Figs. 
Figs. 
Figs. 
Figs. 
Figs. 
Figs. 
Fig. 
Figs. 
igs. 33 and 34. 
Fig. 
Figs. 
Figs. 
Fig. 
23 to 26. 
24 to 26. 
28 to 3l. 
35. 
36 to 38. 
39 to 44, 
39 to 41. 
42. 
43 and 44. 
45. 
PLATE XXXVIII. 
VANUXEMIA DIXONENSIS Meek and Worthen ...............--e cece vere ee seer ecee 
Lateral, anterior and cardinal views of a large cast of the interior. In many 
specimens the anterior sulcus is deeper than in this one. 
View of the interior of a right valve, as shown in a gutta-percha impression. 
A smal! left valve which preserves a portion of the shell. Lower limestone of 
the Trenton formation, Minneapolis, Minnesota. 
WANUESE MLA “DDXONENSISs VATS INSUMDA' Mee WaTinnsisieleto cls crejatele sare elele'eyrercieier « eteisie 
Anterior and lateral views of a perfect cast of the left valve. Trenton limestone, 
Minneapolis, Minnesota. 
VAAN UERENETIA GER, ODTUINGD ATUAN SEDAN SO arch afojeye vel sfeleieseisseletetstalecrerensre se vetvaeere) =talefels =iofekome etayote Voters 
Perfect impression of the inner side of a rather large right valve. Geol. Sur. 
Mus. Reg. No. 8319. 
Lateral and antero-cardinal views of an entire cast of the interior. 
Respectively, posterior, anterior, dorsal and side views of the cast of the interior 
of a right valve of a small variety, differing from the usual form of the species 
in the more evenly rounded surface of the casts and greater incurving of the 
beaks. ‘Lower Blue” beds of the Trenton formation, Janesville, Wisconsin. 
VANUXEMITA OBTUSERRONS) Wilrichy yet aiter-lejctelaseielviator/<lofeieiniclsiolelereterenels mia peje cle rctelete ntaatot sla 
Side, anterior and dorsal views of a good cast of the interior. Lower Trenton 
limestone, Minneapolis, Minnesota. 
The hinge and an external.view of a specimen retaining a large part of the shell. 
Dixon, Illinois. 
VANUXEMTA/SUBERECTA,- TaSPra tisha e qaeincisoicctaie sci erties onitis: os ee cre eee arene 
Three views, dorsal, side and anterior, of a good, though rather small, cast of the 
interior. Trenton limestone, Beloit, Wisconsin. Geol. Sur. Mus. Reg. No. 8328. 
NAGS Up- donut Renin Dy) Oy ala. in Sod omiec biome wucodGHontonobooeNDDoN demacaneaigebanbors 
An internal cast of a right valve. Trenton limestone, Minneapolis, Minnesota. 
Lateral, anterior and cardinal views of a specimen in which the right side is 
preserved as an internal cast, while the other retains some of the shell. 
Trenton limestone, Cannon Falls, Minnesota. - 
AVZANTU ER MAS CRAIN SIA AEDES YD, ccehefatolaieystieve:c ste) ofollohsin-ccteneiets jejetalalevavelaia elaiereis telaierekel ietehaxe: aieeetear 
A sharply defined impression of the inner side of a left valve. Middle third of 
the Trenton shales, Minneapolis, Minnesota. 
VANUKEMIA’ UBBON ADA, Ins (Sp sinensis seme ci elses stovelnveisicts n/a ioielarelettnietafel seerereraieiel etemstets 
Four views of right valve of this species. 28, anterior; 29, the hinge; 30, cardinal; 
and 31, lateral. Middle third of the Trenton shales, Minneapolis, Minnesota. 
VANUXEMIA HAYNIANA Safford, sp 
(See also plate xu, and page 479, fig. 36, Iv 
) 
A cast of the interior of a small right valve. Galena shales, Kenyon, Minnesota. 
AVZANIUESG MAG ELEY EMOENGA TIS, «WL GE sayoyaro cach ats opere elerereletetele oral stetele ef cistevenslenesotcieiatela/ctete eiarepemstc 
Anterior views of the two valves shown in fig. 34. 
Casts of left and right valves of this species. The former was found in the 
Trenton limestone at Minneapolis, and belongs to the collection of the Geo- 
logical Survey, in which it bears the Mus. Reg. No. 5100. The latter is from 
the same horizon at Cannon Falls. 
IWANIUEE MEAS NTONAN (2ST 11) Wil GHlel Gey S plies ere ycterass otetwisiss ohalevelciesaiaateleletete eters leteveete eta 
The left side of an entire cast of a rather small example. The anterior margin 
seems to be more oblique than usual for this species. Trenton limestone 
(2 “Upper Buff” beds), Rockton, Illinois. Geol. Sur. Mus. Reg. No. 8325. 
WANUEGE MEAS SUBIR OT UINDD AYE ENS IS) = car ra-tarsls,> aoa loretaualesetetarste eietetole erafote<telatak erstelerere everiaterare 
The interior of an imperfect right valve. 
External view of a left valve, imperfect in the postero-dorsal region. 
Outline cardinal view of the original of fig. 36. Upper part of middle third of 
the Trenton shales_near,Cannon Falls, Minnesota. 
WAG SAOp:G MOON WGI PON AIWAS Soh Clune qocooncans saoccde de 100 adsanod cans Gonanoosgooonyonae 
Anterior, lateral and dorsal views of a nearly perfect cast of a right_valve. This 
specimen is of the average size and proportions. 
Cast of a large left valve that has suffered slightly from pressure, causing slight 
differences in the outline and the anterior side to be less abrupt than usual. 
Side and dorsal views of a smaller cast of a right valve in which the anterior end 
is very obtuse. Middle Galena, Fillmore county, Minnesota. 
WANUXEMIA (SAR DESONDE sUIGI CHI eisicv-y-ltuatrerelstase’a aretarcteie eenaiele ra atersteotereieasie nie steketeetetetchsteme 
: (See also plate xxxvur, figs. 17—19.) 
Interior of the left valve as brought out in a gutta-percha impression of the 
original type of the species, 
551 
552 
554 
553 
553 
557 
556 
560 
559 
560 
555 
