Figs. 40 to 44 
40 and 41 
42 and 43 
44 
Figs. 45 to 47 
Figs. 48 and 49 
Figs. 50 to 52 
Figs. 53 to 55 
Figs. 56 to 61 
56 and 57 
58 
59 to 61 
Figs. 62 to 65 
62 and 63 
64 
65 
Fig. 66 
Fig. 67 
Fig. 68 
Fig. 69 
Fig. 10 
Figs. 71 and 72 
Fig. 73 
OYRTOLITES SUBPLANUS, Ulich ...2 ive) ote Oe bythe ag terse avery keris eal cee eae 862 
Two views of an incomplete shell, preserving the surface ornamentation. 
Trenton group, Nashville, Tennessee. 
Parts of the dorsal slopes of same, x4 and x2, showing the strong transverse lines 
and weak pittings characterizing the species. 
Lateral view of a smaller but more complete example, with the surface markings 
indistinct; from the same locality. 
CYRTOLITES PARVUS Ulrich........ soosdeseNed Sao ddsae SABI SS seOUbobwS3o5 Sano dosES 864 
Three views of the type of this species, two of the natural size, the third x2. 
Utica group, Covington, Kentucky. 
CVRTOLILES DISMUINGIUS We BOG Siete occas ctclere te cre nie etal cis seolere totes relate state stotele tee fereieeieete 864 
Two views of a very perfect example of this species. The surface is ornamented 
almost exactly as in C. ornatus, so that figures 28 and 29 of this plate will serve 
equally well for both species. 
CYRTOLIUES CARIN AUS SMUT ORE teeters qulelersticie el trcenetslereremarncisteie sei o eueaetelaatste eter tet= 862 
Three views of a small but characteristic specimen of this species, x2. Utica 
group, Newport, Kentucky. 
CYRTOLILINAENEELD Wie AG GILT Tes pslorwm yeti ocrie step sohts faice etekeyae elektro eel oleic 866 
Three views, the first of the natural size, the others <2, of one of the original 
types. The specimen is a cast of the interior but the shell was so thin that it 
preserves a distinct imprint of the surface markings. Upper part of Trenton 
group, Covington, Kentucky. 
Ley aKesKoiwelis) CH UocHAMONYN LOllatelae ss oh ga ncdc aroun dente ceceghbracdascss6 4oddo t40ncoeRd6 925 
Dorsal and lateral views of a large specimen. 
Apertural view of the largest example seen. 
Three views of a third shell, this being of the usual size and proportions. 
Trenton group, near Danville, Kentucky. 
OXYDISCUS SUBAGUMUS MWUTICH ciaere oroccte eek ereieie o RE = pr emeerals ete aires aie alot bial tet inde a eiavolelslolals 913 
(See also plate LXxxI1) 
Apertural and lateral views of a nearly perfect example of this species. The slit 
portion of the dorsum is broken in the specimen but has been restored in the 
figures. 
Transverse section of a whorl, showing thickness of shell. 
Lateral view of the remains of the largest of twenty-three specimens. All the 
specimens are from the upper part of the Trenton group near Danville, Ken- 
tucky. The figures are slightly magnified (about one and one-sixth). 
CONRADELTA “FIMBRIATA: USA0d tis ce «schlttrtvne casos Pletctieteinetv esis vctetelerert | witha steleielat 907 
(See also plate LXvIl.) : 
Vertical section showing transverse sections of all the whorls and portions of 
former apertural expansions about two of the inner turns. 
(Gforeuni sic. Cepw.uspoyich 1Oshatels) So o5squenG DoBbae Goon cobb dboponesosndadoSnoaeoeocoed0s 908 
Transverse section of the last whorl of specimen figured on plate LX VII. 
HELICOTOMA UMBIRIGATA U5 GUS sereek | cole rep pop iel<fale eit eiere e ayriese epaiminid’ biele seb Vel clea icl=ts 1034 
(See also plate LXxIv.) 
Transverse section of the whorls of a specimen from the Stones River group at 
Dixon, Illinois. 
ERE GICOLO MAR VER TIC ADAS MOLEC Hee teerer tere rteintelete he ereletare/oleteretetetevelieta tetetnfaleyalietslctalo(oletetetaleletey sts 1035 
Transverse section of the last whorl of the specimen figured on plate LXXIV. 
HOCMIMOPTLER DS 1B HDOLUHIN GIS wl ccrils CUS icdatetaraialelscetcte ete let-iectelaraieteleleie rei ieseueeareterelstetaeistetetars 1032 
(See also plate LXxTIy.) 
Transverse section of whorl. 
ECCYLIOPTERUS VOLUTATUS Whitfleld Sp. ... 0... cence ccc ee ce ccenanctes cnaceecercs 1031 
(See also plate LXxXIv.) 
Transverse section of the last whorl of two specimens, one with the shell, the 
other an internal cast only. 
ECCYLIOPTERUS TRIANGULUS Whitfield sp.... ......... eee eebsieets niches es ai ee Lert 1031 
(See also plate Lxxry.) : 
Transverse section of the outer whorl of a cast. 
