
Beloit, Wisconsin. Collection of the University of Wisconsin. 
SCENELLA SUPERBA’ Billlinesap ay. Sn Voltas a tlertcptttonteistelctas cielalbloraeiarer aya alefelviietelole) sieter= 
Profile view of a specimen of the average size and proportions. Stones River 
group, Cannon Falls, Minnesota. 
SCENEEE A APEINTS “Ui tand) SAcied ee 0 AE BIPARTISAN ae fee eberoieereicic= civie ov 
Two views ot a nearly perfect example of the typical form of this species. Be- 
sides the transverse wrinkles shown in the figures, the specimen preserves 
obscure remains of very fine radiating and concentric lines. Black River 
group, Goodhue county, Minnesota. 
SCUNEDUANOOMPRESSALUMand'S S05. RNS EL Ree UE. es ets ee 
Three views of a cast of the interior, the compressed form slightly exaggerated by 
pressure. The second outline shown on two of the figures is intended to show 
the probable original dimensions of the specimen. 
Portion of external surface, obtained from a gutta percha impression of a natural 
mold, x3. 
STEN OMG AS TEN GH ORNS 5 WUT CI setstaretol elols avetetalsynicisisie ales) Ss(sleipae fap aesetarstoleibial</statelaisis’s 
Profile and dorsal views of an average example, and part of its surface, x3. Tren- 
ton group, Mercer county, Kentucky. 
PAL 20 AC Mae ACEO MOIS | Us AIG) Sis. scsps tyejn ais S.5) ve eye yoiny a) ovepn nie Capes 9) ain) se ea=pe yee w1e ae ee 
Two views of a small but well preserved example. Ctenodonta bed of the Black 
River group, Goodhue county, Minnesota. : 
Similar views of a cast of the interior from the Vanuxemia bed of the Stones 
River group at Minneapolis. Geological and Natural History Survey of Minne- 
sota, Museum Register No. 5104. 
RIVAL. GHRASI GE) pWaSCONSENEINS By sUls ATG i. ot. ous trieiossieloie bye Seis in a Spaibheieieteicle sieie ic ciel eiote coke 
Two views each of three casts of the interior showing the variable nature of this 
shell. Stones River group, Beloit, Wisconsin. Collections of the University of 
Wisconsin, and of E. O. Ulrich. 
PLATYCERAS (?) DEPRESSUM U.andS............. aleMorels alelete wlalede Olde cts w/0:« tele oblast 
Two views of the type of this species. It preserves the shell and was collected 
from the Ctenodonta bed of the Black River group, near Cannon Falls, Minne- 
sota. 
839 
838 
840 
840 
843 
837 
1068 
1069 
