ON whe
ie egret ae 6
bev ett Way bart
S
ema Lapis COU A © ep aw ~
~ “ "7 - yd ty DP acew re hr VARIES OY: oe: ope Sates
we Partin de adn GOP WG br tara oh ‘ x Serr
: : ; Oe hey 2 SOG OA TE ee
peaiecaeecie: " PoXenestetvate : : : . 5 E eae ar ane
Bebb eave boos » : . ; & &0 -
“ena ona A ~ ome -

, = ; Oey

A a i OR A ¢

<2 ‘ oie ne

“BOG SY es :

Soar : inte : sew ba diam bw
. nd “he ~ - . wip 4 ere ned Ce toni

“ f - * > “| . - AKT ating
: 2 $243 Fr > : y basse nee vee r ty nh
he he ete e 5

st
ise

: : ; ees Aabebuo-teeneghen poet et
‘ “ . Arye ery
. ¥ ’ ; ee ~~ ae Seoese
a : ma - apa ion Ratner . : ~ : : ae aa oew aa.
new r My “ Pari - a lite - w 2 ~ _ - ¢ > 2A Dee dew
Rath Bheapetiot : : - ° “oes : p

Ce Gee loathe Bs

A

“oe
fn Betin olen ter

* Deh ge

peated dient 4 wa eared ~~
Sa ete aie wend te re GAT
- : : < —— Sins ebaied
Oe eS OY SSE ST BD y- : ew
> O-$ 5D bay = ® .

Senne

0-4 0 Heneent~

ne
haat bern ger oR
: : = : : os ‘ ‘ Ma Boe Bot eo wes OED Wet e

Paras

ere

= Stes ant athe
ot

= Sonate
- Seer Cacent
aS ee FP aDE F-BY + OS Be Oh tld.
a Wet
SS PIPL & 69 ord 6

i oS
ot Brn t ee Kone <I * Pipa dobet ener

: us tom ¢ , " Leeandiguidisien aera a ade ont .

AW Te Une mtd

re

es
-

- TS ioe a ee
. . , r - - . . eae
os $+ esgaew> - - :
Kae GN
aon
rer uwy Comoe

eae
a —. ar,
<s “« ~~

"espe Se
, ao

‘ iis |
et

fF

Say oP) MAT le
v8 iy es
. Va
ee : Wars

i? c > j ” ( yas) a.

7a

no atte: Sa
pice /;

DEPARTMENT OF THE INTERIOR.

“nifD STATES GEOLOGICAL SURVEY OF THE TERRITORIES. | aye
F. V. HAYDEN, ut GEOLOGIST-IN-CHARGE. Koa te

1%

ee R J

CONTRIBUTIONS

TO THE

me.

5

JOSEPH LEIDY.

*

DEPARTMENT OF THE INTERIOR.
Pr fe REPORT
. OF THE ‘
I) STATES GEOLOGICAL SURVEY
: or
fete “TERRITORIES.
FON. HAYDEN,
Fie, UNITED STATES GEOLOGIST-IN-CHARGE.
IN FIVE VOLUMES. :
j .
ma. j oe
WASHINGTON:
GOVERNMENT PRINTING OFFICE.
US7S.:

19 get atte ; de. ve ; =, af r4 sr iled ah us
} 2 ¢ * : al rie mf — + > 4 7
Tie IHN fa Beldie, Ah « By Ss

: an i he ng A
5 Z ao - 4 vay i oy bw! "Bh )
x
é §-Fuo | am i ® wy
b . 4
i . : * os -
ue : ‘ .
“A
La "1 ’
‘ f J a ree bet :
ts i
*
~— -
x *.

bet T ik PO.THh SsHEC RET A RY.

Sir: I have the honor to present for your approval and for publication the
first part of volume I of the quarto series of reports which are intended to
embody the more original and technical results of the survey under my direc-
tion. The present memoir on the ‘ Extinct vertebrata of our Western Terri-
tories” has been elaborated by Professor Joseph Leidy, the eminent compar-
ative anatomist, and will form one of -the most important contributions to the
science of extinct organisms ever made in this country. This memoir will
be followed by a second part on the same subject by Professor E. D. Cope.

Volume II will embrace the subject of the extinct flora of our western
Territories; and it is the purpose to make it as exhaustive as possible. Pro-

fessor J. S. Newberry is preparing the first part and Professor Leo Lesque-
reux the second. The well-known reputation of these gentlemen is a sufh-
cient guarantee for the value of their work. ;

Volume III will include all the materials collected by the survey on the
subject of extinct invertebrata, and will be most carefully elaborated by the
eminent paleontologist of the survey, Mr. F. B. Meek.

Volume IV will embrace the profiles, sections, maps, and other illustrations,
with descriptive text by the geologist in charge.

Volume V will contain separate memoirs on different subjects in recent
zoology and botany, prepared by several authors. All the new and imper-
fectly described species of plants or animals collected by the survey will be
studied and fully illustrated. All these volumes are now in an advanced state
of preparation. In presenting to the world these important contributions to
scicnce, permit me, sir, to extend to you my sincere thanks for your intelli-
gent sympathy and hearty co-operation in the work.

Very respectfully, your obedient servant,
F.V. HAYDEN,
United States Geologist.
Hon. ©. Deuano, Secretary of the Interior.

VOLU MB. 1.

VERTEBRATES.

FOSSIL

en

a 44 - a 4
* : yi an We ay ons .
- > a a A f. 7 7
‘ é - ’ we Eoin 7
a=, oe} Lae eae eee
reese “SPT f tai atl ay oe
| dy Poe Pa “Wh BaD C1 lS Ee eae
; ; J + Pi av
on a : at /4,
7 nee Ch Sete ee
, hi ivi wich s STD Oo eee fe eae
A i a? ' ie s , ‘ ah ‘ :
* 7 ‘ “t a7 ‘

TO THE

THE WESTERN TERRITORIES.

PROF. JOSEPH LEIDY.

“
.
>
‘.
-
‘
—? Af
: ’ \-
-
te
’
*
.
«
-
-
.
‘
.

Pt Scie he
OT cen eg Be

4 J
vs ” a
> =-3.%
“«
ons “
ecient ate ye:
2 & at >
{ a aa
yh a ee fe a a)
4 d ch oP 8 eee
_
’ motlin (A arg oq a

tage y Pats Sete eee
; er rere ae {i

hae eA
. eee dee ol On.

ae Ribs er PT ee

wre i
r et 094’, ae te

“ 2
* 7 % ’ ve cee
al tee oa}
= = “«e % Say res
Dy ary 4 ‘
"4 Le
: ae oS. eo be hid lest
is f H bs
; -
ee —" we
. ss ~~
¢ : Bang
bae
-
- * “
.
a : .
’
a -
, ‘
.
. "
.
‘
‘
.
.

TABLE OF CONTENTS.

ZEB HVAC Bieter ayaioret aoe sjaict slat clots cl aiaivielcicieis ee ie at cisrala| sero a arc state naiacle(eve delays ae ceeenseeceicnicce sees
EXTINCT VERTEBRATE FAUNA OF THE BRIDGER TERTIARY FORMATION OF WYOM-
ALIN Goel BYES RUDD OUR Gers ieee eter oe ase e eheica sic ose wi cectrsee mea seiner acisienclertivaaieescci westce
JESAMOIDUCIEOIN ead cone ban peue Coan sacdes sts Oa 560s Beno cae sob asset nen dees Coo e epee ee seer
iL NGI TDS oe el IO eA len ety ee ae oe (se bbste ges 2a ee
Ordergrenssodactyldmamesin aa sae aslo sale ieee Soto ln et ain ise ecrisernsised~ Acecelce emi ccces
JERE RIE OOS con cass sano sordoe baSene tone sete seewed coed Cescce sesso esses oneness nSecco eee

IDTENMTONIOS, .oosss cesses sosdocsssce seacos ssasss s25ses sesls6 -osss5 oes tS sesesotcoesco Stee
JED MAIS cooces eseece coe sess secees os eseS tocsse sane Sreceacoscee careers peelco gece csecue
PEMA. cosh seen EHeQ HOO cosbnS been LeonOU RES CLOnSe SReocEeEEe EoseeceD casciead
GREITIINY ob Jo Lind Tee ah pe ie ane ake Gee een ere yO SAT Oa Ee ee ee

MOMS US seane sates cain, ocraiavata) aaiclena tice eecar acini Swe me erenicawiaielainwiaeuics eotelacee

LODO PRGSIIED . 5455656 5455 cabs Coeonnes be sabe bec cocoa ee sdeesens Saen aban Soo ese eoee as
GRR OME S20 can ece Deas oben SSoocs Caedbe oseeac Secbor Bese eeooae -een Shee
(BNO POSUS\ntcier alaisa ene a= = elma mim mine) nim|~ aim) le ieee enw ene ee oan oan nen ecnase

QHNUIS woes po scileheeodgsstoe odes boseenedsouecobegcse saotSc Bh ieese anes ceesee

NINOWISUS coos cerns espa ososde Joeace seobos coeeclosd dee sodcos sess soe a sasoeSbegoesus sonKae
GUYDORINTS) .oSone Sho coo edovndeBek condes coaces Coeg nade coao ccso coda geen Coe RSE EDS
JORGE OMSsoccas ceooss cootae eee siee Fece ee ere sce seas SSS ee eer a -ooccR a Cea Sodeceene Saee

INGUM RC HIS INE eee ice ting ema iiemiasa meet ec ccme so senelccccemiscs eae saeleurcnus cose aecmticn salts

TELWaVE Te SARL cu = SS te ae Pe 2.

TOT OUP OUOSUMLEM ORG eRe na piananictwelasncseminme Macaw em massac ocicic obeaghcncslecias celameacens
Meni Meee ee selec seeemieeenmameaciniccaalem tans nm cco tecsiceescerscsbhcc ccs sctedscke

CONGO JANET cco BER EEC On O0 COE Sa TOOE ES CISCDOCEIAC EE OASeBCeMEEE rr: Sem. SS Ae ee ae
IAT AIM BWeearatnnte(=imia)=(2\='~mim| ein wivinm siamo mn wie sme wines eee one enn tem ewe eranas cannes anne none
delicatus ..---.. Mae eie eee so in eincelgichGe ne! acimtemic cheese macs peaee ecls aces cen

COMEHULO Le merete teteatetee ee ete ets celal ele io cielsiniciwin e etiala wie nsincisinlacesieniie admeleson ec kes
WOLIGHUISSIMN Spee enter CeiE aeteth eine ee cie nce cle ie nne clam carainima neta cee craalsal me seehmies

NLU MVS eee eee eee seisisaminicese sae micm seis eeeamcce acajasciscmomcmmnieiiners® pa a ca
OndenmOuineevOncimnte arse erate aletnsisieline wicpenine cise cinio s micincieisicipeiseuneite ous citar stelaie cc sleaimmelinmicle
PEIMIOLOLIREEE REM ene a ente Maes ecnibcnmae case sm cnckicmas secidcepschee ctcs ends Scones nec eos $

ENORONT Shas Sood CO CSoO ACEC CeCe Ieee ODA SOE PROSE nO A SOCIO Gt Sa ea ae

69

for)
©

~~
_

79 9 41

pm OV Cu CY Re

S CONTENTS.

MAMMALIA—Continued.

Order Carnivora. Page.
INCAGTOR \iae0ckienh a wn ala ones la pa ie eee eee eee Pack. chan wee snsine abil > an 118
OOS ins 0 .n.csw'm wry okies Jp of ccaetieet anes te ee ia nie ee a ee See See Leet 118
VOTER cnec acc cauc sc vnunivone teeeean dene oul eka ada dane tddd dare Caeeee yn cee 120
Order Jnsectwone;.ccnen!s cdiiansmpe ace came aaa ee eae aon wi We eet ete psec Se ee en 120
QMO YS < engses ice weed bocce come ene menica same leee aay an eee ee ee ne ee ee ee ee 120
CALTON ccs wn pace ewe wine poe are See eae Sl eto isin eee 120
Pel AGOGON \ one win’ wens) asic m miele sel elw w= olimseie ie stmyecec a let aael iets ed 122
VOIDS 2 ics une cc cues chwkwc ss 'wonvicnnnan pavpesatpeak fpap aba ae delionsas aged eee 122
WV ESDBRIUG ou. wn:n daca noone ing mora eemniae de te aah waielncle o's ieee ae a or 123
INGIPNIG. .. - = Secon sw semen Vneme a2 Fene/re cub) e=oeerin eee dae grocecceeee peeeeaes 123
FElOMNOMIOM «oon bwin dssicn wins ernie cote a any wae eee ee eee Be min oe tele eer ee ee ee
B vo] Oli Sa! bl Dt 9 Rega ae, SES nea pee = ge an ot tn eBags pa. k measles ee oe ce ee ie a 125
Order Crocodile «2 nn 1a sshs bene ow ars cwclaom ons pipet ek ae amps wines dete beta eas ae 125
WROCOGIIUG = 20 ka 2 4 is eae a actn ope ee sas be ee ie en od mae cee Geo eel ei rr 125
DPUNG. = oe cee ene aera bab eswise we bases annie mn aies soe eila a nnn e eee nine se ame 126
Bliiott ....-. <=. Cotice dns mews watahuan/-ae canes omen Suan e ieee ne 126
QT CPU ae alta er tp ge en vs eco mw mre pt ea ie
4 Wy''2) 110 Ci (1 eee rR Re me ale A St ee pa, eee a a ye we Rare BP ee So te 132
Corsont =. es ee nen eee Bene ews lose eeee wie eee ane ee ees cee oa ee 132
DTT 9 ee es ee ney rs oe eS RES SEs Aha EAR see scee St 140
WY OMNIDEGNSIS oon oc ate pewin es aan eee ae mae eee a ee 140

Ba phen ys oct < a omom em melas mee pea a i ele lip oe ee a ee 15
WY ONIN PON BIS Eee ose elm ire ee aa 157
BRON ae wate ame we ama ee a rae ee ee 160
PATILO SD como wim mw mye te oa pm ve et a el lil
Ginstemonne tune e ase en ee nee ee ee ee able ae nie eee were scene en eeee ee 169
ONG SUM. See woe ee ee ee wine ee ee eee aie eee 169
SENSIS RNY BS te ta ee a 174
ALCNATIUS 2-5 -slcon> Oe n= See erie sop non eee 5 =e tee ee 174
ANOSLBITS & =. 52's tae shieseecelenwe Ses pe olen emia oS peice Pio ieteele lola a ee 174
SN ee ee CO Pee Giant oo tase Comes aes mee ei DEST esis l acts 174

d by) th'8:9 Sen Once = ae reec otk CHioene Gnome ao ob Ce tnO> senor mene ers = eet 1S l= slss cle 17
guttatus -.---- 2-2-2 22. eee ee ee ene cee ene ce een te ene en eee ene ene e eee ene one nee 176
pb Ey Yc) 0133 (Renee Ie OOS CURE PROS Oooe emer noe Bete come conmokese LLL lel. 178
Remains of Trionyx of undetermined species --...----.--. .----.-------- Mee ose: 180
Order ‘acertiliansae jo see ee ese sea ome ae na ea aa ae ee eee eo 120
RSET fen Oe ee BEER OCH ae~ ange Seer ada Ones Oona Mee ees ae Sb - 2 oblate) 181
ONSIGONS 1.222 ee sees seb ec PSs eco ninie es 4a ooh acaece toe cicin clase wc amet er 181
MAJOL <-- 2 kein conve woe sae ea ind oat a al ew iw 182
Glyptosaurus.---....-....... SO eee Sees Hone See 5 a ee se 182
@lamel eos = sca Sa a ne a a ee a la el 184
POTTS UNTUUS pico we mt ne tel it 184
BISHES |. s22eeo No Sorc ce oe ie Caesarea tet te Re henctel o lene es Sea el i a 184
Armia (Ero Gerrnia) Wim tegen SUG ae oat mie lm a cm 185
MeCG1F 2064 dsos so ME Sass Saves ows ccecins aac tieceselssescees=s eee eee 188
SSSR CLAS Yue ew oe ee 188
SEE yp NN Ne 189
COL ANS ae we ooo oa wie memantine 189
ThepidOstews) <= 2-25) <== ~<a mam a ma 189
HN 20S- 4 Ra ea RNS SCIE RCO CoS MOC Manes Ce ae see ee ore soe s eben ttre see: 189
(9) saccsecsemestan schcr epee detecm mecoeelqnemes coon aoe eee 1S0
SIU es6 Boo S5 pace cane seeds eS ese g ose sas sone seo sce ase sass sss sss 22+: - 191
NOtaADI WIS <a :< as So = joe wees o Siem cols ce aieveisin ete ieee are een a ee 192
Pimelodus...-.-. Sactere cule SEAS Seine DEO ee ORO ne nace eee Poe eee ete be oe ee 193
STUMQUUS ooo Soe sina aaah tale aie ale ola a ore ee ee "ee
PHSTeOdns = a Ss ance snclcos clea Doan Seta eee See eo ee ee ee ee ee 193
TOUTE (ener PRET OOS SCO COS Dan Hee Bana coco Coes asta re asec eee eos t 193

i i

CONTENTS. 9

FISHES—Continued. Page.

REMAINS OF FISHES FROM THE SHALES OF GREEN RIVER, WYOMING.....-....---. 194

CHING 35 cccic. conden sa6u ode J ove a5 Seen Bebe CUSSEHSE BES HEC TE Occ ea tM Eereaa in Skee oe weene Baer 195

UMS eee eel een cetera me ce tsa sacee oe cere ee seine se aco uesacaan he seos5 6 195

PII Bi 255 Seates DOGS rian ae SOD EORe COME SSE RE Raa aree EMAC EIS CRe es tases ener pate et 196
DESCRIPTION OF REMAINS OF MAMMALS FROM THE TERTIARY FORMATION OF

PETE EVV PACER rua ie Vib bys VV OUMIUN Geo sees cena sinica cmos ste clastencis an ase aeiscee cos Saimse 198 .

SIVIVANY VIC SUIG TAs rare =o at oetete arias bie asia tales wile la = ors aietaaieeaiee ome o eticie ele ele citer eme wise dints sedis 199

Orden Ruminaniarsamacee eras aces meee eee eee ese e See mat ees coe te ea aea sissies ce h as cee 199

IN,GIBTCOCIGSHIS Soa8 Be andaceeeu Poem Asesernb ae HCE em nose serc A nO OPE SECIS ASC ASE ae Nae: amar peel 199

TP ONS) season cuatcsnect entmod ionesn Docooe ose seoees cectoe sesso sbeése meee 199

: So (i) Sodbeo ocak a sebocusdaonds RESBEC Or SEDU Eso OOCUROU SEE See aee ame 208

Orderisolidungulapeees= sees apes aA aae mace essen cae mcm me mecha see citecc Semint cone ec ces 208
DESCRIPTION OF VERTEBRATE FOSSILS FROM THE TERTIARY FORMATION OF

POE IDANAS, IMINABIR OLN NEON oop Soc Bae ee Oe ab Se See SmIG soe ae CES e OSE ees ise ear ae eerie 210

MAMMALIA ..---.. ee ene re Sie Saar he a See a aee Sane Boe Sale aeee ce noee cme ctateesccee 211

ORG JETIIUUINAG 2 eco ted OAR RS EM CEOS CSO SC or CAR se ECHO SEC ee Sore ee eee ae 211

QWHIO 02 sosccoseesen eee cope Soe sone seco deat cede Reno oSndns Coes DobeSsoos seeeecee 211

(COMPRIS won 2 gosta decodes p25 daseco 2obSa0 sede on Seen olooag ceeaibsncoo esos SESE 211

SUPPGIOIG conn conepeseoece seeeaoScC Bdind CLGU S ASaee OS OE ECIn COMPCO DC See Eeaeea sees 211

IE EOMONy see sa Ise eee cence jada Steere aeeaocenes Eheim leah tl aos ee a 216

Eyal Sige ayia mie me sacra Dinettes crew enamise Scie cnlencwen sacaSiacsebsccee *, BIG

AVETOOIGS INS sentecccce cesses A605 250 oF DESO WanT ond OO OI OCOD HAGE E soo SC Ae Oae or CEE aREE ES 216

FiRGSTOIWS) aodacqonqu c2UneT aH COCR ODAC Ce Seen Cee Rea EOE SERA Oot Spee meee 216

VAtUOns eee cissaicans Semrnas seocememoe James came Oem, aceciee Seeiswsieikiess a6 216

ONC CTPA ODI CII Men aaeriiaweals hie sown ee dce eos sae oe SCUEDUUCDE OS COOEER EBAbe Sere AeeeneS 216

Wicotylesssces Vat ceeasecics etic cine HBSS O ape SS BEE Se OEE EE Aer aee eee eee 216

pristinus ...-...- $505 sae eseoeS. Sasso 5 Sso5sJengSt06 ject ceSh oder bss essa ceases 216

EN OUMOMM MMe tee aa eam reer eee sala tania ac caeckeae Soak sjck enc co bese wcidn, ooeses 217

TET OTAMO? ice G cigs aad SOE SCOR OO SAD HESS CR ERE Es She SA ae ee ae ee are sesey = RAKE

HOE SWAG UE o3A stm Aodcio8 CL 89 JOG REY AE IRD ESOT BOSCH OT BEEP AOeH Se ED Oe See cee 218

ATichibherimmijecsseeces 22 = eee eea seen mene ceataes emcee senecse saescecceads _ 218

SAU ete Nees eres eee ssi Se teas ociaeetciseeuacsasewheisiecies eae 218

Cond omitaeee ats seri aeee ne Acinecinics Ns Se niececce. cacte toes ceicembaoes Aotietoeccs 218

OndenseCrissOda Cup Gacemnctaa ee eae iaisies lee Ne cise axe cmiclcinieoae wom ses Beas eS ceeab ors are aioe 219

Lophiodon.....-.- .- fe minle) es ateisie) elm inlwninfaie > alone wininia elm wimielslomielm oo vo ninaie mein smminnic wow anaicie anes 219

ULIN OC CLOSE eee oer mamieeee Ree Sa ciacl oe ee elas St oa wtieieicisvewesienclces Sascssnbe.-ceeee saci 220

LOE DENT oc occa Dae ge abc0e SOR OUBOO SOREED EEDo JEeHEACe DCS HOH ABaCeOserer cise 220

PACthen stash eee ne Jotbee canoe maeiae doce sooo base SoEeoAC eo sce See oaa= 221

IRIDGIRIUES soca gocaoc ccnp sHecca pone nonceonoceen dees boos dace so BSS oS Ee Bare isoe SeeEes bose ee 222

supremus....-. ao non ocacige Setlout ca Goat SHoOMO SOD MBOr ose beeiods Sosteobacnsr eee 222

Arig eLORMMMedCannV OO. =a ieee eee aces teaser sieenwacc<. <SSwse Nemacwcecue decinmaccat 223

EE) EO NIA eee eee ea eee ae eee em on naw o de eset sy ncwic's wp e/e tn sw amiee soma cemerceins ecu 223

SU IGHEN octet telco coeiche Qemebt Ce Sogr beanie wns oH iS SGC UO OD De See ISU See Seeer Sinha ames 223

NE HIASCONSIMEee eae aaa Ee eRe eee sh ecmeda btcisice Ceicic te onccmeweincieals lees ase csme 224

MIO PLALONSISI ee See Seer ne tee mee ee ae soestihs co cjse sais sos aa Cemccemiccsiceecassa see = eS

ORYRUNTMNTS coco Hoodnoseee oe oseosace JACRHe DEE Oe SH SO Bee eee Seeese Cooaeeeone sees 226

DESCRIPTION OF REMAINS OF VERTEBRATA FROM TERTIARY FORMATIONS OF
DIFFERENT STATES AND TERRITORIES WEST OF THE MISSISSIPPI RIVER ....---. 227

SVIGAR VIL ICAU Aen Dee en Emcee eee See mee Ee tigre mn ccis ceciciis tne aaieavane csisiowe =-aeiiiwacicme 227

On CuRGU Pi NOnCeA ane ee ene tee See teens ae oho Sata coe cana wecewe reese cteusss.ccleeceae ste cee 227

TRETINS o cic pe SUC BOS A GRECO ODE SCE SITE RSA EIT ee ol re ee Sosa e 227

MPWSISES, soso ores vonoes eeTemone Gane SOR SUSEEDSe RUB SHE Re bon tacoSbnete Scne> oothoge see 227

THPEHEUS, o.oo ete bs Sebo nos BESO noScco ESE ebGlSs DeUbeo bso ee oes eecceSs rere mrss cuee 228

(GERI) oo cbas DaRHOG OCS OS RES SSC ESBS SEE SOS SOC RT ie ea es eee ee ene Eien Ses ere 230
indianensis .-..-..----. Ee NR ide iy oe ara) er oie miakeeralsteai ae emia ne heSeua sie seis 23

Onaleie. JBRANRocaae cakes Gon RCE SOB EOS eng be GBNOE CITES BERGE CES Fern eee at iee rie eae 231

ISS OG Te eee een tees eee Sac ae dade Gaeta namtecleieates: doe cesiceeiees ance 231

GOTOH, Rob chcRene enc SOSH Eb Re CO SUIS ROG OSE CIE EEOC Cis tae ae eee ee 231

TUL UEN Ce ELS ee Nea ere Se et Se Ey Se cei areibimaued cote ss aoe sic 237

WOT ONDINE 0. Ags Saco ca aoe BAe BOOS DEO GOI CREE ORO re eee a eee ie ees 237

IIl—G

10 CONTENTS.

MAMMALIA—Continued.

Order Proboscidea. Page.

Beep bas aia an iia minis ts cperaregh crore mete alse meeps ts smear eet ee eres pale eee ee 938

AMEVICANUS eno0)1-n'c owls welce ame namiameleeeimer nine seas meets aie ee nae eran ee oe en 2228

WC Fep Nts} 0) o)-\ecio ao 9 Sooo Seba aaeSaa 0S Soo 5 Cee Sees soo 5eS cose Simeone eee Seae 239

COLOPACODSIG 3:2 /alscc.c vainieimisievartni loteye seiner isi ae eee ee ae ee 939

Order iSolidungulay trctn:ecctays sicherwtey aimimtaieioy atalaie late ate fet ae le extent ieee 942

EQUUS jock os ccccee. Js at artciae cin Carerectotms otenetiae an sane ane sine Sinn SRS Ee eine nee ee eee 942

OcCidentalis.2ccae Vins) sams cenmocencocmesclecsinsminece Chane ea ne eer See eee nee 242

THE) Dose mG ASCAEO Cae ricd C.2a 5-0 DlOSeE Sane sad on oem ShossoAaacasncegee Ace ooes nese 244

JENS SERUO ona pe eoeo caeeo0 GoSOsoodseca tons sate Sees asss+ aieini=\= me ewlwin alee oe neler ela eee 247

Protohippus’s: Meryichip puss sete em .olmi mata atelm = tel em almlee)celamlmle mls alate aera weet tenes neee eee. 248

Anchitheriuny <2.<-. 2. 12. toads se BSS osb Sos Sess S6cbs0 ceaasadecboo sone RE ere See oe 950

Phil} 00) Gye sepepeced Uso ses Soon cIss SOS aO Sabana teSSas pond cose Anse conscncos- 250

ALTOSLE |S siei ore mimieie = atm mimo oll) spe elimi lw eiini lm elon felnlnl ol mininl ol alow iota =| = iat oe 251

(OD) Peon peaOOEEGEs caeeaoca canon ssoScs sade sdoomeSodeiticoasoocces Sosssic eso conc 252

Order Ruminanhdenes sa ceuekences eee eaase= EOS AIO IOS HITE = NOOO TOUTS TSE G5 CoS SOSEN osaoc- 253

Bison shccpeesss cece ee ene sees seaieeains|= sislemiein steel sem ame eeeye ate ste oes ee ene eee ee 253

latifrons.soatese aoe eee eee aeeere esa pcearere ieimnpissnicisnieciafhenn a Jt eee eee 253

AteChOni ar aecwee oars Reise Otis ceeutelsties ee ne temerlacte nce Ee rer ee ee ee ee oe eee oe eee ee 255

JIB SoS neo eeae codes > ABS Con aeoUey SOLS cor doo cresshSOoondeRy scnose abescorces 255

Proecamelts seececedetececettmros hae bees sence see ee eee ee ee ene ane a 258

VAWEIVGMIENS So6e oson55 Sod0n6 Daos ROSS sesso8 SoeS Sete Sos86 Senos seek dese secs 259

Moralomeryxis eee oe ceo eoeececeae neater eos Bos ceeo pe comocnoany CAoAermaneacteas soccer 260

z SLO EWE Neon a aee Geese DAOC D CSO CON OBES0S SuInSoS HESSEN AOneSSHoaD Sabo bese: 260

CHE LONEA 28262 Ssn 2 Sesigac bes Sed accmanceetea ne ses oseeesetesnGoscne sce eects ee eee eee ae 260

DBMS ieee teat oct erie Bonne nnn een we ee ene een one ween ee nee wanes Boots se 260

DOWD soso posSao soeoes cade seo5 Hoss ote SbSes0 yrrccee pee ences ene ee eee enn ee 260

BISHES) o5od0 dics Sad doe Sa aceon at ceuiowe See leet een eee eee e Coe ees Sac eee er 261

Jammy (CHORIN D oo 55 5 524555 0505 Sn db sodas 50000 seosadocemes sessebnSooUoSSeeste ce coseos 262

MDE OHMS Sees coos coeo56 cop ast SaReSe coos onSaSS costes conSaD Toone onoooo ates doce cee sce 262

roeinel Boon SeoCstOSdu bona soSticcas deer sod ce sodaeouna scSbes Oase Ssesoete cece 262

IMO hY JMG soh6 =255 os55s0 S555 soscd5 coe8 tend osces9 205 sees sosRe eESEDS Ret coe Seni coe eee 264

Oncobatiscast 2 veces whe mex meee ace eae eee e ee emee sees See ecole eae eee ee ee 264

WEWMUERRO NTS: oao5 gsaece seceod sos0e0 Hnenes ces tones SaaS seeds Ssaese onoees osese 264
DESCRIPTION OF REMAINS OF REPTILES AND FISHES FROM THE CRETACEOUS

FORMATION OF THE INTERIOR OF THE UNITED STATES..--........-. 2.2.2.2... 266

REPTIGES so seo eee eee oe ee ee ee ee eee ee Sacoese coos sseser soe2 225° 267

Order: Dino sania: poe es saebels Ses es ae ee eine eee Sno ieleis eee Siero at cierto eee dses aS eee 267

IROOM NEWHO MN 665 cogacs cboScs Sooo SUSSSo copESD BES Sons doOSES socesecseced oesee Sees os aee= 267

Valens 2shssbiietesemianea eens cee eee onesie sete ceee ceeoee ae ae eae 267

Order Chelonid sso cek cs ec bees eseee Ss eee eos ets See ae eee eee eee ee 269

Order Mosasauria:. =< <<... essa Soe aes Se ee ee sone abe sea se Bee ee ee cee eee eee 270

Wy LOSAULUS;.35-ccrs mses eeraee ees ae sces ee seer aese eect acem. ssc eae 271

GN) NE Oe sos50 Soe6 sose0d oses SoSSbH SeSaSS doSedo Soros SoeES Cosseessoeecoorssee 271

proriger sx. 2 6: seGeleneae wes Mee oth Uden eke men mec hte Sees eae er 271

Ti@sStOS aU US era yaa SIE Scherer ee oS Sa SE Se ere SSeS ere ae re ee 276

CORVIMMENS) secs caccs o560 as09 5600 dace ss0Sce Sedo S455 cons bens aessences seasons 276

Mosasaurus’.:2 22 os 55 c5 oso sae SS Pe eae See ee eae ate erator aa Se eo. Seis ae i see 279

Clidastes)s..225 Vise Gosck sGSee sae she Bene lebistee tc ces ste eee een oteeweR Hee ois ctersre ae eee 281

intermediusss 25. os asses s/s Sesisee eee ssiseme saree cise Seetsclnasle ise Sate here eee 281

AAANIS 355.252 35.5. 05e sete a Daciee Sa ao Ne tee ee Se eee weeee Semaecios ea ce see eee 283

Order Lacertilia 22.252 sachca sa neseiscoee este ae cae ee ee ee ee Tae ee eterna cie sae ee eee 285

Tylosteuss- 262282 scccis sosaassssceanoese sees neem sees ees ames sta eee Secs aces eee eee 285

OMMALNS j23. 55008 Ja seee ocean aoa as Sele we sleiss sis cade sine eareie wie vos sisinierselata esas eee 285

Order |Saiuropterygiaz 232262 ~5.2sdsios saet Dench eee ees soe eee ee 286

Oligosimus) 225 2552 se cess o cscs ae eee eee ee eee ne ase sera a eee e reece eee eae eee 286

= PPPHNOBENTES) combos coscos Dooce seer coco gseoUoOssSes aSssoeesbSecSocesasasscccesons )§©=| StF

INOthOSaULUs 22 oae2 sesso toed acces Se oe SaaS was Sain eleree a Oe ae ieee Sen eee ECE eeeeeer 287

OCCIGUUS ho 2S cs 4 sesso SaeSa sos SSS cialei ta Smera aatels share lnyen ae erate ate tete acre clersavecieeere 287

PISHES Rass sno aoe ec eiseeae asco SSemno go25 opse cone esos smon coos shes conse scot eesceres 288

CONTENTS. nel
FISHES—Continued. Page,
Oniles? AIGHHINOTIGN aco sdenane soeese Gs65 ES ESAs SARE ES Seana anes eene eee Sea Renan a Seca o nn asee coe Bele!
SUMING) oosces.pdeose d goa0 2S 0S0 CSE GOO SEO SSO MSE Boe aasoe 5 CHAO BRIERE EES HaReee sa ecoReeae 288
Clad OGY ClUS tener etter (foie rote era lemetorin series aewisis hee eaise Oe eel snen cr sispisieceeea eee Sens 288
OCCICeTIPaliSeeenyrariet tee scteeielaro wae ea ee eaye kine Sues Se essence welviacerseeimee 288
EC HO OU Sierra cera stot iakaeta are terse Merete ara raloe tals oie arn) ncicimneabe Cee ee aoateise elem Sewn ae Sasscocec 289
SS anna cle SOS oy PAE Yeo ka oy ie ens See teehee 289
IPE ER NOG Somaredaus coopue 250 845.50 BE OAR Aen OSA ee oks G1) Se Ceo nS ats Coc eae ae a 289
GUIS) Bs SAO BRAS AOn BOSC S Ser See Ser ey Sener aren 5 a ata ee ot ee oe 289
OrderpUalacopterieerraes eee ces sean e aoe kn ee SRI ak ee eee ea iaaen.ce eel Skee teed es 291
SHIDO aes cacoabag sobs CB 2600 8eSa00 S 4one HCO BOO EDOS TAN None Ess SE Ree Peo e eee eee eae 291
Mp HAChMU Scare ay= seats at temas eoeiar as cle eevecis cina!= Aciaycare eine WSO satan aotS cnsd secs 291
UTE tens ee pet Fe latoteta areal avatar a ona RISA ee see See Cece ceeeeiosenece> 291
CAN OND Minent eee eee Sere eerie ran iad-misis bene ce pacers ator sn mies seine ma/seeeissvaesceces cee 292
PMGOOUNS conn aces cece. coU Hea SED 2S! 0500 SAO GoD Sb aah SaaS CAROat Os 1a 3e Case CHE Eee ee imma.
TE iowa Sonn BeOS eas Bere SEOn nas Bone ne OOo EEE Se Re nee eee ee ee 292
BRIO OS) toe od pecs. 005g SARC HCC GEOR] Denn CO Bene CeCe See eT e oI eC Tere ei ae aere 294
DUNSDUG) oda ascemaodaanas sau eo CEO SOHN HOE] Secs CGS Da ASP Aes BReOGEr eRe eer e- 295
PAS MOB RANCH emer Ceeeicic acs acm aneect pe setae acs). a nseee seco eeeesseee ceecet 295
WNASEPLLATLOSIOM eae eta als sae ma'am ele Perse cir atcl se enimoaeasiene tes ssa scaceccs oceania leu 295
aby CHOMUSHMOLLO Mea eatsmer olan ae ee aia eel ee ier Saati ee a aikena aeon ceinjeeseee s base eee 295
occidentalise-o- <2 -2-t -2200- BS aoe pee E Soe aS © He ete e ee 298
SVVILUD 3 LONs Ieee ire eile eo ore ore yor ch re oe rch inca aoemaiae Supe emeceemac scabs < Als 300
AGC Shoacidatipenoadc SOROS IO CA OAC OS CORO OBOE Een OE EE aE OE SS ya aE ae Re ere Sree 300
TTS Nemec ta ata) tetaeic la eat saisfoiotiee atatcelal jaivin wcice Sem nwencindslenince= smeclodas coke 300
(CAIRTUBIGO coon dtosdoaocge0U CHOCOU COCCOG OGRE ogee be TAB eB TER es AO See nee ae eee eee eee 301
PAL CALI Merrett Neato aie aiatatey siete atecinrseienewokwrenum « 2 Se Bee eee ee 301
Ss Oxyrhina.....-.-. esas SACO ecoteD SONS OCSn Seo SS) Ob Saod Goes OnE eso -SESe OS an eee ropes 302
exienigeeereate ser see oe besstee ere ee hie o brcmimecmien Racor Soest shee cmnnysmeeee 302
Waranan se Oxy rhin aie fote eo ales aise oratn slate lciawrelictalelas Pulse sce caissGebersaecce sdbiecaacens 303
OQUCCTS ociodon dacdde nSd coq geonse SodcOn ae Hee CAI OE CAE nr teers pee Ae a eee eee 305
CHUA CAUSE Seema eminem mea ae cle salaatentae aiaoe Rec pisGcalnalmelseceelsecelenwi acca cca 305
Oniler JOANIE bocce cacobe bese Ociae 200 qe OC ROG A EEOO: BESS AREA SE Ce Hae eee Ee 306
Bia Olpametesen tec eters atcte isc teers iois aiatete ate iatal ste elatalela\ clara iah tarele nie tae e iam sistemas Soe ea aac 306
NN CUS ee ae Pee ee. Meee Sane seme nee nica s <csemebtedeseetreeoa bee cee eekic 306
JDM OGWE se Se mbdoos sod nog Hoot ob odiodon ee Romo. ager qODe BER - EEE PESO Een eee Seer see 309
LEGO R IDE so Aree Stacinetonckitee nogOG0 058000 EESCES CSS ARO ERASED EOS SE EEe rete Sere 309

NOTICE OF SOME REMAINS OF FISHES FROM THE CARBONIFEROUS FORMATION OF
ININSING! SSA CSQR POS SOR EE AO Rete: Ree Oat eee a ee a a ee eee 311
ONG JAUAG MONG iio seco toss aodeerree bbe G03 MOO CEO OSE RIS SAO TII Cee DROS E Pere EEE COPA RU Sere 311
Clad odulsemeeeerm sac eteca enim slciaset ltaee cs eatninciniainte eet lel aetealiomie cared oesaloescccacescsause 311
ORCC ON ta lise eter testseise enc emeainees sateen obs c es ein cecyentenca se clese cal a 311
2. IRMBTCRIN DTS 5 sono seosc6 corine OSSgoo cons onoced coe aH setes os ee se cons Cee eee pee ceee 312
PROTGINIE) Sac086 ofS006 BeOS QO EROS 0500 CR OEOO CHOCO EBS E CL 6 eer ae ee eRe eeE eee 312
Pe ObalOdUsmemeteteere nists oeiae = oc cise oe clciieisiee caine ceicbrccee slesiee we aime nn on ewww nen cn es one 312
PIG RIC NTE! ga apeeOseat Sace ae eee ae eee ee eee ee - $812
PAR LOL AC AUDA metas stam (afoe cen (aiainietCucie! case asltioe ciclnielecivictcln lc sisal ewicie wtepaSeeviciiescscsessncts 313
SIGTOS cacao Saee Se SSRd Bel6 COCK OO SOS SU OOS oR ns eee ae 313

SYNOPSIS OF THE EXTINCT VERTEBRATA DESCRIBED OR NOTICED IN THE PRESENT
BY Viv espera tetas tse een srale as vated eseie en inte ce wiee ceils dae occas eececsacscdsevercoseew se bdes 315

oe A, Os
\

le pute ie s

a : é ee
Pine Gigallec ast a aia ae he <u
fame ts aR be stl dren mules "eer duis ‘Saale

is
.

j Ls 7 a

f ~ . Fee - shley th! a hpegnen ; 4 ave A, Ast Ficotlon: eae

Pee ecm e arc neg seh
; . ) . j 3 fs ‘ " ie Oe : } rep Ha ail oer na wih 4
F : ; _ 5 tin ala 5 ees
Tt ie! ‘ 4 r ~* 5 -v Pa Pitt a “epaarhel tk ‘ ane : pe Sse sgl
‘_ ; i
~ i w b:
5 7 ‘ : pie bese en Libs 224)
he Tra et soir: : 4 «
cy ey, ; ey
. Sik 2's ite weenie aualies tele eM cata “watd
. 2
a -

PHILADELPHIA, January 13, 1873.
Dear Sir: Herewith I transmit to you my report on vertebrate fossils from
the Western Territories and States. Many of the specimens were collected
during your geological explorations, and were submitted to me for investiga-
tion. Others have been collected by different persons living in the West,
and sent to me directly, or through the agency of the Smithsonian Institution,
for examination. Most of the fossils were obtained in Wyoming, and the
others were derived from Oregon, California, New Mexico, Idaho, Colorado,
Kansas, and Nebraska.
With respect, I remain, at your service,
JOSEPH LEIDY.
Professor F. V. Haypen,
United States Geologist.

PREFACH.

The present. work was commenced in 1870, at which time the amount of
materials as subjects of investigation and description was comparatively small.
A consiant accession of new materials, beyond all anticipation, has greatly
extended the work. This will account for the apparent want of system in
the arrangement or proper collocation of the subjects of many of the plates.

The interest excited by the numerous discoveries of vertebrate fossils in
the Western States and Territories has led to the recent explorations of Pro-
fessors Marsh and Cope, both of whom have obtained rich collections. The
investigations and descriptions, by these gentlemen, of some of the fossils
from the same localities, have been so nearly contemporary with my own, that,
from want of the opportunity of comparison of specimens, we have no doubt
in some cases described the same things under different names, and thus pro-
duced some confusion, which can only be corrected in future.

My investigations, in many instances, may appear not so complete as would
be desirable, and my excuse for not doing the work more thoroughly is the
limited time allowed for the purpose and the little leisure I have had in the
intervals of other and necessary professional engagements.

a

*

EXTINCT VERTEBRATE FAUNA OF THE BRIDGER TERTIARY
FORMATION OF WYOMING TERRITORY.

INTRODUCTION.

The following pages contain a description of fossil remains of vertebrated
animals collected in the vicinity of Fort Bridger, a military post situated in
the southwest corner of Wyoming Territory.

Many of the specimens were obtained during Professor Hayden’s geological
explorations of 1869 and 1870, but the greater part of them were collected
during the same years and the succeeding one by Dr. James Van A. Carter,
residing at Fort Bridger, and by Dr. Joseph K. Corson, United States Army,
the surgeon of the post. These gentlemen have diligently explored a wide
extent of country in their immediate neighborhood in the search for fossils
with the most intelligent interest. The results of their explorations they
have liberally placed at the service of naturalists by voluntarily donating
all the more characteristic portions of their collections to the Academy of
Natural Sciences of Philadelphia.*

After the present work was supposed to be nearly ready for the press, and
‘ the accompanying plates from I to XXII were complete, the last summer, the
writer received a pressing invitation from his friend Dr. Carter to visit him
at Fort Bridger. As the invitation was accompanied with liberal facilities
and offers of aid in exploration, the author availed himself of the opportunity
of visiting a region of so much interest, and accordingly spent the summer
vacation in a trip to the locality. |

Fort Bridger occupies a situation in the midst of a wide plain at the base of
the Uintah Mountains, and at an altitude of nearly seven thousand feet above
the ocean-level. The neighboring country, extending from the Uintah and
Wahsatch Mountains on the south and west to the Wind River Range on the

northeast, at the close of the Cretaceous epoch, appears to have been occupied

*In speaking of this institution hereafter I shall briefly refer to it as the Academy,
or the Academy of Philadelphia.

16

by a vast fresh-water lake. Abundance of evidence is found to prove that
the region was then inhabited by animals as numerous and varied as those of
any other fauna, recent or extinct, in other parts of the world. Then, too, a
rich tropical vegetation covered the country, in strange contrast to its present
almost lifeless and desert condition.

The country appears to have undergone slow and gradual elevation; and
the great Uintah lake, as we may designate it, was emptied, apparently in suc-
cessive portions and after long intervals, until finally it was drained to the
bottom.

The ancient lake-deposits now form the basis of the country, and appear
as extensive plains, which have been subjected to a great amount of erosion,
resulting in the production of deep valleys and wide. basins, traversed by
Green River and its tributaries, which have their sources in the mountain
boundaries. From the valley of Green River the flat-topped hills rise in suc-
cession as a series of broad table-lands or terraces, extending to the flanks of
the surrounding mountains.

The snows of the Uintah, Wahsatch, and other mountain-ranges are a
never-failing source to the principal streams; but many of the lesser
branches, dependent for their supply on the accumulated snows of winter in
ravines of the lower hills and -plains, completely dry up as the snows disap-
pear with the approach and advance of summer. The country for the most
part is treeless and destitute even of large shrubs, excepting along some of
the water-courses. The principal streams are fringed with trees, consisting of
cotton-wood (Populus angustifolia) and willow, (Salix longifolia ;) and the
valleys through which they run produce mostly rushes (Juncus balticus) and
sedges, with some coarse grasses, as Elymus condensatus and Triticum repens. —
Hollows of the hills and narrow valleys, favorable to the retention of moisture,
support forests of small aspens, (Populus tremuloides.) The higher terraces
and foot-hills approaching the mountain-ranges are covered with dense forests
of aspens, pines, (Pinus ponderosa and P. flexilis,) and firs, ( Abies Menziesii,
A. Engelmanni, A. grandis, &c.,) with a rich undergrowth of herbaceous
plants. The great mountains themselves present a broad belt of pines and
firs, from which project the rocky summits as bare of vegetation as the wide
plains at their base. Many of the lower hill-sides and hollows in certain

situations are sparsely covered with cedars, (Juniperus virginiana,) most of

17

which are very old in appearance and remarkably distorted, twisted, and
broken. :

The principal growth of the plains consists of sage-bushes (Artemesia tri-
dentata) curiously distorted and split, so as to remind one of the cedars just
mentioned. In some piaces the sage-bushes are mingled with or replaced by
the grease-wood, (Sarcobatus vernuculatus.) Wide, bare, path-like intervals
surround the bushes, or the spaces are occupied by scanty grass, which
formerly furnished food to the buffalo, now become extinct in this region
and elsewhere west of the Rocky Mountains.*

The fossils which form the subjects of our communication for the most
part were derived from the more superficial deposits of the great Uintah basin,
which Professor Hayden has distinguished as the Bridger group of beds.
These compose. the terraces or table-lands in the neighborhood of Fort
Bridger, and consist of nearly horizontal strata of variously colored indurated
_ clays and sandstones. As the beds wear away, through atmospheric agencies,
on the naked declivities of the flat-topped hills, the fossils become exposed to
view and tumble down to the base of the hills among the crumbling debris
of the beds.

The flat-topped hills or terraces of the Bridger basin, rising front broad
valleys and extended plains, form the most conspicuous objects of the land-
scape. A similar condition of the country, alternating with boundless plains
and great mountain heights, forms a characteristic feature of a great part of
the region west of the Mississippi.

The flat-topped hills, table-lands, bench-lands, or terraces, as they are
variously named, seen from lower levels, are usually called “buttes,” especially
when they are of limited extent. The name is of French origin, and signifies
a bank of earth or rising ground. The name is likewise applied in a more
restricted sense to the prominent irregularities of the deeply eroded and
naked declivities of the more extended terraces. The buttes therefore vary
in extent from a mere mound rising slightly above the level of the plains to

*TIt has already become a question whether the buffalo existed west of the Rocky
Mountains at a comparatively recent period. That it did so was amply proved to the
writer from his having noticed remains of the animal in a number of places, from ravines
skirting the Union Pacific Railroad to the forests high up in the foot-hills of the Uintah
Mountains. Judge W. A. Carter, of Fort Bridger, informs us that some of the old trap-
pers and hunters of the district had told him that in their early days they had seen the
buffalo in abundance in that country.

3 @

18

hills of varied configuration reaching to the level of the broader buttes or ter-
races. In the course of ages the wearing away of these has been enormous
and still continues under the usual atmospheric agencies, while the detritus
is spread out on the plains below.

From the lower plains the neighboring terraces, when of circumscribed
extent, appear like vast earth-work fortifications, and when evenly preserved on
the declivities for a considerable distance remind one of long railway embank-
ments. Frequently the terraces are so extensively eroded and traversed by
narrow ravines that they appear as great groups of naked buttes rising from
the midst of the plain, or assembled around the horizon closely facing and
flanking the more distant and extended lands as if to protect them. Nothing
can be more desolate in appearance than some of these vast assemblages of
crumbling buttes, destitute of vegetation and traversed by ravines, in which
the water-courses in midsummer are almost all completely dried. To these
assemblages of naked buttes, often worn into castellated and fantastic forms,
and extending through miles and miles of territory, the early Canadian
voyageurs gave the name of “ Mauvaises Terres.’ They occur in many local-
ities of the Tertiary formations west of the Mississippi River.

In wandering through the ‘“ Mauvaises Terres,” or “ Bad Lands,” it requires
but little stretch of the imagination to think oneself in the streets of some
vast ruined and deserted city. No scene ever impresed the writer more
strongly than the view of one of these Bad Lands. In company with his
friends, Drs. Carter and Corson, he made an expedition in search of fossils
to Dry Creek Cafion,* about forty miles to the southeast of Fort Bridger.
The cafion, or valley, is bounded by high buttes, and contains a meadow of
rushes, traversed by a stream which is hable to be dried up in the latter part
of the summer, whence the name of the cation. On ascending the butte to the
east of our camp, I found before me another valley, a treeless barren plain,
probably ten miles in width. From the far side of this valley butte after
butte arose and grouped themselves along the horizon, and looked together
in the distance like the huge fortified city of a giant race. The utter desola-
tion of the scene, the dried-up water-courses, the absence of any moving

* The same name is so frequently applied to different places as to lead to consider-
able confusion. When I speak of Dry Creek Caiion, I refer to a locality forty miles
from Fort Bridger; and when Dry Creek is named, it refers to another locality ten miles
from Fort Bridger.

19

object, and the profound silence which prevailed, produced a feeling that was
positively oppressive. When I then thought of the buttes beneath my feet,
with their entombed remains of multitudes of animals forever extinct, and
reflected upon the time when the country teemed with life, I truly felt that
I was standing on the wreck of a former world. |

The buttes are often specially designated from some supposed resemblance,
or other character, as Church Butte, Pilot Butte, Grizzly Butte,* &e.

As before intimated, the more superficial table-lands of the Bridger basin,
as they appear in the vicinity of Fort Bridger, are composed of nearly hori-
zontal strata of various colored indurated clays and sandstones. In most
localities visited by the writer the clays predominate, and are usually greenish,
grayish ash-colored, and brownish. When unexposed they are compact,
homogeneous, and of stony hardness. In composition they vary from nearly
pure clay to such as are highly arenaceous, and gradate into those in which
sand largely predominates, and they usually contain few or no pebbles. They
appear to be more or less fissured, and break with an irregular and some-
what conchoidal fracture. Exposed to atmospheric agencies, moisture, and
frosts, they readily disintegrate, and the declivities of the buttes, generally
entirely destitute of vegetation, are usually invested with crumbling material
‘from a few inches to a foot or more in depth. When this loose material is
wet it forms tenacious mud, and along the course of streams in the ravines,
the deepest and most treacherous mire. Baked by the sun upon the plains,
it fixes the drift-pebbles and other stones as firmly almost as if imbedded in
mortar.

In some localities the clays of the buttes abound in fresh-water shells, as
Unio, Melania, Planorbis, &c. Less frequently in other places they con-
tain land-shells, as Helix, &c.

The sandstones are more frequently of various shades of green, but are
also yellowish and pass into shades of brown. They are compact and hard
when unexposed to the weather, and are usually fine-grained, but also occur

*This name is applied to an extensive chain of buttes about ten miles to the south-
east of Fort Bridger. Judge Carter informed me that the name originated from the
circumstance that an old trapper, Jack Robinson, once reported that he had found a
petrified grizzly bear on the Butte. From the description of the petrifaction 1 have
no doubt it was that of the animal I have named in the succeeding pages, Palzosyops,
the skull of which resembles that of a bear.

20

of a gravelly constitution. They are fissured in comparatively large masses,
which assume a rounded form as they are worn away, so that a ledge of
sandstone projecting from the declivity of a butte will appear like a row of
cotton bales. As they disintegrate less rapidly than the contiguous clays,
masses are often observed resting upon cones and columns of the latter, con-
tributing greatly to the picturesque and sometimes fantastic appearance of
the buttes.

Many of the table-lands and lesser buttes in the vicinity of the Uintah
Mountains are thickly covered with drift from the latter, consisting of gravel
and bowlders of red and gray compact sandstones or quartzites. The drift
material is usually firmly imbedded in-the surface of the plains so as to
appear like a pavement. The bowlders are generally small, but assume larger
proportions approaching the Uintahs. In many cases the drift completely
covers the terraces or buttes, descending upon the declivities so as entirely to
conceal their structure. Usually, however, it accumulates in the ravines of
the declivities, leaving bare the intervening ridges of light-colored clays and
sandstones. Many of the buttes are nearly or quite free of drift material.
Some, again, are strewn with fragments of rock, consisting of the harder materials
from the terraces themselves, and these likewise occur mingled with the
drift-pebbles and bowlders from the mountain-heights.

The stone-fragments from the buttes consist of harder siliceous and cal-
careous clays, impure limestones, jaspers, and less frequently agate and chalce-
dony. In some instances they consist of singularly black incrusted and
rounded sandstones, somewhat of the character of septaria. Specimens of
these occasionally bear a resemblance to fossil turtles, and when found with
the harder crust broken they look like turtle-shells filled with a sandstone
matrix.

In the buttes in the vicinity of Carter Station, on the Union Pacifie Rail-
road, IT observed many large nodular and cylindroid masses of agate. These
have a concentric arrangement of layers resembling that of fossil wood, for
which they are taken. Many of the masses contain a nucleus of amber-
colored crystals of calcite.

Nodules of chalcedony with dendritic markings occur in some of the
buttes. These, together with the condition of many of the fossils of the
buttes, indicate the presence of a considerable proportion of soluble silica in

21

the waters of the ancient lake. In some of the sandstones, the fossil shells
have had their lime completely replaced by clear chalcedony.*

Occasionally strata of limestone, mostly impure from the admixture of clay -
and sand, are found in some of the buttes. A frequent constituent also is
fibrous arragonite, or satin-spar, in thin seams. Many of the bare mounds of
clay among the buttes are thickly strewn with fragments of this arragonite.

The stones imbedded in the surface of the plains and buttes, in some ™
positions favorable for the purpose, are highly polished from the conjoined
action of the wind and sand, and when seen in the slanting light of the early
morning or evening sun, appear like myriads of scattered mirrors. In many
positions, the stones, no matter what. may be their composition, are all black-
ened. The phenomenon I could not explain.

In wany places the stone-fragrents from the declivities of the terraces,
strewn over the lower buttes or distributed over the plains, are splintered or
flaked in a remarkable manner. The jaspers especially are often broken in
such a way that they appear as spawls from rude implements of art, or even
resemble the latter. Some of them are certainly the work of primitive man,
but the vast proportion, often scattered over miles of surface, are probably
accidental forms. These I suppose to have been produced by stones striking
one another in the descent from declivities as they have been carried down,
perhaps by glacial movement. The softer rocks of the buttes, those which
are too soft for stone works of art, are also observed broken in the same way
as the hard ones. In experimenting on some large splintered slabs of jasper
from the buttes of Dry Creek Cajion, I found that a quick blow of a hammer
would send off, with a ringing sound, a long sharp flake, reminding me of the
primitive knives or scrapers of the stone age of man.

Between the well-finished implement and the accidental spawl every gra-

dation of form may be observed among the scattered stones of the plains and

* Perhaps much of this soluble silica may have been supplied by hot springs still so
frequent in Wyoming and other Western Territories. Cold springs, slightly alkaline,
may have also contributed to the petrifying silica. In Pioneer Hollow, fifteen miles
west of Fort Bridger, I observed a dozen springs within the distance of a mile, the
water of which reminded me of the congress-water of Saratoga, New York. It is cool
and clear, highly carbonated, slightly alkaline, and agreeable to the taste. The springs
are circular, from 1 to 15 feet across, and are surrounded with dome-like craters from
1 to 3 feet high. The craters are formed of a siliceous sinter, which has been slowly
deposited from the spring-water, and is probably the accumulation of ages. The sinter
is brown from the presence of iron, though the water has no perceptibly ferruginous
appearance or taste.

yy)

buttes. The accompanying figures, from 1 to 12, represent some of the
flaked stones, most of which, and perhaps all, are rude works of art.

Many of the accidental forms, as well as those more nearly resembling
artificial implements, if they are not actually such, appear greatly to differ in
age. Some of the specimens are as sharp and fresh in appearance as if but
recently shivered from the parent block, while others are so much worn and
so deeply altered from exposure that they look to be of ancient date. In
some of these old-looking specimens the jasper, originally brown or black,
has become dull white and yellow the depth of one-fourth of an inch from
the surface.* :

*In this relation I may take the opportunity to refer to one of the simplest of stone
implements, still in use, and which, if it had alone been found among the flaked ma-
terials of the buttes, would certainly have been viewed as an accidental spawl. During -
my stay at Fort Bridger, the Shoshone Indians made a visit to the post and encamped
in its vicinity fora week. Being the first time that I had had an opportunity of seeing
a tribe of Indians, I felt much interest in observing them. While wandering through
their camp I noticed the women dressing buffalo-skins with a stone implement, the
’ only one of this material I found in use among them. A serrated scraper of iron was
also employed, but the stone implement was clearly a common and important one. It
was a spawl from a quartzite bowlder made by a single smart blow with another stone.
It is circular or oval, plano-convex, and with a sharp edge. The implement is repre-
sented in the accompanying figure 13, and according to Dr. Carter, who is quite
familiar with the language and habits of the Shoshones, is calied by them a “ te-sho-a.”
By a happy accident I learned that it was not a mere recent instrument incidental to
the time and place.

While on an excursion after fossils, in company with Dr. Carter, I noticed on the side
of a butte a few weathered human bones, to which I directed the attention of my friend.
On further examination, we found others, together with some perforated canines
of the elk and one of the identical “‘teshoa” above described. Dr. Carter observed
that the Shoshones sometimes buried their dead upon the top of prominent buttes,
and these remains had fallen from the grave of a squaw, which in the course of time
had become exposed by the wearing away of the edge of the butte. The bones and
elk-tusks were much weathered. Their appearance and the probable circumstance
that several years had elapsed before the butte could wear away to reach the grave,
appear to be sufficient evidence that the ‘“‘teshoa” was an implement of common use.

To this note I may add a remark relating to the perforated canines of the elk. They
are worn as ornamental trophies by the Shoshones and other Indians. In a recent
number of the American Journal of Science and Art, for 1872, page 241, in a notice
‘On fossil man of the cavern of Broussé-roussé, in Italy, by EH. Riviere.” I notice that,
besides a human skeleton associated with the bones of many extinct animals, there
were also found several flint knives and a number of perforated canines of the stag.
In addition to the common form of many of the stone implements, this is a significant fact
bearing on the probability of a common origin to the races of man. One of the speci-
mens of perforated tusks of the elk from the Indian grave is represented in Fig. 14,
at the end of this introductory chapter.

23

As the clays and sandstones of the Bridger terraces and buttes crumble
away, a variety of remains of terrestrial and fresh-water animals are exposed
to view. In some of the buttes they are comparatively abundant; in others,
they are rare. The fossils consist of the bones and teeth of vertebrates, and
the shells of mollusks. Fragments of silicified wood also occur, though
not frequently. Shells of the sandstones are composed of chalcedony; but
those imbedded in the indurated clays usually retain their carbonate of lime

The fossil bones are completely petrified; that is to say, their more per-
ishable constituents have been replaced mainly by siliceous matter. They
are frequently as black as ebony; and the teeth are usually black, with the
enamel highly lustrous. Often they are brownish, with a greenish aspect,
derived from the greenish matrix in which they were imbedded. They are
also found of a yellowish clay color and duller aspect.

Many of the bones are more or less crushed and distorted, : as a result of
‘the pressure of the superincumbent strata. The fragments are generally but
slightly dislocated, showing that the crushing occurred while they were
imbedded. The stronger bones are often well preserved, especially the rami
of lower jaws and teeth, and the smaller bones of the wrist and ankle.
Whole skulls are exceedingly rare, and when discovered are much crushed
and distorted. ‘Turtle-shells are among the most frequent fossils, but are
usually more or less fractured, crushed, and distorted. In séarching over
the buttes, little piles of bone-fragments are often seen diverging from a
prominent point. These, on examination, generally prove to be the remains
of a turtle-shell which, after exposure, has fallen to pieces.

Generally the fossils are sharply preserved; that is to say, they rarely
have a rolled or water-worn appearance, indicating that bones and shells
were soon enveloped in mud at the bottom of comparatively quiet water. In
the gravelly strata rolled fragments of bones are found.

Nearly all the fossils collected from the Bridger beds, and described in
the succeeding pages, have been collected as loose specimens picked up on
the surface of the buttes. No excavations have been made into the latter in
search of fossils, except to exhume a partially exposed bone, or some parts
of a skeleton supposed to be contiguous to specimens lying in view on the
surface. Usually only a few pieces of a skeleton have been found together,
and in no instance has a complete one been discovered which has been
brought to my notice. Generally, too, there has been no certainty that bones

24

or fragments found together belonged to the same skeleton, and in most
instances they have appeared to belong to several different animals.

The remains of vertebrates thus far discovered in the, Bridger Tertiary
formation represent all classes except Batrachians, and these no doubt
formed members of the ancient fauna; but their delicate bones have, as yet,
escaped detection.

The remains of mammals are especially numerous, and they belong to
many genera, most of which are extinct, and had not been previously
described or found elsewhere. The greater proportion of the maminals were
odd-toed pachyderms, whose nearest living allies are the tapirs. Proboscidian
and equine forms appear to have been sparsely represented. Even-toed
pachyderms were comparatively few; and ruminants, whose remains are so
abundant and varied in the later Tertiary formations east of the Rocky
Mountains, appear to have been absent. The other remains of mammals
belong to rodents, insectivores, and carnivores, nearly all of extinct genera,
not previously described nor found in other localities. Primates, bats, mar-
supials, and edentates are probably represented, but have not been certainly
recognized among the fossils which I have had the opportunity of examining.
The nature of the formation from which the remains are obtained is such
that we do not expect to find evidences of the remaining orders of mammals.

No remains of birds have come under my notice; but Professor Marsh,
who has explored the Bridger Tertiary beds with unusual facilities and great
diligence, has reported the discovery of specimens which he attributes to half
a dozen species of two extinct and previously unknown genera.* {

Of reptiles, the remains of turtles are, perhaps, the most abundant fossils
met with in the buttes of the Bridger basin. They belong to a number of
different genera, several of which are extinct, but others belong to genera
still in existence. Most of them are aquatic forms, but one at least was a
land-tortoise. ‘The number of species and genera is in striking contrast with
the single species, represented by a multitude of individuals in the Tertiary
deposits of White River, Dakota, and of Niobrara River, Nebraska.

The turtle remains mostly consist of the shells, often nearly complete,
and sometimes including other bones of the skeleton imbedded in the interior
matrix.

The remains of crocodiles, which are entirely wanting in the White

* Am. Jour. Se., 1872, p. 256.

25

River and Niobrara Tertiaries just mentioned, are frequent in the Bridger
beds, and represent several species.

Remains of lizards also, allied to the modern iguana and monitor, are
found as associates of the Bridger fauna. Professor Marsh has likewise
reported the discovery of remains of serpents, which he ascribes to several
species and genera.

Multitudes of well-preserved fresh-water fishes are found in the Green
River shales. They are chiefly cyprinodonts and herrings, and, for the most
part, have been described by Professor Cope.

Black, shining, enameled scales, teeth, and vertebrze of ganoid fishes are
frequent among the fossils of the Bridger beds.

The Tertiary strata of Green River and its tributaries, including the
latter, as indicated by the character of the vertebrate fossils, are much older
than the tertiaries of the Mauvaises Terres of White River, Dakota, and of
the Niobrara River, Nebraska. They overlie the cretaceous rocks, with which
they are unconformable, and they are probably contemporaneous with the
Kocene formations of Europe.

Attention was first directed to the Green River Tertiary formation,
which has proved to be so rich in the remains of vertebrates, by the late Dr.
John E. Evans, as early as 1856. From Green River he obtained a speci-
men of shale, with a well-preserved fish, represented in Fig. 1, Plate XVII,
of the present work, and briefly described by the writer, under the name of
Clupea humilis, in the proceedings of the Academy of Natural Sciences of
Philadelphia, for October, 1856.

In 1868 Dr. J. Van A. Carter, of Fort Bridger, in correspondence with
the author, informed him of the frequent occurrence of the remains of turtles
and other animals in the buttes of the neighboring country. The same year
Professor Hayden, during his geological explorations, obtained remains of a
Trionyx from Church Buttes. Colonel John H. Knight, United States Army,
also procured a vertebra of an extinct crocodile from the same formation of
Bitter Creek. These remains, together with those of a small insectivorous
animal, discovered by Dr. Carter on the Twin Butte, near Fort Bridger, were
described by the writer in the Proceedings of the Academy for April, 1869.
The little insectivore was named Omomys Carleri in honor of its discoverer,
and is also described in “The Extinct Mammalian Fauna of Dakota and
Nebraska.” The specimen upon which it was characterized is represented in

4G

26

Figs. 18, 14, Plate XXIX, of that work. Subsequently, during 1869 and the
following years down to the present time, the Green River basin has been
sedulously explored by Professor O. C. Marsh with the most important and
fruitful results. In the abundance of fossils and the number of extinct genera
and species of vertebrates. they represent, his collections are perhaps not
exceeded by any obtained from any one locality elsewhere in the world.
Professor Marsh has given a succinct account of the geology of the region in
the American Journal of Science for 1871, and in the succeeding volumes
brief descriptions of the many species and genera of extinct animals discoy-
ered by him.

In 1869 Professor Hayden, during his geological exploration of Wyoming,
also exainined the Green River Tertiary formations, and designated the more
superficial ones under the name of the: Bridger group. The fossils collected
from the latter were submitted to the examination of the writer, and are
briefly noticed in the Proceedings of the Academy for 1870, and likewise in
Professor Hayden’s reports of 1870 and 1871.

During the same and the succeeding years down to the present time, Drs.
Carter and Corson explored the buttes in the vicinity of Fort Bridger and
discovered many important fossils. Their collections from time to time were
transmitted to the author, and by far the greater number of the animals char-
acterized in the following paper are indicated from the specimens of these
collections. Most of them have also been briefly noticed in the later volumes
of the Proceedings of the Academy, and in Professor Hayden’s reports for
1870 and 1871.

I may further remark that during the last summer Professor Cope made
an extended exploration of the Green River basin, and obtained large collec-
tions of fossils, to a full account of which we look forward with much interest.

Fic. 14. Perforated elk-tusk; one of a number of similar specimens found together with a “teshoa”
and human bones which had fallen from an old Indian graye, at the edge of a butte, three miles from
Fort Bridger.

27

MAMMALIA.

Order Perissodactyla.

Hoofed quadrupeds, with functional toes in the hind feet, and often like-
wise in the fore feet, in uneven number. Arrangement of the constituent
lobes of the crowns of the molar teeth unsymmetrical. Femur with a third
trochanter. Astragalus with the fore part divided into two very unequal
articular facets.

PALZAZOSYOPS.

Among the most abundant and interesting of the mammalian remains from
the Bridger Tertiary group, which the writer has had the opportunity of
examining, are those of a genus of odd-toed pachyderms to which the above
name has been given. The specimens consist of fragments of jaws with teeth,
isolated teeth, small portions of other parts of the skull, articular ends of
the limb-bones, and some of the smaller bones of the feet.

The anatomical characters of the specimens indicate Palzeosyops to have
been more nearly related with the tapirs than to any other living animals.
The jaws were provided with nearly closed series of teeth in full number,
that is to say three incisors, a canine, four premolars, and three molars to each
side of both jaws. The canines are as well developed proportionately as in
ordinary carnivores, and would lead one to suspect that perhaps Paleosyops
used a mixed diet of meat and vegetables.

The genus was originally established in the Proceedings of the Academy

of Natural Sciences of Philadelphia for October, 1870, on specimens of teeth
discovered at Church Buttes, Wyoming, during Professor Hayden’s geological
exploration. Tt was subsequently indicated in Professor Hayden’s Prelimi-
nary Report of the United States Geological Survey of Wyoming, published in
the spring of 1871, and is there arranged among the artiodactyl or even-toed
pachyderms. Much additional material, comprising many parts of the skele-
ton of the same genus, having been received from Drs. Carter and Corson,
its characters were more fully ascertained, and its true position as a perisso-
dactyl or odd-toed pachyderm determined. 'The later account of these is given
in Professor Hayden’s Preliminary Report of the United States Geological
Survey-of Montana, &c., published in the spring of 1872.

Since then Professor O. C. Marsh has published a notice in the American
Journal of Science of August, 1872, of some remains ascribed to two genera

28

with the names of Paleeosyops and Limnohyus. From the notice it would
appear he has overlooked the description of Paleosyops in the report last
mentioned. He intimates the reference of the genus to the Perissodactyls as
if previously unknown, and suggests the reference of specimens to it in which
“the Jast upper molar has two inner cones,” though it is distinctly stated in
the above report that “the last upper molar of Palzosyops has but a single
lobe to the inner part of the crown.” Upon this character he founds the pro-
posed genus Limnohyus, which, under the circumstances, appears untenable ;
but if a pair of lobes to the inner part of the crown of the last molar be con-
sidered a distinctive generic character, the name might be transferred to the
genus possessing it. .

Thesskull of Palzosyops, and the same may be said of other parts of
the skeleton so far as they are known to us, approximates in form and
constitution those of its probably contemporaneous ally, the Palzotherinm
of the Eocene period of Europe. In both genera the skull presents a
broad, triangular forehead. In Palzosyops it is more prolonged posteriorly,
and is more abruptly curved forward to the root of the muzzle. In both the
temporal fosse are very capacious, indicating masticatory muscles approaching
in power those of the great carnivores. In Palzosyops they are separated by
a much shorter crest than in Palzotherium. In the former the muzzle is rather
abruptly prolonged forward from the base of the forehead ; in the latter the con-
vexity of the forehead is continued in the muzzle to the end of the nose. In
both genera the muzzle is broad, but in Palzosyops the nasals are longer and
project forward as much as the jaws. The lateral nasal notch is nearly alike in
both, but is longer in Palzeosyops. In both, the orbits are open behind, and are
defined from the temporal fossee by long, angular post-orbital processes. The
jaws nearly repeat one another in the two genera. The number of teeth,
their kind, relation, and general construction, are likewise the same. In
Palzosyops they form more unbroken series in the two jaws, as the hiatus
back of the canines, which is comparatively large in Palzeotherium, is very
trifling in extent in Palzosyops.

PALZOSYOPS PALUDOSUS.

The species Paleosyops paludosus was first indicated under this name in the
Proceedings of the Academy of Natural Sciences of Philadelphia in 1870, and
was founded on a number of isolated teeth and fragments of others obtained by
Professor Hayden at Church Buttes, Wyoming. Of the specimens, a last

29

upper premolar is represented in Fig. 5, Plate V; a fragment of a second
upper molar in Fig. 6, Plate XXIII, and two lower premolars and a molar
in Figs. 3 to 5, of the same plate. The teeth apparently all belonged to the
same individual, which had reached maturity, but had not advanced so far as
to have the summits of the tooth-lobes worn through so as to expose the
dentine. The enamel is longitudinally wrinkled on the sides of the true
molars and in a less degree on the premolars. ;

The last upper premolar (Fig. 5, Plate V) has a trilolate crown consisting
of an outer pair of acute pyramidal lobes, and an inner larger conical lobe
embraced by a basal ridge in front and behind.

The fragment of an upper molar (Fig. 6, Plate XXIII) consists of the fore
part of the crown, and is composed of an outer crescentoid pyramidal lobe

‘and an inner smaller conical lobe. A strong convex buttress forms the antero-
external angle of the crown, and a moderate basal ridge bounds it in front.
A conspicuous tubercle, the rudiment of an additional lobe, occupies the angu-
lar interval between the principal lobes and the basal ridge.

The lower molar tooth (Fig. 5) has a fore and aft bilobed crown as in
Palzotherium and Titanotherium. The lobes are crescentoid pyramidal, and
the anterior is the smaller. ;

The lower premolars have the same essential constitution as the true molar,
but are less well developed. In the fourth premolar (Fig. 4) the relative size
of the lobes is reversed, the anterior being the larger, and the postero-internal
buttress of the crown is obsolete. In the third premolar (Fig. 3) the poste-
rior lobe is still more reduced in size, the anterior lobe is proportionately
enlarged, and the inner buttresses of the crown are obsolete.

The measurements of the specimens are as follows:

Lines.
Fore and aft diameter of second upper molar, BSHERMEE Mee ee, ee ee 17
Pransverse diameter of second upper molar ........ .-...-2.. 2.0. ee eee cee ee. 18
Fore and aft diameter of last upper premolar............ 02-22. ..-.2-eeeee sees 94
Transverse diameter of last upper premolar .......-.....------.-.+--.--2---- 2
Koreand att diameter of second lower-molar. ..... --- 2.6 --..s062 22 ee eee 16
Drnsverse@iamezer of second lower molar.....-. ..---....-..---2---e0e----- 10
Korerandrari diameter of fourth) lower premolar. -.....-.-....--.-.---+-.----- 94
Poansversemdmerer On touUrtMlOwer premolar .-.....--.....2e2-+-0--4.5------ 64
Fore and aft diameter of third lower premolar.......-----.-.-..--.- Eicccu beget Si
Rranswerse diameter on thind lower premolar.......22-<6 22-0. 2--c.-+-+-5---- 5

Shortly after the original description of the above specimens, several others

30

were received from Professor Hayden, obtained on Henry’s Fork of Green
River, Wyoming, which are referred to in the last paragraph of the same
article of the Proceedings above mentioned as the former ones. The addi-
tional specimens consist of seyeral small jaw-fragments, with teeth, belonging
to an individual past maturity, as indicated by the worn condition of the
latter.

One of the specimens, a much-worn last upper premolar, is represented
in Fig. 4, Plate V. It agrees with the corresponding tooth above described
both in form and proportions. The summits of the three lobes of the crown
are worn down so as to expose large tracts of dentine.

A second specimen consists of an upper-jaw fragment retaining a portion
of the first molar and the complete second one. The former was so much
worn as to have a great part of the enameled triturating surface removed.
The second molar, represented in Figs. 8, 9, Plate V, has a.low trapezoidal
crown composed of four lobes, of which the anterior two agree in constitu-
tion and proportions with the fragment of the corresponding tooth above
described. The outer pair of lobes are crescentoid pyramidal and bounded
externally by strong convex buttresses. The inner lobes, of which the an-
terior is much the larger, form broad cones. A strong basal ridge bounds
the crown in front. The enamel is worn smooth and is abraded from the
summits of the outer lobes so as to expose broad dentinal tracts. The fore
and aft diameter of the crown of the second upper molar is 164 lines; its
transverse diameter is 18 lines. The remaining specimen consists of an
upper-jaw fragment containing the last molar, represented in Figs. 6, 7,
Plate V. The tooth is fractured and its parts somewhat dislocated, so as to
extend its breadth. It has the same constitution as the former tooth, except
that it has but a single internal lobe, which in great part is broken away in
the specimen.

Many more complete specimens referable to Paleosyops paludosus have
been received from Drs. Carter and Carson. One of the most important of
these consists of the facial portion of a skull containing nearly all the: molars
and the canines of both sides. The specimen submitted to my examination
by Dr. Carter, represented in Fig. 51, Plate XVIII, was discovered ina
greenish friable sandstone of the Grizzly Buttes. The face is entirely broken
away at ils upper part and fore extremity. The molar teeth, of which a full
series is represented in Figs. 3, 4, Plate IV, are for the most part preserved

ol

entire, but the canines, of which one is represented in Figs. 2, 3, are broken
off at the crown. ‘The specimen pertained to an individual past maturity, as
indicated by the worn condition of the teeth. The enamel is abraded from
the summits of the outer lobes of the last premolar and the molars and the
summits of the inner lobes of the*first molar, so as to expose tracts of den-
tine. Hlsewhere the enamel is worn smooth, but remains of its original
rugose condition are yet visible in the last molar. In anatomical character
and proportions the teeth agree in all respects with those corresponding
among the specimers above described.

The molar series consists of seven teeth which successively increase in
size from first to last. ‘The molars or true molars approach in character those
of Titanotherium, and in a less degree those of Anoplotherium and Chalico-
therium. The crown is broad and low and rather rhombic in outline. It is
composed of four principal lobes expanding in a common base. The outer
lobes are the larger and have the shape so common in many allied animals as
Paleeotherium, Anchitherium, Anoplotherium, Oreodon, Cervus, &c. They
are three-sided pyramids with crescentoid summits, the anterior extensions of
which form stout external buttresses to the crown. The inner lobes are
broad cones less prominent than the outer lobes. The anterior is the larger,
and is situated opposite the angular recess of the outer lobes; the posterior
occupies a position opposite the postero-internal face of the contiguous outer
lobe at the inner back corner of the crown.

A strong basal ridge occupies the fore part of the crown, and elements of
the same are found at the bottom of the outer faces of the external lobes. A
tubercle exists in the angular interval of the anterior lobes and the basal
ridge in front, which looks as if it were the rudiment of the large antero-in-
ternal lobe in Anoplotherium and its homologue in ordinary ruminants.

In the last molar the postero-internal lobe, as existing in the molars in.ad-
vance, is absent or is substituted by a small tubercle extending outwardly as a
posterior basal ridge to the crown.

In the unworn condition of the upper molars of Paleeosyops the external
lobes of the crown have acute crescentoid summits which conjoin on the sum-
mit of the median outer buttress. As the teeth were worn away in mastica-
tion, a W-shaped tract of dentine appeared on the outer lobes, and this gradu-
_ally widened with the progress of abrasion. As the summits of the inner
lobes were worn away, circular islets of dentine made their appearance,

32

which likewise gradually expanded as a result of mastication. A continuance
of the process would unite the inner and outer tracts, and in an advanced
condition of abrasion the distinction of the four lobes with the intervening
valleys would be obliterated, leaving a broad concave dentinal surface bordered
by the enamel at the sides of the crown. *

The upper molars of Palzosyops, while presenting considerable resemblance
to those of Paleeotherium, also exhibit well-marked differences. They differ
especially in the greater prominence and more robust character of the ex-
ternal buttresses of the outer lobes, in the form and more complete isolation
of the inner lobes, and in the absence of the deep pit at the termination of
the oblique valley of the crown.

In comparison with the upper molars of Anoplotherium, those of Palzo-
syops especially differ in having proportionately stouter buttresses to the.
crown externally; in possessing but a rudiment of the antero-internal lobe as
existing in the former, and in the different shape and relationship of position
of the postero-internal lobe, which in Anoplotherium has the form nee of
the contiguous outer lobe and embraces it as in the deer.

In comparison with the corresponding teeth of Chalicotherium, several im-
portant differences are observable. Of the outer buttresses of the crown in
this genus, the posterior is the larger, but in Palzosyops. the anterior is the
targer. The antero-internal lobe is proportionately less prominent, and the
postero-internal lobe has a different shape, being nearly like that in front of
it, and it is completely isolated. In Chalicotherium it is more like that in
Anoplotherium, and it joins the fore part of the postero-external lobe. In
the last molar of Palzosyops the postero-internal lobe is obsolete, but in
Chalicotherium is proportionately as weil developed as in the other molars.

As previously intimated, it is to the upper molars of Titanotherium that
those of Palzosyops have most resemblance. The abrupt and deep pit near
the centre of the crown is absent. ‘The rudimental lobe at the fore part of
the crown between the anterior principal lobes is proportionately less de-
veloped, and yet is more isolated from the basal ridge. In the last molar the
postero-internal lobe is nearly suppressed, while in Titanotherium it is still a
conspicuous element of the crown, though less well developed than in the
other molars.

The premolars of Paleeosyops undergo a successive reduction forward and

assume a more and more elemental condition.

33

The fourth premolar has an oblong square crown with the transverse

diameter exceeding that fore and aft, and with the inner part nearly semi-
circular. The crown is composed of three lobes, corresponding with the
outer pair of the molars, and apparently the large inner one situated opposite
the recess of the former. The outer lobes are like those of the molars, with
the back one proportionately less well developed, with the outer median but-
tress of the crown suppressed, and with the outer median fold of the antero-
external lobe more prominent. The inner lobe is a singie, broad, undivided
cone less prominent but rather larger than the outer ones. It appears to be
homologous alone with the anterior of the inner cones of the molars, and at
least does not appear to be a connate pair as in the corresponding tooth of
Titanotherium. The conspicuous pit in the center of the crown in this
genus is absent in Paleosyops. A thin basal ridge starting in front and back
of the internal lobe festoons the crown outwardly and at the bottom externally
of the outer lobes.
_ The third premolar is a diminished representative of the one behind, but
has its antero-external lobe proportionately a little larger, and the postero-
external lobe proportionately reduced. The teeth of the two sides are not
symmetrical in the specimen. That opposite to the one represented in the
figure has its fore part broken away, but the postero-external lobe is consider-
ably longer than in the entire tooth.

The second premolar has a trihedral crown, in which but two lobes are
conspicuous. In comparison with the premolars behind, the internal lobe is
greatly reduced in size, and the antero-external lobe is much enlarged so as to
become the main portion of the crown, while the postero-external lobe is ob-
solete.

The first premolar is a small tooth separated from the others by a slight
interval. It has a simple short conical crown with the base slightly extended
backward, and is inserted by a pair of fangs. The other premolars and the
molars are inserted with three fangs, of which the inner one in the latter
teeth consists of a connate pair.

The canine teeth of Paleeosyops were powerful and efficient weapons, and
resembled those of ordinary carnivores more than they do those of nearly
allied living animals. Though imperfect in the specimen under consideration,
the remaining portions, as represented in Figs. 2, 3, Plate IV, indicate teeth
of the form and proportions of those of living bears. They also appear to

have nearly the same relative position with the other teeth and the same
Fy x
5 G

34

direction as in the latter. The fang is robust and gibbous, and comes from
the alveolus in a direction downward and forward with a greater degree of
divergence than usual among carnivora. The face of Paleosyops, judging
from the imperfect specimen, a side-view of which is given in Fig. 51, Plate
XVIII, in its complete condition, would appear to resemble in shape that of
the Elotherium of White River, Dakota, except that the muzzle was pro-
portionately shorter. Among living animals, it appears to have resembled
that of the bears more than in those nearly related to it. The zygomatic
arches are of robust proportions and widely divergent at their anterior attach-
ment to the face. The malar portion of the zygoma is divided by an acute
ridge curving from the anterior orbital margin outward, downward, and back-
ward. The surface above this ridge curves outwardly and downward from
the floor of the orbit continuously. The surface beneath is a broad trilateral
plane looking forward, downward, and outward, and is roughened for the at-
tachment of a powerful masseter muscle. The space behind the anterior
abutment of the zygoma indicates a temporal fossa of large capacity.

The orbit appears low, and is directed obliquely forward and outward.
In advance of the prominent antorbital margin the side of the face is nearly
vertical. The infra-orbital foramen is rather large, and is situated over the
position of the last premolar. In front of the foramen begins the swell of the
large canine alveolus, and below its position is the alveolar border, marked by
the vertical ridges of the molar fangs. The hard palate is well arched, and
nearly parallel at the sides. Its surface in the specimen is obscured by the
attachment of rocky matrix. The breadth of the face at the zygomata
appears to have about equaled the length. )

The measurements of the specimen are as follows:
Inches. Lines.

Breadth of face at zygomata on line with middle of last molars......-.-...- 7 8
Breadth, of face outside of lastimolars: =.5-52 5-2-2. 025 oso 2 ae ee eee 4 6
Breddth of face outside of canine alveoli ...... .. 2.22.55. 52224) -<5- 250 3 6
Breadth of face at infra-orbital foramina 2... & 222.224.232.542 35-5 222. <j aaa 2
Breadth-of hard palate between lastmolars) 22-22 s-ses5->. seo ee aoe 1 a
Breadth of hard palate between last premolars. .- --- BOE Coe ee cee at 5)
Distance from back of last molar to fore part of canine........-.-..-- Le 8

For comparison, the measurements of the teeth will be given after the
description of the follcwing series.

Some additional’ specimens, which I suppose to belong to Paleéosyops
paludosus, notwithstanding certain differences hereafter to be mentioned, con-

35

sist of most of the upper teeth, with small attached jaw-fragments, obtained
by Dr. Carter on Henry’s Fork of Green River. Of these specimens a com-
plete series of nearly perfect molar teeth is represented in Figs. 5, 6, Plate
IV. The teeth in their abraded condition indicate an older animal than that
_ to which the facial specimen above described belonged. The summits of the
constituent lobes of the teeth are nearly all worn to such a degree as to
exhibit tracts of dentine, and the enamel is everywhere smooth, except on
the external faces of the outer lobes near the basal ridge.

The molars are almost identical in character with those above described
in the facial specimen. Trifling differences consist in the less production of
the median fold on the outer face of the external lobes, and perhaps the less
degree of prominence of the tubercle in the interval anteriorly of the anterior
pair of lobes. The last premolar is likewise identical with those above
described, except that its crown is rather more square, or is not quite so
wide. The anterior three premolars depart considerably from their character
in the facial specimen, and their differences may probably indicate a different
species. The third premolar is a diminished representative of the one behind
it, the three lobes of the crown holding nearly the same proportionate devel-
opment; whereas in the corresponding tooth of the facial specimen the pos-
tero-external lobe is considerably reduced in its proportions. In the second
premolar.the crown still retains a postero-external lobe reduced in proportion
to the others, but in the corresponding tooth above described it is obsolete.
The retention of this lobe gives the crown a greater fore and aft breadth than
that contained in the facial specimen. ‘The first premolar has the same form
as that of the latter, but it is much larger.

The mutilated canine, accompanying the molars first described, is repre-
sented in Fig. 1, Plate IV, and is but little more than half the size of those
contained in the facial specimen.

An isolated incisor, represented in Fig. 8, accompanying the molars and
canine just described, is regarded as an upper one. The crown is mutilated,
but when complete appears to have had a short, conical crown, bounded
behind by a strong basal ridge. The fang is laterally compressed, and is
about an inch in length. :

Comparative measurements of the series of teeth of the two individuals of
Palaosyops, indicated by the facial specimen, with teeth, from Grizzly Buttes,

36

and the specimens of teeth from Henry’s Fork, just described, are as

follows :
Lines. | Lines.
Space occupied by the entire molar series -.....-....-...-.22------+-- 69 71
Space occupied by the true molar seriéS 0 9. ns se oe 41 41
Space oeeupied by the premolar series -.-2--.--- 0-2-2 -n one pees 28 32
Antero- Antero-
posterior. Transverse. posterior. Transverse.
Lines. Lines, Lines. Lines.
Diameter of first. premolar ....-...-.--.-... o 3 7 t
Diameter of second premolar ...-..--------- 6 7 8 a
Diameter of third premolar.........---.--.. i 8 8 9
Diameter of fourth premolar .--. -....-.-.-- 10 105 8 10
Diameter oirstpmolan 2s ee ciaeeeee a eee - 12 13 12 124
Diameter of second molar ............------ 16 ly 15 16
Diameter of last molar... -.-.- fdr oe ers 17 184 17 164
Lines. | Lines.
Length of fang of upper canines...... --.-- Nah 2 ANS pli le e 28 18
Antero-postenor diameter of camies=.-2= asses ees eer eee 123 74
Transverse diameter of canines......-----.---.-.---+----+--+-------- 103 7

The question arises whether the differences which have been indicated in
the premolars and canines of the two different series of teeth above described
indicate more than one species. The differences are clearly in degree of
development and size, and these may probably be of a sexual character. The
individual with the more powerful canines I suppose to have been a male, in
which, with a greater proportionate degree of development of these organs
than in the female, there appears to have been a reduction in the degree of
development of the anterior premolars.

Another specimen submitted to my examination by Dr. Carter, and repre-
sented in Figs. 6, 7, Plate XXIV, belonged to an older animal than the
former, as indicated by the more worn condition of the teeth. The latter
consist of the anterior three premolars and a portion of the fang of the canine,
and they have the same form and proportions as the corresponding teeth
above described. The first premolar is close to the others, or is not sepa-

od

rated by a conspicuous interval as in the former specimen. The lobes of the
second and third premolars are worn nearly to a level with their base. The
outer surface of the maxillary, as seen in Fig. 6, is defined by an oblique
ridge at the nasal border, within which the suture of the premaxillary pur-
sues its course over the position of the fang of the canine. Just outside of
the nasal border the surface of the maxillary is depressed.

The measurements of the specimen are as follows:

Lines
Space occupied by the anterior three premolars..........-..-. ..-.-....- ree MS CAE
Antero-posterior diameter of first premolar..........-..----.-.+-.--.---. oe OR
ironswerse diameter on first premolar. ...--..-<-. 5.22222 ---200 2 =e seen eee eee of
Antero-posterior diameter of second premolar....:-.--.-.---.--..-----.----..-- 7
iraimsyerse diameter Of Second premolar. .......--.-:----.--.--.-.----------, 63
Antero-posterior diameter of third premolar.............- oe MMB og £4 30. eR 8
Gransverse diameter of third premolar: ..--.-.....5../.-.2.-- -2,--2.-- 9
Parma CUM AT OMCAMING: 0. oe ci o-+ cent e ven dldw ces deces te ewes less sete ks 8

Fragments of half a dozen lower jaws referable to Palzosyops, collected in
various localities in the vicinity of Fort Bridger by Drs. Carter and Corson,
have been submitted to my examination.

A well-preserved specimen, consisting of the greater part of the jaw, was
discovered by Dr. Carter imbedded in a greenish gravel thirteen miles south-
east of Fort Bridger. The right ramus is represented in Fig. 11, Plate V, and
it contains the molars and the back two premolars, which are also repre-
sented with a view of the triturating surfaces in Fig. 10 of the same plate.
The teeth, corresponding with those in part upon which the species Paleo-
syops paludosus was originally indicated, are identical in anatomical character
and so nearly in size that the jaw may be regarded as pertaining to the same
species.

In advance of the teeth retained in the jaw there are indications of two
additional premolars verging close upon the remains of the canine alveolus,
and thus the specimen shows that the number of the lower molar series of
Palzeosyops is seven.

The lower molars of Palzosyops resemble those of Palzeotherium and
Anchitherium, but even more closely those of Titanotherium. The crowns
are proportionately wider and lower, or appear more robust than in the former
genera.

The crown of the anterior two molars is quadrately oblong oval, with the
fore and aft diameter largest and the depth less than the width. It is com-
posed of two divisions or lobes, one in advance of the other. The last molar

38

has the same form and construction, with the addition of a third but smaller
lobe. ’

In the unworn molars the principal constituent lobes present acute cres-
centoid summits embracing a concavity which opens to its bottom by an
angular notch on the inner side of the crown. The contiguous arms of the
crescentoid summits conjoin in a strong conical eminence situated just in
advance of the middle of the crown internally. The point of this eminence
is simple or undivided; in Anchitherium it is deeply indented and appears to
be composed of a connate pair of eminences.

The fore part of the summit of the anterior lobe in Palzeosyops curves
downward and inward, and ends in a slight prominence at the anterior inner
corner of the crown. The hind part of the summit of the posterior lobe ends
in a prominence like that in advance, but smaller, and situated at the postero-
internal corner of the crown.

Externally the lobes of the crown are angularly convex, and include deep
angular recesses sloping outwardly and downward, and bounded by festooned
elements of a basal ridge. The inner surface of the crown is nearly vertical,
smooth, and without a basal ridge. The latter is especially well developed
at the fore and back part of the crown, except in the last molar, in which the
additional lobe takes its place. This lobe is a much reduced likeness of those
in advance, with the arms of its crescentoid summit contracted and conjoined
with the posterior conical eminence of the crown internally.

The molars undergo a rapid reduction forward, and they are inserted by
two fangs. The crown of the last premolar is a reduced representative of
that of the succeeding molar, with the posterior lobe proportionately, in
comparison with the anterior lobe, less well developed. In the crown of the
third premolar there has been a further proportionate reduction in the back
lobe, but the anterior remains nearly the same, except that it appears more
robust from its connation with the homologue of the anterior of the inner
conical eminences of the teeth behind.

In Palzotherium and Anchitherium the corresponding premolars with those
described repeat the form of those of the molars, and in this respect greatly
differ from Palzosyops. The inferior premolars of Titanotherium in a perfect
condition are not sufficiently well known to institwse a comparison with those
of Palzeosyops. |

The lower molars of Paleosyops in wearing would assume the same

39

appearance as those of Palesotherium and Anchitherium at the same stages of
attrition. ; :

The space occupied by the entire molar series is estimated at about 64
inches, of which the true molars occupy rather less than 4 inches.

The measurements of the molar teeth contained in the lower jaw are as

follows :
Antero- |
& posterior. Transverse.
} Lines. |} Lines.
Micmeheron tind puemolar .-:.--.- 22. ys -6--2e------------- 84 54
icmieremoLtourtm premolar ...-.--2--2------ 22+ + eben eee ee 9 64
PEE Lem Om MTSU MNOLAIN .— - oo =a 6)2 12 ee Bee ee ed oslo eee 123 8
Pre HOI OM SECON IMOLAN: . [2 <)2)-. ofS aise 2-2 = siete oe == a aa 94
SEDMMMeteiOmlash TOMA <2 2262-2 scence cn nent mong eee cee: toe 10

The premolars are inserted by a pair of fangs, except the first, which has

but a single fang.

The lower jaw of Palzosyops, as seen in Fig. 11, Plate V, approximates in
form that of the tapir and hog, though presenting important differences.
The dentary portion of the ramus is proportionately shorter and deeper than
in either of those animals, and the alveolar border is more ascending poste-
riorly.. The base is more convex fore and aft than in the hog but less than
in the tapir, and is more obtuse than in either. The outer surface is vertical,
with a slight outward slope at the fore part.

The back part of the jaw is of more uniform breadth than in the tapir, and
is more like that in the hog. Toward the angle the outer surface is a verti-
cal plane, with the lower border or base more directed downwardly than in
the hog. The upper or ascending portion presents a masseteric fossa about
as deep as in the tapir but of considerably greater width.

The condyle is large and-thick, and much like that in the tapir, but is less
inclined inwardly. It has about the same proportionate elevation above the
level of the base of the jaw, but less above the level of the teeth.

The border of the jaw below the condyle behind is at first slightly concave
and then convex, as in the hog, but to a less degree. The coronoid process
is about as long as that of the tapir, but the fore part curves upward and
backward without any inclination forward. The notch behind hardly descends

below the level of the condyle.

40

The mental foramen is smaller than in the tapir, and is situated below the
interval of the second and third premolars.

The length of the lower jaw, from its back border to the fore part of the
second premolar, is 9% inches, and in the complete condition it measured
about 2 inches more.

Portions of several lower jaws, apparently all referable to Paleeosyops, were
obtained by Dr. Corson at Grizzly Buttes. The specimens exhibit some
variation in character, and may, perhaps, belong to more than one species of
the genus. One of the specimens consists of a dentary fragment containing
the true molars and the fangs of the two premolars in advance. ‘The retained
teeth are like those previously described, but are in a trifling degree smaller.
The series measures 3% inches. The jaw-fragment nearly agrees with the
corresponding pcrtion of the specimen above described, but is of more uniform
depth. 1

Another specimen consists of a right ramus, without the chin and back
part, and broken into three pieces. It contains the fang of the canine and
most of those of the molars. The jaw is of more uniform depth below the
position of the teeth than in the more complete specimen first described, and
more robust than in either of the former specimens. The retained portion
of the fang of the canine indicates a larger tooth than existed in the first-
described specimen—one, also, that would accord in its robust character with
those of the facial specimen referred to Paleosyops paludosus. ‘The presence
of the fang of the canine produces a strong bulge at the side of the chin,
which appears to have been comparatively feeble in the first-deseribed speci-
men. ‘Two mental foramina are situated below the position of the second
and third premolars. ‘The first premolar appears to have had a single fang
consisting of a connate pair. It was separated from the canine and second
premolar by conspicuous intervals, the posterior of which is the larger. A
portion of the chin being retained in the specimen, it would appear in the
entire condition to form a-broad slope defined at the sides by the conyexities
of the canine alveoli. ‘The rami were completely co-ossified at the symphysis
without the suture of union being apparent.

The remaining specimen consists of a portion of the jaw containing the
fangs of the last two molars, and the portion immediately behind extending
toward the angle. The dentary portion of the bone is considerably deeper

than in the corresponding portion of the preceding specimens. Tbe base

41

below the position of the last molar tooth is rather more conspicuously tuber-
ous and roughened for muscular attachment, and the concavity back of this
is more posterior and deeper than in the first-described specimen.

Comparative measurements of the lower-jaw specimens, including the one
first described, are as follows :

|
| No. 1. | No. 2: | No. 3. | No. 4.
|

Tines. | Dines. | Lines. | Lines.

Space occupied, by the entire molar series.--.-....--..-.-.|.--.--| .-.--|------ 78
Space occupied by the molars and last two premolars. - --. 64 65 60 62
Space occupied by the-true molars .-.. .-..----..--...-- 46 48 45 45
Distance from last molar to back of jaw.-......-.....-..-- 49 A lie te oil, 5
Width of ramus back of condyle .........-- aa ee 44 Sat legedeaeiis (Eyal ties
Depth of ramus at middle of last molar -............-...- 31 32 33 33
Depth of ramus below last premolar ....-...-.--...-. rectal pe 23 26 29
Thickness of base below second molar .........- «....-.. 13 11 12 13
_Antero-posterior diameter of last molar............ ....- 19 20 19 19

A small fragment of the chin of a lower jaw, referable to Palsosyops,
retains part of the alveolus of a large canine, and portions of the fangs of
three incisors of the same side, thus indicating the number of the latter teeth
in the animal. The canine alveolus has been about an inch in diameter. In
the ramus of the jaw above described, retaining the fang of a canine, this
tooth has been nearly in proportionate size to that of the alveolus just men-
tioned.

Small fragments from three different skulls, attributable to Paleeosyops,
consisting of portions of two sagittal crests and the supra-occipital, indicate
capacious temporal fosse, separated by a short, thick crest and a broad
occiput. ;

The fragments of: sagittal crests are from the fore part, retaining the suture
and notch for the summit of the frontal. The upper surface of the crest is a
flat triangle, slightly depressed at the middle, with the notch for the frontal
in its base. In the latter position it is 14 inches wide; and a couple of inches
back of this position the crest is # of an inch thick.

The occipital fragment on each side in front presents a wide, sloping sur-
face, which contributes to the temporal fossa. The posterior surface in
general appearance resembles that in the rhinoceros. The upper portion
forms a broad, even concavity, undivided by any trace of a vertical ridge, and

6G

42

only roughened at the summit for the attachment of the nuchal ligament.
The lateral processes are angular and divergent, and the space between them
is 44 inches in-width. The lower portion of the occipital surface approaching
the occipital foramen is convex. The height of the occiput from the latter is
about 4% inches.

A lumbar vertebra was found by Dr. Corson at Grizzly Buttes. It pre-
sents the ordinary ungulate form. The body is 2 inches long, but some-
what shortened below. It is concave fore and aft, at the sides, and beneath,
where it is also slightly carinate. The anterior extremity is slightly convex,
14 inches transversely, and a little less in depth to the prominence beneath.
The posterior surface is flat, or feebly depressed. The transverse process
springs from the upper level of the body. A well-developed metapophysis
projects from the position of the anterior zygapophysis. The diameter of the
spinal canal is about an inch.

Besides the skull-fragments and vertebra of Palzeosyops, a number of
isolated carpal and tarsal bones, and many fragments of the long bones and
other portions of the skeleton have been collected by Dr. Carter, Dr. Corson,
and Professor Hayden’s party. Many of the bones had been fractured, or
more or less crushed, while they lay in their bed, and many have been further
injured after exposure through the influence of the weather and other causes.
The bones nearly resemble in size and construction the corresponding ones
of the American tapir.

The distal extremity of a humerus, represented in Fig. 3, Plate XIX, was
found by Dr. Corson in the vicinity of Fort Bridger. The breadth of the
specimen between the supra-condyloid eminences is 34 inches. A deep
supra-condyloid fossa occupies the front of the humerus, opposed to the
deeper and more capacious olecranon fossa. The articular trochlea is 24
inches wide in front, and narrows an inch less behind.

A mutilated femur, without the head and trochanters, represented in Fig. 1,
Plate XIX, was obtained on Henry’s Fork, of Green River, by Dr. Carter.
In its complete condition it has approximated 15 inches in length. The
shaft is three-sided, and at the middle is 16 lines in diameter from before
backward, and 19 lines transversely. The median trochanter projects from
the outer border of the prismoid shaft, and is higher up in position than in
the tapir. The distal extremity resembles the corresponding part in the
latter, but the trochlea for the patella is of less breadth.

43

Fig. 2, Plate XIX, represents a much better preserved distal extremity of
the femur than that of the former. It was obtained by Professor Hayden’s
party at Grizzly Buttes. At the supra-condyloid eminences it is 34 inches
in diameter. The width at the condyles is 22 inches. The trochlea for the
patella, where widest, measures 16 lines.

The detached head of a femur, in perfect condition, found by Dr. Carter
near Fort Bridger, measures about 2 inches in diameter. A deep cup-like
pit for the round ligament approaches the center of the head much more
closely than in the tapir.

A nearly entire femur of Paleeosyops, received from Dr. Carter since the
above was written, is represented in Fig. 5, Plate XXIX. It nearly repeats
the form of that of the tapir, but rather resembles that of the Indian tapir,
or Baird’s tapir, of Guatemala, than that of the American tapir. In compari-
son with that of the Yapirus Bairdi, it is rather larger, and the upper
. extremity is proportionately somewhat wider. ‘The inner trochanter is
longer or more prominent, but the third trochanter is neither so long nor so
hook-like.

The measurements of the specimen are as follows :

Inches
Length externally from summit of great trochanter .-....-....-..---.--- re cea 25
Wiinneoenween head and ereat trochanter.....-.....-- --.--..-.2-----02--- 43
ePaen beer ME ORUTOC MANDO a mei = a we fenie cio nes een ee coe ee eee 23
ae ee ee Ae aS ieee iain alga wh cai ale se «manly eis’ Sle aces 21
iameserrore and att of shaft at middle ...........-..--2-. -. es--00--- gh? lek
es ie TELUS 0 ea Se A 2 EE A ee re 34

Fig. 1, Plate XX, represents a nearly entire tibia, obtained by Professor
Hayden’s party at Grizzly Buttes. The upper condyles are in some degree
pressed toward each other, and the extremity of the internal malleolus is
broken off. The bone is not quite so long as that of a tapir with which it
was compared, but is somewhat stouter. The tuberosity for the ligament of
the patella is of more robust proportions, and extends lower on the shaft than
in the tapir. The ridge descending from it is thicker than in the latter—
straighter, and is obtusely rounded. The length of the tibia is 9 inches; the
breadth of its distal end over 2 inches.

Fig. 2, Plate XX, represents a calcaneum, obtained by Dr. Corson near
the stage-route at the crossing of Smith’s Fork of Green River. It is nearly
like that of the tapir, but is stouter in proportion to its length. The tuber-
osity of the calcaneum is less compressed and is more obtuse in front. The

44

sustentaculum is of much greater extent vertically, and sustains a long ellipti-
cal facet for the astragalus. The anterior articular facet for the latter is of
much less extent than in the tapir, and is more distinctly separated from it
by the interosseous sinus. The articulation for the cuboid is of greater depth
but less width than in the tapir.

The extreme length of the calcaneum is 44 inches. The length of the
tuberosity is nearly 8 inches. The breadth of the anterior extremity of the
bone is 24 inches. t

Of two additional calcanea obtained by Dr. Carter, one was found on
Henry’s Fork of Green River; the other near Millersville.

Fig. 3, Plate XX, represents an astragalus found by Dr. Carter at the
bluffs, three miles from Millersville. The trochlea for the tibia is of less ex-
tent fore and aft than in the tapir; and the anterior extremity of the bone is
of less width but greater depth. The length of the astragalus is 2 inches;
the breadth of the trochlea twenty lines; the breadth of the anterior ex- .
tremity is the same, and its thickness is an inch.

Another astragalus, slightly larger, was obtained by Professor Hayden’s
party at Church Buttes. .

Fig. 4, Plate XX, represents three tarsal bones obtained by Professor Hay-
den’s party at Church Buttes. They pertained to the same individual, and
consist of the cuboid, scaphoid, and the outer cuneiform.

The cuboid is more cubical and stouter than in the tapir. The upper
surface is more regularly square and nearly a third wider than in that animal.
The articular facet for the caleaneum has about the same depth, but is nearly
twice the width. The facet for the first metatarsal bone is also of equal
depth, but a third greater in width,

The scaphoid is of rather less breadth than in the tapir, nearly of equal
depth, but not quite so thick. The articular facet for the astragalus is of
about the same extent, less breadth, but proportionately more uniform depth,
and it is less concave. The articular facet for the outer cuneiform is of about
the same depth, but of much less breadth than in the tapir. The facets for
the inner two cuneiforms have about the same extent as in the latter.

The external cuneiform is about the same depth as in the tapir, but of con-
siderable less breadth and of greater thickness.

The metatarsal articular facets of the cuboid and external cuneiform ap-
pear to indicate that the outer toe of Palzosyops was as large as the middle

45

toe, and that this was much smaller than in the tapir. This appears to be
confirmed by the specimen represented in Fig. 5, Plate XX, which I suppose
to be a middle metatarsal of Palzosyops. It was found by Dr. Corson in
the vicinity of Fort Bridger. It resembles the correspondibng one of the
tapir, but is shorter and of more slender proportions. It has about the size
of the lateral metatarsals of the tapir. |

Figs. 6 and 7, Plate XX, represent a first and second phalanx, probably of
Paleosyops. * The specimen of the first was obtained by Dr. Carter on Henry’s
Fork of Green River; the specimen of the second was found ‘near Fort
Bridger.

A specimen of a metacarpal, which I suppose to belong to Paleosyops,
was obtained by Dr. Corson at Grizzly Buttes. It has about the same length
as the middle metatarsal attributed to Paleeosyops, but is somewhat wider.
If it corresponds with the second of the series of four toes of the fore foot
_of the tapir, it exhibits a corresponding reduction in relation with the con-
tiguous toes that the middle metatarsal does to the others of the hind foot.

PALZOSYOPS MAJOR.

A larger species of Paleosyops is apparently indicated by some fragments
of large bones obtained by Dr. Carter at Grizzly Buttes and other localities
in the vicinity of Fort Bridger. Several of the specimens consist of portions
of limb-bones, but too much mutilated either for description or representa-
tion. Even the best specimen, consisting of a fragment of the lower jaw, rep-
resented in Fig. 8, Plate XX, is barely more than sufficient to render it
probable that it pertained to Paleeosyops. The jaw-specimen is furthermore
in some degree abnormal in form, due to inflammation or some other affection
connected with the second molar tooth. The bone outside the position of
the latter is much swollen, and the alveolar border is hollowed out and irregu-
lar. ‘The alveolus is also filled with the clay matrix, so that the tooth was
perhaps lost before the death of the animal. In its proportions, the jaw, in a
normal condition, would appear to be of more robust character than in
Palaosyops paludosus. In its present state, the hbase is more convex fore and
aft than in the latter, and the alveolar border more ascending posteriorly.

The remains of the molar fangs at the entrance of the alveoli appear to
indicate teeth of the same form and construction as in Paléosyops paludosus,

46

for which reason the fragment was referred to the same genus. The true
molars appear to have occupied a space of 4% inches, though this is probably
somewhat exaggerated, as the interval occupied by the last intermediate molar
appears proportionately somewhat too large. The crown of the last molar,
which was clearly trilobate as in Paleosyops paludosus, had an antero-posterior
diameter of 2 inches.

The former existence of a larger species than Palgzosyops paludosus, and
probably the same as that indicated under the name at the head of the present
chapter, is apparently confirmed by more characteristic materials placed at
my disposal by Dr. Carter in my recent visit to Fort Bridger. One of the
best preserved specimens consists of the greater part of the left ramus of the
lower jaw, containing six molar teeth, as seen in Fig. 1, Plate XXIII. The
jaw 1s considerably more robust than in those referred to Palzosyops paludosus,
though not to the degree I supposed from a view of the diseased specimen
above described. At the side it is more rounded toward the base, and is more
convex in a curving line from the root of the coronoid process beneath the
true molars, and is more bent inward and convex from the position just indci-
cated toward the technical angle of the bone. MRugosities of the surface in
several positions indicate stronger attachment of the soft parts, in accordance
with the greater bulk of the animal, than in Paleosyops paludosus.

The true molars have the same form and proportions as in the species just
named. ‘rifling differences appear to be dependent only on a difference in
the robust character of the species. The external basal ridge is slightly bet-

‘ter developed, as is also the case with the median ridge, descending on the
inner slope of the external lobes of the crown. The back lobe of the last
molar is also rather better developed, and incloses a shallower fossa on its
inner side.

The first premolar, situated immediately behind the canine, is inserted by
asingle fang, and is separated from the second premolar by a hiatus about a
third of an inch in extent. Below the hiatus, the jaw externally presents a
small concavity.

The last premolar has the same form as that in the jaw referred to
Paleosyops paludosus, though, from its worn condition, it looks different. In-
dependent of this, it exhibits no difference except that the base in advance

of the anterior lobe is produced externally in a strong ridge.

47

The third premolar also is like that of Paleosyops paludosus, excepting that
it exhibits a‘tendency to the production of a basal ridge not evident in
the former.

The second premolar, not present in the jaw-specimen of Paleosyops
paludosus, is a reduced form of the tooth behind it. A portion of the canine
alveolus retained in the specimen indicates a tooth of moderate size in com-
parison with the size of the jaw itself.

Another*series of lower molar teeth, attached to small jaw-fragments, and

represented in Fig. 2, Plate XXIII, also appear to me to be referable to
Paleosyops maor notwithstanding certain differences presentéd by the pre-
molars. he teeth are considerably more worn than in the preceding speci-
men; most of the summits of the constituent lobes of the crown of the mo-
lars and last premolar being so worn as to exhibit islets of exposed dentine.
The second molar is most worn, and presents on the summits of the outer or
principal lobes broad, depressed, shield-shaped tracts of dentine.

The molars have the same constitution as in the preceding specimen. The
last one is smaller, but the others are nearly of the same size, except that the
first one is thicker, especially at its fore part, and is therefore of more uniform
diameter. The basal ridge of the anterior two molars is better developed
externally than in the former specimen. In the first molar the anterior lobe,
being proportionately rather better developed than in the corresponding tooth
of the previous specimen, its anterior ridge curving inwardly, is stronger, and
it embraces a more conspicuous fossa.

The last premolar differs somewhat in proportions from that of the former
specimen, but is otherwise nearly the same, except so far as it is altered in
appearance from being more worn. It is of less breadth fore and aft, and
is thicker, and it does not present the ridge at the fore part of the base,
externally, of the anterior lobe, being in this respect more like the corre-
sponding tooth in the jaw-specimen of Paleosyops paludosus.

The third premolar differs from that of the former specimen very much in
the same manner as the succeeding tooth. The crown is of less breadth fore
and aft, and is thicker. It has exactly the same constitution, but looks differ-
ent on account of its more worn condition, its difference of proportion, and
from the absence of a basal ridge occupying the fore part of the crown, exter-
nally, in the former specimen.

Comparative measurements of the teeth and jaws of the specimens just

4%

referred to Pa/e@osyops magor, and the jaw-specimen, with teeth, of P. palu-

dosus, are as follows :

Paliosyops | Palzosyops

major. paludosus.
Lines. | Lines. Lines.
Depth of jaw at middle of last molar ........-.........-.... Sf fae gee 32
Depth of jaw at middle of last premolar......-. sis Brot ts hate Ree 26 o)euaree 23
Thickness of jaw below interval of last two molars....-...--- 16; hoe 13
Thickness of jaw below third premolar..-.........-.-......- pe pee 2 104
Distance from canine alveolus to back of last molar..-... Des i Oe eee 3 277
Length of the complete molar series..........-.-----.---..- | 90 |: cee
Length of the molar series, excluding the first premolar. .-..-. 82) 2). =the
Length of the molar series, excluding the first two premolars.| 72 68 64 |
Leneth ofthe premolarisenies--25-- 222. aS (eee eee fe a Pea es ee
Length of the true molar series. - -.. 210 HO) SR ae ae 53 51 465
Breadth of second premolar..........-.... were okies async ceuotage 9. |... soe
Dhickness ofysecond: premolar. sc. sacs tele eee le oe B | 2. eee
Breadth ot thirdapremolar eee eee eee Neia oer oem 83 8 84
Thicknessiofthind premolars es 2) er elle eee eee 53 6 54
Breadthvor founthyprem Olan 5 gy: eras) ere ee 94 83 9
Tiiekness or fourth premolars ccc a2 ee see eee ee eee a (Ps 64
Breadthror first molar.(e2 22 od. 2 2e. oat ee aa ee foe cokes oer 13$ | 134 123
Thickness of first molar 42.....222-2-=% Sieh Sr aeen Seeeties o Ges naacs eeu te 94 8
Breadthvotsecond molare. 2... janes -esecaee ee tae 164.) . 16 |) iis
JUMOIGSS OL SOCO NG! MOM Jey eb oscwasdasscebss seoosecsa: 102 | 103 95
BreadthvofithirdSmolara: > la tae een eee ee ee 24 22 19
Thickness of hind molar Aes vee ete cee eee See 134 | 12 10

Some additional specimens, found by Dr. Corson in the buttes of Dry
Creek Canon, appear to belong to the larger Palzeosyops. These consist of
some upper teeth, comprising a canine, a second and last premolar, and the
second and third molars.

The latter are represented in Figs 10, 11, Plate X XIII, and they agree .
in character with the corresponding smaller teeth described under the head
of Paleosyops paludosus. They are but slightly worn at the summits of the
lobes of the crown, and the enamel is conspicuously wrinkled.

The last premolar, represented in Fig. 9, of the same plate, likewise agrees
with the corresponding tooth described under the head of Pal@osyops palu-
dosus, except that it is of larger size. The tooth is but slightly worn, and
exhibits a much less wrinkled condition of the enamel than the true molars.

The second premolar, represented in Fig. 8, resembles in form that of the

second series of specimens of upper molar teeth, described under the head of

49

Paleosyops paludosus. It is larger, less worn, and has, comparatively with
the true molars, smooth enamel.

An upper canine tooth, represented in Fig. 7, is of less size than that in
' the facial specimen of Paleosyops paludosus, the reverse of the condition in
this respect of the molar teeth. The canine tooth resembles, in its form and
proportions, the corresponding weapon of the bear. The crown is of mod-
erate length, and curved conical. It is provided with a subacute ridge in
front and behind, defining the smaller inner face from the outer one, and has
the base slightly thickened internally. ‘The enamel is nearly smooth, and is
somewhat worn.on the anterior face. The fang is considerably longer than
the crown, less curved, and is in some degree gibbous.

A lateral incisor, represented in Fig. 5, Plate XXIV, is a strong tooth,
somewhat resembling that of the tapir. The crown is conical, with the inner
and otiter faces defined by ridges, with the base thickened in front, and a
strong basal ridge internally. The fang is about twice the length of the
crown, and is somewhat sigmoid.

The measurements of the upper teeth of Palzosyops maor, in comparison
with those of P. paludosus, are as follows:

| Palieosyops| Palzeosyops
major. | paludosus.
: : Lines. Lines.
Antero-posterior diameter of last upper molar ..........-..-.--- 18 18
Transverse diameter of last upper molar ............-...-...--.| 19 163
Antero-posterior diameter of second upper molar . ..-.......-- a 19 16
Transverse diameter of second upper molar .....--...-..------- hSi18 16
Antero-posterior diameter of last premolar.-......... ...-..--. 105 9
iransverse diameter of fast: premolar ...............-.+-...---.. ioareee 525! 11
Antero-posterior diameter of second premolar ...... -. - gre eye 9 8
‘Transverse diameter of second cea Ro ts ee Be AK otal hey. Ls 7s fi
JOSHI CEL RONAORCONE (OE 10102 es Ea oe ee | gS tin Celie aan
Antero-posterior diameter of base of canine ...........-... eo | Opes lees 725 sp
Mransverse diameter of base of canine............-....------.-- |" es weer ea
Pie Meuen on tans On GAMING. =. Ve skeen oe eee ee ase ee see cles 11 124
Menetivon crown of lateral Incisor..........-. ...-.--..---0-«-6: Nae Fi eae pe
Miameternor base Ob CrowMVOf MCISOr.......-..------ace-cccncec | 7 eae is
Drameter Of tans Of Mcisor...<............---... ee ese oe | CU i ere eee:
| '

A small collection of teeth belonging to the larger Palzeosyops was obtained
by Dr. Carter in a butte ten miles distant from Dry Creck Cafion. Among
the specimens there is a series of upper premolars, from the second to the

7G

50

last, inclusive, represented in Fig. 12, Plate XXIII. The crowns of the
teeth are worn, and also somewhat eroded, but not to such an extent as to
obscure their characters.

The last upper premolar agrees with that previously described and referred
to Paleosyops major, except that it is of more uniform width.

The third premolar is a reduced representative of that behind it, but is also
proportionately of less width transversely.

The second premolar is like the corresponding tooth above described and
referred to Paleosyops major, but is considerably narrower fore and aft.

A much worn upper true molar, partially broken away externally, is rather
smaller than the specimen of a second upper molar above described and
referred to Paleosyops major. It sufficiently accords with it to be the first
of the series of true molars.

Another specimen consists of a mutilated canine, intermediate in size to
the more perfect one above described, and the larger one, contained in the
facial specimen described under the head of Palg@osyops paludosus. ‘he fang
toward the extremity is more curved than in either of the other specimens.

An upper lateral incisor was about the size of the one previously described,
but has a stouter fang. Its crown, broken toward the point, is deeply worn
away internally. :

Another incisor, a lower one, is represented in Fig. 15, Plate XXIII. It
has a short, conical crown, with a strong basal ridge posteriorly.

The measurements of the specimens are as follows:

. Lines.
Antero-posterior diameter of upper true molar, estimated........ -.-.--..----. 16
Transverse diameter of upper true molar.....-..----- wt. 20)3 do 18
Antero-posterior diameter of upper last premolar...........-.--..---.-------- 83
Transverse diameter. of upper last premolar, ...-...- 22255. 32.22 see 124
Antero-posterior diameter of upper third premolar.............--..------..---. 8
Transverse diameter of upper third premolar ..-2.-..0 25-6. 2 o25--5 2 eee 104
Antero-posterior diameter of upper second premolar ...:...-.-.--.---.-..----- 7
Transverse diameter of upper second premolar......--. eames ses, - = - s oe
Length of fang of canine .oo sitet sein ete See ee er 25
Diameter‘of fane of canines, 124.530.cce hac die ei ee > ee ee ee
ihenothyof tans of upper Ineisor.:-2-- =e on = = ee ee eee Set Sk 22
Diameter of fane of upper Ineisors.2 ~~ 2+. = ee ee eee 74
jneneth:ot crown of lower incisor 4. 224-4. ee nes eee ce ee eee ee eee 6
Antero-posterior diameter of lower ImCiSOr: = _ 2s =-32 22322 25-222 22 - eee eee 6
ranswerse.diameter jor. lower iNCisoOn +. 22.6 .ceecr saace = «ec es See eee 5

An important and instructive specimen pertaining to Pal@osyops mqor is
represented in Fig. 16, Plate XXIII, and Fig. 1, Plate XXIV. It consists

Dit

of a cranium, discovered by Dr. Carter in the buttes of Dry Creek Canon.
The specimen was broken into many pieces, but these have been united so
as to give us a good idea of the shape and construction of the cranium. This
is of remarkable form, and exhibits more resemblance to that of a bear than
to that of its nearer relative the tapir.

The forehead, as seen in the upper view of the cranium, Fig 16, Plate
XXIII, forms a long triangle, with the apex prolonged backward and expanded
at the summit of the occiput. Its fore part more abruptly widens as it extends
outwardly upon the conspicuous postorbital processes. Its surface from the
apex forward is strongly convex, but approaching the muzzle between the
position of the postorbital processes it becomes in the same direction con-
cave. Transversely it is nearly straight between the boundaries of the tem-
poral fossee, but is convex between the postorbital processes. The latter
are strong and unusually prominent, trihedral, hook-like projections. Their
upper acute border forms the anterior extension of the temporal boundary
from the forehead. Their supra-orbital margin curves from the face back-
ward and outward to the point. Their anterior or facial surface is depressed
or concave.

The postorbital process preserved in the specimen is broken at the end,

but is there so narrow as to make it appear that it did not meet an ascending
process from the malar bone as to form a postorbital arch. The strongly
arched supra-orbital border is directed outward with a moderate backward
inclination, indicating a more forward direction for the orbit than in the tapir
and rhinoceros.
The short postorbital eminence of the malar bone in the facial specimen
referred: to Paleosyops paludosus, and represented in Fig. 51, Plate XVIII,
would also indicate that the orbits were open behind in Paleysyops, notwith-
standing the great length of the postorbital process of the frontal in the
specimen under consideration.

The base of the muzzle, or the face, between the position of the sete Is
broad and convex.

The specimen exhibits no evident traces of the sutural conjunctions of the
parietals, frontal, the maxillaries, and the nasals.

The cranial crest separating the temporal fosse is exceedingly short com-
‘pared with that of the tapir. It is formed by the approach of the temporal

boundaries, which appear in this position as two obtuse ridges squeezed

52

together, and leaving between them a narrow groove extending from the fore-
head to a transverse concavity at the summit of the occiput.

The temporal fossee are of huge proportions, and appear even to exceed those
of the greatest living carnivores, as the lion and the Bengal tiger. The zygo-
mata are as prominent as in these, but are proportionately of greater strength,
being both deeper and thicker. Excepting in their greater extension out-
wardly from the posterior root, as in the latter animals, in their sigmoid direc-
tion downward and forward they are more like those in the tapir. Their
outer surface is convex, and is directed obliquely upward.

The temporal surface at the side of the cranium, and extending on the
zygomatic root, forms a’deep excavation or concavity slightly overhung by the
upper part of the temporal ridge. It exhibits a comparatively feeble swelling
about the position of the squamous suture, but much less conspicuous than that
in the tapir. The great hollow of the temporal surface is in striking contrast
with the swelling of the corresponding surface in the great living carnivores,
and while it is expressive of an equal if not greater extent of powerful muscles,
it is further expressive of a proportionate decrease in the capacity of the cra-
nium and therefore of a much smaller brain. .

The cranium is constricted at the sides at the lower part of the temporal
fossee, just in advance of their middle, and the fore part, independent of the
extension of the zygomatic roots, appears nearly as wide as the back part.

The squamosals are large, and reach half way up the temporal surface. A
conspicuous group of neuro-vascular foramina occupy their upper back part,
including the contiguous part of the parietals. The occiput is wider than
high, is strongly concave above, but at.the lower part slopes backward to the -
margin of the occipital foramen. Its sides below are bent forward, as in the
tapir, and the lateral borders above, as in the latter animal, are produced in
wing-like expansions. The basal angles of the occipital triangle are formed
by comparatively short, wide processes, composed of the conjoined paramas-
toid and post-tympanic processes. ‘These extend from within the position of
the oecipital condyles and reach outwardly a considerable width beyond them,
but do not project much below the root of attachment of the condyles. The
occipital condyles are of greater proportionate width but less depth than in
the tapir or the bear; and they project from the occipital surface backward
more than in either of those animals. The occipital foramen is transversely

oval.

53

The general plane of the occiput is intermediate in its degree of inclination
to that of the ‘tapir and our large carnivores, and is indeed nearly vertical.
The occipital condyles project posterior to the general surface, and thus form
the most prominent portion of the occiput, whereas in the tapir, bear, and cats
the summit of the occiput is. most prominent backward.

The articular surfaces of the condyles extend forward on the basi-occipital,
“and approach quite near each other, as in the bear.

A large venous foramen occupies the course of the occipito-temporal suture,
about. the center of the lateral plane of the occiput.

The auditory archway is high and narrow compared with that of the tapir.
It is widest above and has its sides converging inwardly.

The post-glenoid tubercle, compared with that in the tapir and bear, is very
thick and strong. It is broad and mammillary, and is directed obliquely out-
ward and projects downward below the post-tympanic process. The base of
the cranium is very broad compared with that of the tapir, and in this respect
is more like that of the great carnivores. |

The basi-occipital is broad and thick. It narrows. forward from the posi-
tion of the paramastoid processes. Its sides are concave from before back-
ward, slope strongly from the upper edge toward each other, and are sepa-
rated by a median carina which expands behind and-ends in front in a prom-
inence. The basi-sphenoid, completely co-ossified with the basi-occipital,
appears as a narrowed extension of this, and is transversely convex.

Large vacant spaces, occupied with the matrix of the ‘fossil, are Sane
below the position of the petrosals. The tympanics are lost.

The glenoid articular surface is broad and nearly horizontal above, and
extends obliquely downward, outward, and backward on the robust post-
elenoid tubercle.

The anterior condyloid foramen is situated about three-fourths of an inch
in advance of the occipital condyle.

The root of the pterygoid process is pierced with an ali-sphenoid canal, and
the oval foramen occupies a position just above it.

Measurements of the cranium are as follows:

Length of cranium from the concavity at the summit of the occiput to a
line between the post-orbital processes, following the curvature of the

HOTICINCRNOUS, eS ego Pele Be oy 2 Oa 9 inches.
Breadth across the face, following the convexity between the ends of the
[UAGISE=OD OOM TL T OROYCESISE NS «= Ss ct Ne gg S4 inches.

Distance between the orbits across the face above ............--...--.-. 6 inches.

D4

Thickness of the short cranial crest separating the temporal fossie poste-

Tiorly A: ) = +o deme ela pits Says eee eee ee ie ee ne SER ee ene ei % inch
Breadth of temporal foss:e from the occipital border to the end of the post-

Orbital’ PVOGESH Ss ors wm. Sage Stet sate cede Re enon lec earners Te oars 9 inches.
Vertical extent in advance of zygomatic root... 7-1 25. Sie eeee eb ses 5 inches.
Breadth of cranium outside of zycomata. 5.2 sec coc a= omer ere ee 11 inches.
Height Gf O¢Cipit.: 20:2. ey.) s 2s suiee eats eerie See eee eee 53 inches.
Breadth of occiput at post-tympanie processes .----.-.:-..20-22--. o-- ee 635 inches.
Breadth of cranium at ends of post-glenoid processes.... .....-. --.---- 8 inches.
Dransverse: diameter of occipital foramen, = oe hee. sastece. 5a eeene oh s0) Qo Ae
Vertical diameter of occipital foramen, estimated..........--.-+-.-...-. 16 lines.
Breadth at occipital condyles together 21-2...) 22k ae. See ee 47 lines.
Depth of occipitalycondy less. y-) sap eee ere sie egg a Been By ceo ee 18 lines.
Breadth of occipital eomdyles <r. cect any soins eee ee rey el 19 lines.
Width of basi-occipital at anterior condyloid foramina ...-. ......-.-.--- 15 lines.
Width of basi-occipital at conjunction with basi-sphenoid...-.....-..--.. 15 lines.
Distance between glenoid articular surfaces.............-..-...----.-.- 51 lines.

An upper-jaw fragment, from the same individual as the cranium just
described, contains the last two molars, of which the penultimate one is rep-
resented in Fig. 3, Plate XXIV. This tooth closely resembles the corre-
sponding one of the same species represented in Fig. 10, Plate XXIII, and
also that of Paleosyops paludosus as represented in Figs. 3 to 5, Plate IV, and
Fig. 9, Plate V. The last molar, as far as it is preserved, likewise resembles
the corresponding tooth represented in the same plates. The inner part of
the crown presents a single conical lobe.

The infra-orbital border forms a thick, obtusely rounded ledge projecting
obliquely forward on the face. In Palg@osyops paludosus the corresponding
ridge presents an acute anterior edge defining it from the facial surface beneath.
The outer part of the thick infra-orbital ridge rises in a short, blunt, conical emi-
nence or postorbital- process. The orbital floor is concavely depressed within’
the prominent margin, and forms a long, triangular platform terminating
behind in the thick posterior boundary of the maxilla.

The measurements of the specimen are as follows:

Lines
Space occupied by the last’ two molars). =... 65.5) 2) ee ee 32
preadth-of second molar. sf th SRS eye Oe ee ye pee) ee ne me a E20
Miudth of second! molar .4. 452 4ecp eee ee one eee eee eee ets Sc: - 20
Height of anterior orbital margin from the molars ...--.....-...-...---..---.--< 26

Fragments of both sides of the lower jaw with all the teeth broken away,
except portions of the last molars, also accompany the preceding specimens.
The best preserved fragment partially restored from the corresponding por-
tion of the opposite side is represented in Fig. 4, Plate XXIV. It agrees in

55

form and proportions with the same portion of the jaw in Pal@osyops palu-
dosus, excepting that the masseteric fossa is much deeper. ‘The- preser-
vation of the angle of the jaw, not retained in any of the previous specimens of
Paleosyops, permits the determination of its character. It presents a nearly
semi-circular border projecting moderately below the base of the bone, and in
a less degree posteriorly. Toward the base it is somewhat bent inward.

The last molar, in a restored condition, of the natural size, is represented
in Fig. 14, Plate XXIII, but, unfortunately, the artist has made its thickness
in front proportionately too great.

The measurements of the specimen are as follows :

Paleosyops: Palzosyops
major. paludosus.
. Lines. Lines.
_ Distance from last- molar to back border of jaw....-....-..--.-- G1 49
Depth from condyle to bottom of angle..........-....-...-..-. Meee hat
Depth of jaw below fore part of last molar.................-...- : Sey 3
Thickness of jaw below fore part of last molar........-..-..--- 16 | 14
Lo eG eC IS) 0) 00) 0 22 19
Width at fore part of last molar tooth ......-..-... FE Eee 13: | 104
Width at middle part of last molar tooth.............. ..... 115 | 94

Fragments of another jaw similar to the above, and presenting the same
comparatively deep masseteric fossa, were found by Dr. Corson at Grizzly
Buttes.

Fig. 2, Plate XXIV, represents a mutilated facial portion of a skull appar-
ently referable to Palaosyops maor. ‘The specimen was found on one of the
buttes of the Bridger formation by a Shoshone Indian, and brought to Dr.
Carter, by whom it was presented to the writer. Though much distorted in
form, it gives us a fair idea of the shape and construction of a portion of the
skull of Palzeosyops that we had not previously had the opportunity of ex-
amining. ° It is crushed in such a manner that the upper part of the face is
pressed downward and toward the right side, and the orbit has ‘its roof
brought near to the floor, so that it looks as if it were closed behind by the
presence of a postorbital bridge.

The specimen shows that the form and construction of the face of Palzo-
syops are very similar to what they are in Paleotherium. The upper part of
the face appears to have been directed in a moderately sigmoid course, nearly.
horizontally from the bottom of the convex forehead to the end of the muz-

zle. The nasals are large, thick, and strong. Proportionately they exceed in
length those of the Palwothere, the rhinoceros, and the tapir. If I mis-
take not a fracture for a suture, their posterior extremity reaches as far as the
position of the fore part of the orbits, and their free extremity projects quite
as much as the jaws. They are strongly arched transversely and are more
abruptly rounded and thick at the lateral borders. They gradually narrow
forward and terminate in a blunt extremity, which is nearly straight but
rounded at the outer angles. Posteriorly, they include a deep and wide an-
gular notch, which receives a corresponding angular prolongation of the
frontals.

The lateral nasal notch resembles that of the rhinoceros, but is propor-
tionately of greater depth, and in this respect also resembles that of the
Paleothere. Its exact extent cannot be determined on account of the mu-
tilated condition of the specimen.

The upper jaw in its form and proportions is nearly like that of the. Palibo:
there. It is of greater proportionate depth below the orbit, and exhibits a
greater swell at the border of the nasal notch, due to the greater size of the
canine teeth. The infra-orbital foramen is large, and is situated over the
position of the last premolar. The hard palate is flat along the middle an-
teriorly. Its posterior part is destroyed in the specimen, so as to prevent
the determination of its extent.

The incisive foramina appear to be comparatively small and widely separated.

They appear also to be circular, and continuous with grooves descending for-_

ward to the incisive alveoh.

The teeth form a series as unbroken nearly as in Anoplotherium. They
are all mutilated in the specimen, but the crown of the last premolar, and the
molars are sufficiently well preserved to exhibit the characteristics of Palzo-
syops as already described.

Measurements of the specimen, for the most part approximative on account
of its distorted condition, are as follows:

Length of jaw from back of last molar to front of incisive alveoli ---.. 9 inches.
Length of face from the anterior orbital margin to the end of the nose... 7 inches.
ength of the nasals in the mediansline--—c--- ee eee ee eee 5 inches.
Breadth of the nasals together atiwheir middlets-— eee =e er 52 inches.
Length of space occupied by the molar series.....-..-.-.- -.---------- 64 inches.
Length of space occupied by the true molars.....-..---.-....---------- 3% mehes,
Breadthvoilastipremolar s . 0.6 a2 ce seed ee ee eee ae A aoe eee SO eee

Widtheoflastpremolar’. ...0.. 28. Seta Ae ee Le Be

emardlth, af figs ing aie seo ee le ee ne eee 142 lines.

Wii GietinsGunOlawec =) scene sje So2 2 225% <2 Sear NOTE. eee aN be AS 144 lines.
Breadth of second molar.....-. 3 Is aS SE ee Aer aa tae i Oe | ea MR ae LR 16 lines.
NV adlhmoimsse Come mmol ar Na = a7-120s 2 oe Se wi a re si Pg Se alee jae -. 16 lines.
Nera RO RE ASU ATOM eri rr. ii Sy yas) fs, cx ciel 2 ia eee a ois Sey Su oe Se 194 lines.
DgrcnimotnlastemOlat.o-. .4 once Since yee wos CAG wer ane AE ec, 2 ane ees 18 lines.
Madihnvot palate between canines: so... is/.. 6)... Se keels ed ca! 28 lines.
rcp Oi canine alveOliete ee. te Naty Wee ese ee 9 lines.

PALZOSYOPS JUNIUS:

Dr. Carter recently sent the writer several small fragments of the right
side of a lower jaw, together with a sketch of a larger fragment of the left
side, containing the last premolar and the succeeding molars. The speci-
mens were obtained from the Bridger beds, and appear to indicate a small
species of Palzosyops, though it-is not improbable that they pertain to a
small variety of P. paludosus.

The parts agree closely with the corresponding parts of the lower jaw and
teeth of the latter, except in size. They have been viewed as representatives
of a species with the name of Paleosyops junius.

The measurements of the teeth in comparison with those of P. Peredocds

are as follows: :

Paleosyops) Palieosyops

junius. paludosus.

Lines. * Lines.
Space occupied by the last premolar and molars....-.....--.-.... 48 55
Suaceroceupied by the molars.-..-------.--.-.s2--o-eeec ee eee 393 46
Menu NmOnelast, PROMIOIAT . a2. 2c cis sew cclc we ccc te ce tees dues 8 9
‘Thickness of last premolar............----- OSS cerns ee Ieee dS 64
Joos CUNi Gip athestah (Yo) ES) eee ae salege ae 10 124
ipreadcm of ‘second molar... ..-...-...---.--+-.-- Reeies Giz ES RS 12 15
Ree i Ol HIT IMOLAT 2. = 5 ham ceca. he ae eee ee eee alee SaaS ae 17 19
aimckness of third-molar at middle...-...-.....-.2.-0.s----05- 7 94
LIMNOHYUS.

This genus was originally named by Professor Marsh, in a communication
published in the American Journal of Science for August, 1872, and was
applied to Paleeosyops under the misapprehension that this genus had not
been distinguished by the possession of one or two cones to the inner part of
the crown of the last upper molar tooth. As it was as clearly demonstrated
as the nature of the specimens would admit, that the last upper molars of

8 G

58

Paleeosyops possessed but a single cone to the inner part of the crown, the
name subsequently proposed by Professor Marsh on account of this character-
istic was untenable. Under these circumstances, though I previously viewed
the difference as simply specific, I would adopt the generic name of Limnohyus
for those forms of Paleeosyops, as recognized by the general constitution of
thé teeth, in which the last upper molars have two cones to the inner part of
the crown. :

Fig. 13, Plate XXII, represents an upper molar tooth, apparently the first
of the series of true molars, resembling in form the corresponding teeth of
Paleosyops paludosus. Lhe enamel of the tooth is, however, comparatively
smooth, a condition which is clearly independent of its age, as the tooth is
but moderately worn. As a considerable degree of variation is observed in
the extent of wrinkling of the enamel of the teeth of Paleosyops paludosus,
independent of wearing, it is not improbable the specimen may pertain to
an individual variety of the same, though it probably may indicate another
species.

The specimen was found by Dr. Corson in association with the large tusks
originally referred to Uintamastix atrox, described in a later chapter, and
represented in Figs. 1 to 3, Plate XXV. -

Since writing the description of the smooth, enameled molar tooth, Pro:
fessor Marsh, who has inspected the specimen, informs me that it pertains to
the same animal he has described under the name of Paleosyops laticeps,
(Am. Jour. Sc., Aug. 1872.) As this is stated to have four lobes to the
crown of the last upper molar, for reasons already given, it would helong to
the genus Limnohyus.

Fig. 8, Plate XXIV, represents the crown of an upper molar tooth, which
was found, together with some small fragments of other molars, both upper
and lower, by Dr. Corson on the buttes of Dry Creek Canton. The specimen
I supposed to belong to a small species of Palzeosyops, and so referred it,
under the name of P. humilis, in a letter to the Academy, published in
its Proceedings for July 30, 1872. Under the impression that it was
perhaps the last tooth of the series, in view of the distinction suggested by
Professor Marsh between Paleosyops and Limnohyus, I subsequently
ascribed it to the latter. Professor Marsh informs me-that he has a number
of specimens which lead him to regard the tooth as pertaining to the tempo-
rary series of Paleeosyops.

‘59

HYRACHYUS.

An extinct genus of odd-toed pachyderms, under the above name, was
originally inferred from specimens of fossils obtained during Professor Hay-
den’s exploration in Wyoming, in 1870. One of the specimens, represented
in Fig. 11, Plate II, consists of the greater portion of a ramus of the lower
jaw, without teeth, found on Smith’s Fork of Green River. The other speci-
men, represented in Fig 12, consists of a lower-jaw fragment, with several
teeth, of a young animal, from Black’s Fork of Green River.

Hyrachyus is closely related with the extinct tapiroid genus Lophiodon, the
remains of which belong to the early Tertiary formation of Europe. In a less
degree, also, it is related with the rhinoceros-like Hyracodon of the Mauvaises
Terres of White River, Dakota. Among living animals, it is most nearly
allied to the tapir, and more remotely with the rhinoceros.

The dental series of the true Lophiodon, if the Z. isselense of Issel,
- France, be viewed as the type of the genus, or of Tapirotherium, as it had
been previously named by De Blainville, consists of three incisors, a canine,
three premolars, and three molars. The living tapir at maturity has one pre-
molar more to the. upper series. 2

In one species of Hyrachyus at maturity there are: four premolars to the
series above and below, as in Hyracodon. Apparently, in a second species
there are four premolars in the upper series, and three in the lower, as in the
tapir.

The last lower molar of Lophiodon has a trilobate crown, In Hyrachyus,
as in the tapir, it has a bilobed crown.

The crowns of the lower molars are intermediate in character with those
of Lophiodon and .Hyracodon.

The upper molars of Hyrachyus closely resemble those of Lophiodon. In
both genera the upper back two premolars have a single lobe to the inner
part of the crown representing the inner pair of lobes of the crowns of the
succeeding molars in a connate condition. In Lophiodon a ridge proceeds
from the inner lobe of the crown of the premolars mentioned to the antero-
external lobe. In Hyrachyus, in the corresponding teeth, a pair of ridges
proceed from the inner lobe of the crown to both the outer lobes.

The lower jaw of Hyrachyus has nearly the form and construction of that
of the tapir.

60

HyRACHYUS AGRARIUS.

This species, originally indicated and named from the specimen repre-
sented in Fig. 11, Plate IJ, consisting of a ramus of the lower jaw without
teeth, we have now the opportunity of illustrating by many well-preserved
and more characteristic specimens. Most of these were collected by Dr. J.
Van A. Carter, during the last summer, on Henry’s Fork of Green River,
near Lodge-Pole Trail, at Bridger Butte, and other localities in the vicinity of
Fort Bridger, Wyoming. A few others were obtained by Dr. Joseph K.
Corson, from Grizzly Buttes, Wyoming.

The specimen represented in Fig. 12, Plate II, being one of those upon
which the genus Hyrachyus was originally proposed, was referred to another
species from the former one, with the name of Hyrachyus agrestis. This Il now
regard as of the same species. The specimen, a lower-jaw fragment, belonged
to a young animal, which still retained its temporary teeth. Of these, the
fossil contains the first premolar, the fangs of the succeeding two, and the
molar tooth. Behind this the first molar of the permanent series is inclosed
within the jaw.

Professor Marsh has described remains apparently of the same animal
under the name of Lophiodon Bairdianus. The specimens, which he observes
are among the most common of the mammalian fossils of the Wyoming Ter-
tiary, were found at various localities near Fort Bridger, and also on the
White River, in Eastern Utah.

The dental series of Hyrachyus agrarius, in the mature condition, consists
of three j incisors, a canine, four premolars, and three molars, in both jaws.

A well-preserved series of upper molar teeth, considerably worn, is repre-
sented in Figs. 9 and 10, Plate IV, from a specimen discovered by Dr. Car-
ter near Lodge-Pole Trail, about eleven miles from Fort Bridger. Fig. 11,
of the same plate, represents an upper second molar, which was obtamed by
Dr. Carter on Henry’s Fork of Green River.

Of the upper molars, or true molars, the middle one is the lavoess and the
others are nearly equal in size. Four principal lobes enter into the constitu-
tion of their crown, which is inclosed by a basal ridge, except externally, and
at the most prominent portion of the inner lobes internally. Of the outer
lobes, which are conjoined, the posterior is the wider and is pyramidal ;
anterior is the more prominent externally and is conical. This is also strength-
ened in front by a large conical buttress continuous with the comparatively

61

wide anterior basal ridge of the crown. In the last molar the posterior of
the outer lobes is proportionately less well developed than in the molars in
advance. The inner lobes of the crown are conical internally, and are extended
obliquely outward so as to form ridges continuous with the fore part of the
outer lobes. The oblique valley separating the inner lobes is closed exter-
nally by the conjunction of the outer lobes. A wide, angular recess occupies
the interval of the posterior lobes of the crown and the posterior basal ridge.

In the unworn or moderately worn condition of the molars, as seen in Fig. 11,
Plate IV, a narrow but conspicuous ridge or fold is observed projecting from
the antero-external lobe into the median valley “of the crown. In the
worn condition of the molars, as seen in Fig. 10, e to g, they exhibit a
tract of exposed dentine extending along the summits of the outer lobes
including the abutment in front, and prolonged inwardly in two pouch-like
extensions upon the summits of the inner lobes.

The upper premolars not only exhibit from behind forward a successive
diminution in size, but also a reduction to greater simplicity. The latter con-
dition is induced through connation and disappearance of constituent elements
as they are observed to exist in the back teeth. Thus if we compare the
back two premolars, Fig. 10, ¢, d, with the molars behind, it will appear that
the most striking difference is due to the connation internally of the inner
lobes. From this arrangement the premolars appear to have a single lobe to
the inner part of the crown, from which a pair of ridges proceed to join the
outer lobes. A central pit represents the median valley opening internally in
the crown of the molars. The basal ridge extends around the inner part of
the crown.

The abutment so conspicuous at the antero-external angle of the crown of
the molars is successively reduced forward in the premolars and disappears in
the anterior two.

In the crown of the second premolar, Fig. 10, 6, the outer lobes are more
connate than in those behind, and the inner lobe appears more isolated from
the absence of the intervening ridges.

The crown of the first premolar, Fig. 10, a, about half the size of that of
the tooth behind, is conoidal with an oval base. For the most part it is
homologous with the outer lobes of the other premolars in a completely con-
nate condition. A small offset internally is a rudiment of the inner lobe of

the succeeding premolar.

62

A basal ridge exists at the outer back part of the crown of the second pre-
molar, and, less produced, exists in the same position in the third. No ridge
occupies the inner prominence of the inner lobe of the second premolar.

A specimen of an upper left last premolar, found at Grizzly Buttes by Dr.
Corson, is represented in Fig. 12, Plate IV. Itis larger than in the entire series
of Fig. 10 and is less worn. It exhibits a basal ridge externally interrupted
at the middle; and internally the ridge is also interrupted or nearly obsolete
at the middle. The posterior ridge or fold between the inner and postero-
external lobes, though smaller, is more defined from the lobes than the ante-
rior ridge. The latter appears rather as a prolongation of the inner’lobe to
the fore part of the base of the antero-external lobe. The posterior ridge has
the appearance of an introduced piece defined from the lobes by constrictions
or grooves. The arrangement is badly represented by the artist; nor is it
obvious if it existed in the corresponding more worn tooth of the series of
Fig. 10.

Ina much mutilated specimen, obtained, by Dr. Corson at Grizzly Buttes,
containing the remains of the last two premolars and succeeding two premo-
lars, the basal ridge is better developed at the inner part of the crown than
in any of the preceding. The last premolar exhibits the same condition of
the posterior ridge intervening to the internal and postero-external lobes of
the crown as that described in the isolated tooth. The same tooth, barely
wora, exhibits the summit of the inner lobe of the crown slightly divided into
two points, so that it presents a less degree of connation than in the preceding
specimens.

The upper molars and premolars, except the first one, are inserted by three
fangs, of which the inner one is a connate pair; the connation being most
complete in the premolars. The first premolar has two fangs. The space
occupied by the upper molar series is about 3? inches.

Fig. 13, Plate IV, represents a specimen, found by Dr. Carter, in company
with the upper molar teeth of Figs. 9 and 10, and evidently pertaining to the
same individual. The specimen consists of the anterior extremity of the
lower jaw, retaining the incisive alveoli, the canines, and on one side the four
premolars. A view of the triturating surfaces of the latter is given in Fig.
14. Figs. 15 and 16 represent a second molar, and Fig. 18 an incisor from
the same individual.

Iig. 25, Plate XX, was drawn from a specimen consisting of the greater

63

part of a lower jaw, including both rami, obtained by Dr. Carter, at Bridger
Butte, seven miles west of Fort Bridger. The left ramus contains the pos-
terior three premolars and the succeeding two molars, of which a view of the
triturating surfaces is given in Fig. 26.

The lower molars, including the last one, in Hyrachyus agrarius have all
bi-lobed crowns. These are oblong square, and bounded by a basal ridge in
front, behind, and in a more or less interrupted condition externally. The
constituent lobes have somewhat curved rectangular summits as in Hyracodon
and rhinoceros. The summit of the anterior lobe curves forward and inward,
and becomes continuous with the basal ridge of the fore part of the crown.
As the acute summits are worn, tracts of dentine become exposed
crossing the teeth. In the progress of attrition the expanding dentinal tracts
extend in an irregular L-like manner, and finally the contiguous tracts of each
‘tooth become continuous, as in rhinoceros at the same stage of wear.

The crowns of the premolars present the same essential constitution as
those of the molars, with the constituent lobes, successively, from behind
forward, becoming more reduced or rudimental. The posterior lobe becomes
proportionately more reduced than the anterior, and in the first premolar has
disappeared.

The crown of the last premolar resembles those of the molars, with the
posterior lobe proportionately more reduced than the anterior one.

The crown of the third premolar, in the specimen represented in Fig. 25,
Plate XX, has the same form as in the last premolar, and is simply reduced
in size. In the specimen represented in Fig. 13, Plate LV, the tooth looks
different, from the oblique ridge or summit of the anterior lobe of the crown
as existing in the former, being contracted in this into a conical and some-
what more elevated point. This gives such a remarkable difference to these
teeth in the two specimens, that, had they been found isolated, without a
knowledge of their collocation, they would have been attributed to different
genera of animals.

_ The anterior two premolars have an oval crown elevated into a median
conical point and presenting offsets behind and in front, in which may be
detected the rudiments of the posterior lobe and anterior extension of the
anterior lobe of the better developed crowns of the teeth behind. ss

All the lower premolars, as well as the molars, are inserted by a pair of
fangs. The space occupied by the lower molar series in several specimens

ranges from 3 inches and 5 lines to 3? inches.

64

The inferior canine teeth are quite like those of the tapir in appearance.
They curve upward and forward, with a slight inclination outward. The
crown is laterally compressed conical, subacute in front and behind, but worn
in both these positions in the specimen under examination.

The upper canines are unknown, unless the specimen represented in Fig.
17, Plate IV, is one. This was found at Grizzly Buttes by Dr. Corson, in
association with some upper premolars of Hyrachyus; all of which look as if
they had belonged to the same individual. The crown of this specimen of
an upper canine is short, and worn off to a considerable extent at its fore
part. It is compressed conical, and has the inner and outer surfaces defined
by an acute ridge posteriorly. The fang is double the length of the crown,
and is laterally compressed. |

The incisor tooth, represented in Fig. 18, appears to be the second of
the series of the lower jaw. It resembles the corresponding tooth of the
tapir. Its chisel-like crown is worn off at the cutting edge.

No characteristic portions of the upper jaw of Hyrachyus have come under
our notice. In one specimen the infra-orbital foramen is observed to occupy
a position above the third premolar. :

The lower jaw resembles, in its form and proportions, that of the Hyraco-
don and the tapir. The anterior extremity, in the construction of the chin,
the contraction between the position of the canimes and molar series, and ~
other features, repeats the condition observed in the tapir. A similar wide
hiatus separates the canines from the molar teeth. The free border of the
hiatus, upward of an inch in length, is concave fore and aft, and acute.

The body of the lower jaw is less robust or thick, in relation with its
depth, than in the tapir.- It is also less convex externally, and at the
base fore and aft. The outer surface, in comparison, appears quite
vertical.

The ascending portion of the ramus rises vertically at its fore border, and
is deeply impressed on the outer surface just back of the latter.

The condyle projects less externally and more posteriorly than in the tapir.
Its articular surface is more flat, and in a less degree inclined inwardly.

In the specimen represented in Fig. 13, Plate IV, five small mental
fofamina are observed, in a row extending from the position of the third pre-
molar to that of the canine tooth. In the specimen represented in Fig. 25, Plate
XX, a large mental foramen is situated below the interval of the third and

65

fourth premolars; and in advance of this several small ones exist. In the
specimen represented in Fig. 11, Plate II, the mental foramen is situated
below the first premolar.

Measurements from several specimens of lower jaws of Hyvachyus agrarius
are as follows:

Lines. Lines. Lines.
Length of space occupied by the molar teeth ........--..-|..--.--- 42 44.
Distance from incisive alveoli to first premolar.........-- 25 Cs ial eat ae ea
Length of hiatus between canine and first premolar ...-... 13 1 Sy Cee eee
Wenner jw below last molar ..--: 22.22... le Seip ies 18 20
Depth of jaw below last premolar..........-.---....---.|.-.-.--. 15 16
Breadth of jaw at canine alveoli ...-...... Bey rest pees 14 Oh 0 Bam ee ee
ivedan of jaw below hiatus........-.. ----- .-+...+-..- 12 dCi ape Ne
Length of symphysis..... .---.--- qa eee peg ae. 3 28 Pei \\SrRe et eis

Measurements of upper molar teeth are as follows:

Inches. Lines.

Menesthot the entire upper molar SerieS..........-. 2.2.62... -c neces ees 3 9
Pe MmOUSELIES Che TCMOMES ca co- c/n 2. n+. neelas so e- ed ee eicelcep ices tees 1 84
Length of series of molars ..... ince rie Mea aaree cad eter aici, Sra. ott Fn 2 14
Fore and aft. | Transverse.
Tines Lines.
iamever OLMNSh PLCWOlAT......-.-<--- saecssees aces score. 4 5
Miamever of second premolar .......-..-..-.....--.-+.----- 5 6
Diameter of third premolar............---.-...-- eee ees 53 7
Miameter of fourth premolar........----- s.+..-.+-----+- ee 64 84
WiMeten Of Me MOAT 22. las... owe ce ee eee cece ees 84 94
iemmaier Of SECON MOlar.~.--- 2. =... -.-- lect eee eee ee eee 94 10
Mmm nemOn GIT MOlAr. ..... . 622s e enn ese ewe ees peer (Bs 94

Comparative measurements of two upper last premolars are as follows:

Lines.
Fore and aft diameter in both..--. SS ter Oe) RO RO ORIN Ie ite Eye Sie ee |
Transverse diameter in one .......--. Gai Stren lcea (x ni op At Bin SOMO he Seta a 8s
Tha HR (WIEN 5 co ote he Ss i eee ee oie aera seen ae eee eae 9
Measurements*of lower molar, teeth are as follows :
Lines. Lines. Lines.
; .
Length of the entire lower molar series.......---..-..---|.--. ----- 42 44
eneth of series of premolars. ......+....-..-2..-.22-5-: 20 19 20
FEA RMOm Gers TOL MOlNG en eiaies ale ocean owen. wen e [dass eeicies 24. 244

one:

66

Fore and aft. Transverse.
Myke ; |

’ Lines. Lines. Lines. | Lines,
Diameter of first premolar... %. 2-46. .2250- ose see 5 ees ae a ee
Diameter of second premolar .... Ne ere tn, iY 44 23 | 26
Diameter of third premolar’. ............----:.---. 6 54 34 | “Sh
Diameter of fourth premolar... .-.-..-..-.--.----- 64 os 43 4
Diameterof first molar \)- << coe S. bee peeee eee ola ee Wes | ate a 5
Diameter of second molar......--.:--... SN, ya ct Oe, |. 2 one os
Dianieteriof third molar: 2.2). Scere eee Eee - ses Si" ee 5

Hyrachyus agrarius was about the size of the common collared peccary,
Dicotyles torquatus.

HYRACHYUS EXIMIUS.

A supposed larger species of Hyrachyus than H. agrarius is inferred from
several specimens, consisting of small fragments of a lower jaw with a tooth
and portions of others. ‘These were obtained by Dr. Carter on Henry’s Fork
of Green River. ‘

The best and most characteristic specimen is represented in Figs. 19, 20,
Plate IV, consisting of a lower-jaw fragment containing the last premolar and
portion of the first molar much worn. Both the teeth and the jaw agree in
form with the corresponding parts in Hyrachyus agrarius and differ only in
size. The specimen also agrees with the corresponding part of Lophiodon
sufficiently to belong to the same genus, so that until more ample material is
discovered it must remain uncertain whether it really pertains to Hyrachyus.

Comparative measurements are as follows:

-

H. eximius. | H. agrarius.
Lines. Lines.
Depth ofjjaw. at last-premolars.. 52-520 eo ee 18 143
Thickness of jaw atJlashipremolar clieu 715-10) ee a- ss ees 9 7
Diameter fore and att of last premolars: . 2 aes ee) 22s eee ee 7 03
Diameter transversely of last premolar_......---- Se ce ees oF 4.
Diameter Lransversly, OL rst molars.) ee ee 64 5
Diameter transversely of second molar..---..-------- Soe e Pu: 7 ot

*
Figs. 9, 10, Plate XXVI, represent a tooth recently obtained by Dr. Car-
ter on the buttes of Dry Creek. It would appear, from its proportions, to be

the left lower penultimate molar of Hyrachyus eximius. It is a nearly un-

67

worn and perfect specimen, and agrees in its anatomical characters with the
corresponding tooth of A. agrarius. The crown measures an inch antero-
posteriorly and 74 lines transversely.

The specimens above described indicate an animal about the size of the
common American tapir.

HYRACHYUS MODESTUS.

Under the impression that teeth of like form with those of Hyrachyus
agrarius, from the Bridger Tertiary formation, pertain to the same genus, I
now view the tooth represented in Fig. 13, Plate II, which I previously
referred to Lophiodon modestus, as belonging to Hyrachyus. ‘The specimen
was obtained during Professor Hayden’s exploration of 1870, on Smith’s Fork
of Green River, near Fort Bridger.

. The tooth is a first or second upper molar, and differs in size and _propor-
tion from the corresponding teeth of Hyrachyus agrarius sufficiently to indi-
cate a smaller species. The only other difference observable, one, however,
which may prove not to be constant in additional specimens, is in the internal
surface of the antero-internal lobe of the crown, bemg strongly wrinkled in-
stead of being elevated in a single conspicuous fold as in H. agrarius.

The comparative measurements of the specimen are as follows:

|
| .
H. modestus. | H. agrarius.

|
}
hee de:
Lines. | Tines.
|

Diameter fore and aft of second upper molar..........-.----- b 9
Diameter transversely of second upper molar.......--..--- : 63 10

Hyrachyus modestus was about a third less in size than A. agrarius. -

HYRACHYUS NANUS.

Portions of two lower jaws I have referred to a small species of Hyrachyus
with the above name. One of the specimens was obtained at Lodge-Pole
Trail, by Dr. Cafter; the other, represented in Fig. 14, Plate II, and Fig. 42,
Plate VI, was found at Grizzly Buttes, by Dr. Corson.

In both specimens, which belonged to animals at maturity but not advanced
in life, the number of teeth in the molar series is six, or one less than in
Hyrachyus, and the same number as in Lophiodon and the tapir. The last

molar, however, has a bilobed crown as in the latter, but the premolars, in

68

their less degree of development in comparison with the molars, are more
like those of Lophiodon.

The suppression of an anterior premolar may perhaps be regarded as a less
important generic character than the others which have been indicated as
separating Hyrachyus from Lophiodon and Tapirus. Under the circum-
stances, notwithstanding the reduction in the number of premolars, I view
the two jaw-specimens above indicated as pertaining to Hyrachyus.

Professor Marsh has described several specimens, from Grizzly Buttes,
under the name of Lophiodon nanus, which I suspect to belong to the same
animal as the lower-jaw fragments above indicated. He observes that the
most characteristic of the specimens is a right upper jaw containing a series
of four premolars and three molars. If, then, this really belongs to the same
animal, it would give with the lower-jaw specimens, as the formula of the
molar series, seven teeth above and six below, as in the tapir. The upper
premolars, however, present a greater amount of difference from the molars
than in the latter, the difference being mainly due to a less degree of develop-
ment of the premolars and in the connation of the inner lobes of their
crowns. ,

The molar teeth and the portion of the jaw containing them are almost repe-
titions of form of the corresponding parts in Hyrachyus agrarius. The men-
tal foramen is situated below the first premolar. Hyrachyus nanus was
about half the size of A. agrarius.

Measurements from two lower-jaw specimens are as follows:

Space occupied by the complete series of molar teeth.....- as Soe oe 2 inches.
Space occupied by the premolarsec--= 0-2 ee see 2 2 oe eee eee 932 lines.
Space,occupied by.themolarswewsre ashe. oe oe ee ee 14 lines.

- Depth of jaw-belowdastjpremolan.- ==. -4ce-ree eo nee ae eee 10 lines.

Fore and aft. | Transverse.

Lines. Lines.
Diametertor frst premolape cc 27 ts ty eee ee 24 if ee
Diameter of Second: premiolaty a. aa re e e He of 2
Diameter of last premolar =. -2 1406 2.44 "33 23
Diameter/of sfirstemolar-ceeer see he ae a eee 4 3
Diameter of second molar... 442-454 5) -eee pene 9 eae 4 34
Diameter or lash molar. o..0 ce eee ae seem ee eee a 53 34

Fig. 11, Plate X XVI, represents the greater part of the right ramus of
the lower jaw of Hyrachyus nanus, which I found, together with a fragment

69

of the opposite side and several other bones of the skeleton, near the Lodge-
Pole Trail, crossing Dry Creek Valley. The specimen was found in part ex-
posed and partially imbedded in the indurated clay of a butte, in company
with quite a profusion of well-preserved shells of Helix wyomingensis.

The jaw resembles in its form that of Hyrachyus agrarius, and also that
_of the recent tapir. It contained a series of six molars, of which it retains
the back four. The molars are separated by a wide hiatus from a continuous
arch of alveoli, for the accommodation of the incisors and canines, which corres-
pond in number with those of the tapir.

The depth of the jaw is rather less than in the fragments previously
described, while the dimensions of the molar series is nearly the same. The
measurements of the specimen are as follows:

Lines
Length of space from incisive alveoli to back of last molar..... oh ies Hie St Sk 49
ens of Space oceupied by the molar Series...: .....2...2.2+.5.0-+-. 2-58: 24
Length of space occupied by the true molars...........-...--..- aay we a eo) il 143
Antero-posterior diameter of last molar......-- REE fine REN Staal apeins 9G 44
Sea anO MMS MN LRUSUSht ere nic at tae ond y oe Meee esa he leehlee eed s Postale hates Ole 16
Pemeriror hiatus im advances Of molarsi 2)... .:2 5.26. Sen eee dw eee eee eee 12
Depth of jaw below molars.... ... ET I REGS tee a oid PS. dan amene) sie Siva o> 94

An upper-jaw fragment, recently sent to me by Dr. Carter, I suppose to
pertain to Hyrachyus nanus. It contains the fangs of the anterior three
premolars, and the entire last one, which is represented in Figs. 21, 22, Plate
XXVII, magnified two diameters. This premolar resembles the corresponding
tooth of H. agrarius, but the ridge in the latter, which represents the postero-
internal lobe in the true molars, is reduced to the smallest rudiment.

The space occupied by the four premolars measures 114 lines. The

breadth of the last premolar is 3.2 lines; the width transversely is 4 lines.

LOPHIOTHERIUM.
LopHIOTHERIUM SYLVATICUM.

The genus Lophiotherium was proposed by Gervais, from some fragments
of several lower -jaws with molar teeth, which were found in association with
remains of true Palotheria, in a formation of France which he regards as
belonging to the upper Hocene Tertiary. The genus is viewed as a tapiroid
pachyderm closely allied to Lophiodon, though the molar teeth appear very
unlike those of the latter.

During Professor Hayden’s exploration of 1870, a specimen was found on

70 :

Henry’s Forkof Green River, whichappears to pertain to a species of Lophiothe-
rium. ‘The specimen, represented in Fig. 33, Plate VI, consists of a lower-
jaw fragment containing the last premolar and the first and last true molars
—the crown of the intervening true molar having been lost. The teeth
appear closely to resemble in form and constitution those of Lophiotherium
cervulum, as represented in Plate Il of Gervais’s Zoologie et Paléontologie
Srangaises. The only apparent difference, which, nevertheless, is an important
generic one, if it really exists, is the division of the summit of the antero-
internal lobe of the crown of the teeth into two points in the American fossil.

The anterior teeth, Fig. 34, of the latter have oblong quadrate crowns,
slightly narrower at the fore part and otherwise alike in form. They are
quadrilobate, the lobes being tri-laterally pyramidal and connate at base. .

The last molar, Fig. 35, is prolonged behind in the manner so common in allied
animals of the same order. This prolongation is mainly due to the addition of
a fifth lobe to the crown, which is narrowed posteriorly in the reverse direc-
tion to the teeth in advance.

A strong basal ridge incloses the crowns of the teeth, excepting internally.
In the last molar it is less well developed and does not exist posteriorly. The
constituent lobes of the crowns are nearly of uniform size. The antero-in-
ternal lobe, as before intimated, has its summit divided into two points. -The
division extends so short a distance that it would be early obliterated from
the wearing of the teeth in the trituration of the food. It is hardly percepti-
ble, even in the unworn condition in the last molar, and in the specimen is
most distinct in the first true molar. Asa character, it may he inferred to be
most obvious in the anterior two true molars, and less so in the premolars of
like form and in the last true molar.-

The postero-internal lobe of the crowns hasasimple pointed summit, The
inner lobes have the crescentoid summit declining from a central point in-
wardly, so common in the corresponding teeth of allied animals. The fore
arm of the summit of the antero-external lobe is a thick ridge curving to the
base of the antero-internal lobe in front. The back arm is a short ridge
directed inwardly to the anterior division cf the summit of the antero-internal
lobe. The fore arm of the summit of the postero-external lobe reaches the
middle of the antero-internal lobe. The back arm joins the posterior basal
ridge, producing an elevated point at its middle. From the inner side of the

71 |

same lobe a third but less conspicuous ridge extends direcily to the lobe
within.

In the last molar the fifth lobe has a crescentoid summit declining from a
median point. ‘The outer arm of the summit joins the contiguous arm of the
lobe in advance, and the inner arm joins the base of the postero-internal lobe.

The minutely detailed description of these teeth, and the same may be
said of those of other fossils, is essential to the distinction of generic characters.

From the back molars of Lophiodon, those of Lophiotherium especially
differ in the distinction of four instead of two lobes to the crown: though the
two lobes in the teeth of Lophiodon and Tapirus represent the four of Lo-
phiotherium in a connate condition.

The jaw-fragment of the fossil referred to Lophiotherium sylvaticum pre-
sents nothing peculiar. The outer. vertical surface is slightly convex, and the
base fore and aft is also moderately convex.

The measurements of the fossil are as follows .

Lines
Depth of lower jaw beiow middle of last premolar............--..--..---- S2e OR
Depth of lower jaw below middle of last true molar....... ....-----..--..---.. 65
Amtero-posterior diameter of last premolar.-:..--.:-..-------.+--+---.----.--- 33
AMLerO-pOSterion diameter of first true molar.......-..-..--.-.------. scene eee 33
amtiero-posterior diameter of second true molar.........----..-0..... 6.00.8 eee 33
Ambero-posterior diameter of last true molar......-.--.-. .-----.-.---.--------- dS
Transverse diameter of last premolar..............------ PRs ay polo ea iets, |
Transverse diameter of true molars.....-- -- RC Ens er aT Se Ee eS See na

Should the duplication of the summit of the antero-internal lobe of the
crown of the lower back molars not be a character present in the Lophio-
therium cervulum of France, it would probably be a concomitant of other
characters in the upper teeth, now unknown to us, which would distinguish
the American animal as generically distinct from Lophiotherium.

In the American Journal of Science for 1871, Professor Marsh notices
some remains, from Grizzly Buttes, which he attributes to a species about
two-thirds the size of the former, and names it Lophiotherium Ballard.

TROGOSUS.

'TROGOSUS CASTORIDENS.

One of the most curious of the extinct mammals of the Bridger Tertiary
fauna is an odd-toed pachyderm about the size of the larger living peccary,
which, with the usual complement of molar teeth, was apparently devoid of

canines, and was provided with a large pair of incisors like those of rodents,

72

The singular character of the animal was first recognized in a fossil specimen,
consisting of a mutilated lower jaw, discovered by Dr. Carter in the vicinity
of. Fort Bridger, and sent to the writer in the spring of 1871. The specimen,
represented in Figs. 1 to 3, Plate V, besides the two large incisors, contains the
remains of most of the molar teeth, but none in an entire condition. The
best preserved is the second molar of the left side, and this is so much worn
as to have the distinctive features of its triturating surface, as seen in Fig. 2,
completely obliterated.

The specimen was originally described in the proceedings of the Academy
of Natural Sciences in May, 1871, and from its peculiarities the animal to
which it belonged was named Trogosus castoridens, or the beaver-toothed
gnawing hog. Professor Marsh had previously described an isolated tooth,
of the same animal, from Grizzly Buttes, which he referred to a species of
Palzeosyops with the name of P. minor. From the description, I supposed it
not to differ from P. paludosus. An examination of the specimen has satis-
fied me that it belonged to the same animal as the jaw referred to Trogosus.

The isolated tooth belonged to a younger animal, and is not so worn as to
have the characteristic arrangement of its masticating surface destroyed. On
seeing it I was struck with its resemblance to another isolated molar tooth
which I had formerly described under the name Anchippodus riparius. This
tooth was discovered by Dr. Knieskern in a Tertiary formation, supposed to
be of Eocene age, in Monmouth County, New Jersey. It was given to Mr.
T. Conrad, by whom it was presented to the Academy of Natural Sciences
of Philadelphia. The same formation has yielded the remains of a peccary,
an Elotherium, and a rhinoceros.

A comparison of the tooth of the New Jersey Anchippodus with the cor-
responding one in the jaw-specimen and with the isolated molar, would appear
to indicate that the Wyoming fossils belong to the same genus, and indeed
the teeth are sufficiently alike in form and size to pertain to the same species.
Should further discovery prove this to be the case, it would, perhaps, indi-
cate the contemporaneous character of the Bridger Tertiary formation of
Wyoming and that of Monmouth County, New Jersey. The New Jersey
fossil, in its general appearance of color and condition, so closely resembles
the Wyoming fossils that it would readily pass for one of them.

It is by no means positive that Trogosus and Anchippodus are the same,

13

for we have examples enough of different genera having the lower molars
alike, while the upper ones and the premolars are unlike.

The jaw of Trogosus retains evidences of the existence of six molar teeth,
and there may have been another small premolar, but this cannot be ascer-
tained from the mutilated condition of the specimen. The first of the series
of six molar teeth approached so close upon the large incisor as to leave but
a small interval for the introduction of other teeth.

The best preserved tooth of the molar series, the second molar, presents a
bilobed crown, in which the anterior lobe is the longer or least worn. The
triturating surface, represented in Fig. 2, Plate V, exhibits a wide tract of
exposed dentine with a yoke-like outline of enamel. Its fore and aft meas-
urement is 94 lines. The thickness of the anterior lobe at base is 8 lines.

In the less worn specimen of the corresponding tooth described by Profes-
sor Marsh, he gives the antero-posterior diameter as 10 lines; the transverse
diameter at the summit of the lobes of the crown as 5 and 54% lines wide.

The constitution of the lower molars of Anchippodus is apparently the
same as in Trogosus, as observed in the New Jersey tooth represented in
Figs. 45, 46, Plate XXX, of “‘ The Extinct Mammalian Fauna of Dakota,” &ce.
From this it will be seen the crown is composed very nearly on the same
plan as that of the corresponding teeth in Anchitherium, Palzotherium, &c.
It is composed of a fore and aft pair of lobes with crescentoid summits,
convex externally and with a recess internally. The size of the tooth is the
same as that retained in the jaw-specimen above described. The fangs of
the last molar in the lower jaw indicate a trilobed crown, as in Anchitherium,
Paleotherium, &c. The premolars, so far as can be ascertained by their
remains in the jaw, are inserted by two fangs. Canines most probably do
not exist in Trogosus, their absence being fully compensated by the large
incisors.

The incisor teeth on both sides together are four in number; but while
the lateral ones are developed to the .proportions of those of rodents, the
intermediate pair were quite small. The latter are lost from the specimen,
leaving the alveoli occupied by matrix. The space they occupied was about
the fourth of an inch from side to side.

The large lateral incisors are wonderfully like the incisors of rodents, not
only in form, position, and structure, but they were also alike in their perpet-

10¢

74

ual mode of growth. They do not extend so far back within the jaw as in
most rodents, and in this respect are more liké those in the rabbits, or, as in
their nearer relatives, the peccary and hog. They extend beneath the pre-
molars, but the bottom of the alveolus does not reach the position of the first
molar.

The incisors are-convex in front, and not flat, as usual in rodents. The
anterior convexity is invested with thick enamel longitudinally striated, the.
striz being wrinkled. [Externally the edge of the enamel appears proportion-
ately more prominent than in rodents; that is to say, it projects more above
the level of the contiguous exposed dentine. In transverse section the incisors
are ovoid, with the narrow extremity behind. The fore and aft diameter of
the section is 10 lines; the transverse diameter at the edges of the enamel -
layer is 64 lines. The anterior convexity covered with enamel is 4 lines;
the posterior convexity is $ an inch.

The cutting edges of the incisors are broken, but the extremities of the
teeth are sufficiently well preserved to exhibit the manner of wearing. They
were not only worn in a sloping manner backward, as in rodents, but also
externally, so that it appears the upper incisors were more divergent than the
lower ones, and held a position related .to them more like the condition
observed in the peccary.

The rami of the jaw, as usual in pachyderms, are completely co-ossified.
The symphysis is remarkably strong and deep, and in the median line is
nearly 3 inches in length. The rami just back of the symphysis are nearly
an inch thick. The chin forms a long, broad slope, defined at the sides by
the prominences of the large incisor alveoli, curving from the base of the
jaw parallel with each other upward and forward. The chin resembles that
of the peccary or rhinoceros, but is more convergent, as in the beaver.
Approaching the exit of the large incisors from their alveoli the intermediate
space is deeply grooved, as represented in Fig. 3.

The body of the ramus is short, deep, and thick. Its outer surface is ver-
tically convex. The base is thick and convex fore and aft as well as trans-
versely.

The masseteric fossa is deep, and extends downward to about the middle
line of the body of the ramus. Two mental foramina on one side, and three
on the other, occupy a position in advance of that of the last premolar.

15

Measurements taken from the lower-jaw specimen are as follows:

. Inches. Lines.
Distance from incisive alveoli to back of last molar......... ....-....--- 4 10
Space occupied by the molar teeth, estimated .................----...... 4. 0
Space occupied by the true molars .........--..--..- Oe ie herd eae ete See 2 7
Hore and att diameter of last.molar ...-.........-----+---:++-- ee a Se arts mI iL
MIM INOL Taw. AtiSCCONG MOAT S510 2+ fe eee eae ee eee ee see aes Beate |
Minckness) of jaw below Second! molar). :2.2..52004. -) 2422 2ee lee ees eed. 0 10
Penimated length o£ lateral imeisOrs,o- -. 42 j-ssaccise2a2-ce(s «eee eel ene 3 3
Depth of symphysis following its slope ...........-. ap le s secles 2 ee 2 10

TROGOSUS VETULUS.

An apparent smaller species of Trogosus is mdicated by the fragment of an
incisor tooth, represented in Fig. 43, Plate VI. The specimen was discoy-
ered by Dr. Carter in the vicinity of Fort Bridger, and sent to the writer last
summer. It consists of the exserted portion of the tooth, and agrees in form
and proportions with the corresponding portion of the incisors in the jaw-
specimen above described. The enamel is smoother, but invests the tooth to
the same relative extent. The antero-posterior diameter of the tooth has
been about 8 lines; the transverse diameter 4 lines.

HYOPSODUS.
Hyoprsopus PAULUS.

One of the smallest of pachyderms, referred to a genus and species above
named, is established on many specimens, chiefly consisting of portions of
lower jaws with teeth, (Figs. 1 to 9, Plate VI.) It was originally indicated,
from a lower-jaw fragment with teeth (Figs. 1, 2) of an old animal, discov-
ered by Professor Hayden, in 1870, in the vicinity of Fort Bridger, Wyo-
ming. Since then the writer has received a number of more characteristic -
specimens, obtained by Dr. J. Van A. Carter and Dr. Joseph K. Corson, at
Grizzly Buttes, Henry’s Fork of Green River, Lodge-Pole Trail, and other
localities in the neighborhood of Fort Bridger, Wyoming. .

The animal was rather less in size than the Aphelotherium Duvernoyi of
Gervais, the remains of which were found in the gypsum quarries of Paris,
France. It also appears to have been allied to this, as indicated by the num-
ber, relation, and constitution of the teeth. Both Aphelotherium and Hyop-
sodus possessed unbroken arches of teeth to the jaws, as in the Anoplothe-
rium, whose remains are found in association with those of the first-named

genus.

76

The number of teeth in Hyopsodus appears to be three incisors, a canine,
and seven molars to the series on each side of both jaws.

Neither incisors nor canines are preserved in any of the specimens we
have the opportunity of examining. Two lower-jaw specimens retaining
portions of the incisive, canine, and premolar alveoli, and the true molars,
apparently prove the number of teeth to be as above indicated.

The canine tooth of Hyopsodus is comparatively of small size, though
larger than the incisors or the first premolar. It appears to have about the
same size in relation with the other teeth as in Aphelotherium and Anoplo-
therium.

The premolars successively increase in size from the first to the fourth.
The first possesses a single fang; the others two fangs. The anterior two
premolars are lost from all the specimens under examination.

The inferior true molars (Figs. 1 to 9, Plate VI) of Hyopsodus have
oblong quadrately oval crowns, with the fore and aft diameter exceeding the
transverse, which is about equal to the depth. They are inserted in the
usual manner in pachyderms by a pair of fangs, the posterior of which in
the last tooth is widened backwardly, as is commonly the case in congeneric
animals.

The crowns are composed of four principal lobes, connate at base; but
the crown of the last tooth has an additional or fifth lobe at its back part as
well developed as some of the lobes in advance. A rudiment of this fifth
lobe is recognized in the other true molars as a small tubercle, occupying a
corresponding position.

The four principal lobes of the crown of the true molars are arranged in
pairs not quite transverse, but slightly oblique, so as to appear somewhat
alternating. The fifth lobe of the last molar is opposite the interval of the
pair of lobes in advance.

Of the four lobes, the outer are demi-conoidal, and the posterior one is
slightly the larger. The inner lobes are simply conical, and the anterior is
the larger. The outer lobes in the unworn condition have acute crescentoid
summits, or form V-like ridges, with the arms declining from the pointed
angle. The inner lobes in the same condition have pointed summits. |

The contiguous horns of the crescentoid summits of the outer lobes join
the antero-internal lobe. The anterior horn of the crescentoid summit of the
antero-external lobe curves inwardly to the base of the antero-internal lobe.

al

The posterior horn of the crescentoid summit of the postero-external lobe
ends in the tubercle at the back of the crown, and in the last molar, in the
homologous fifth lobe. The latter is joined by an acute ridge, descending to
the base of the postero-internal.lobe. |

A thin basal ridge exists at the fore and back parts of the crown of the
first and second molars, and the fore part in the last molar. An element
also exists at the interval, externally, of the outer principal lobes, and in some
specimens is more or less produced around the bottom of the antero-external
lobe. ;

As the crowns of the true molars are worn away, circular islets of dentine
appear at the summits of the inter lobes, and crescentic islets at the summits
of the outer lobes. In the progress of attrition the dentinal surfaces expand,
and the horns of the crescentic islets become united with the circular islets.
In an advanced stage of wear the triturating surface of the molars presents two
elliptical surfaces crossing the crown, with a slight obliquity, and united by a
median isthmus, the whole bordered by a band of enamel. Such a condition
is seen in the specimen represented in Figs. 1, 2, Plate VI, which is that
upon which the genus was originally proposed. By comparing this with the
others in different stages of wear, represented in Figs. 3 to 9, of the same
plate, its correspondence with these, which preserve more characteristic
generic marks, can be readily recognized.

The last lower premolar of Hyopsodus (Figs. 5, 8, Plate VI) is smaller
than the true molars, and like them is inserted by a pair of fangs. Its crown
is proportionately of greater depth than in the true molars, and, as in these, is
widest fore and aft. The outer fore part of the crown is composed of a demi-
conoidal lobe, which is the principal one, and it corresponds with the antero-
external lobe of the true molars. It has the same form as the latter lobe, but is
better developed. The anterior horn of its crescentoid summit forms a curved
ridge, defining the fore part of the triturating surface of the crown. The poste-
rior horn of the crescentoid summit terminates in a small conical lobe occupying
the middle of the crown internally. The back of the crown is formed by a
broad heel, skirted by a basal ridge externally, and divided by another ridge,
which descends from the summit of the principal lobe of the crown, and bor-
ders the heel posteriorly and internally. A thin basal ridge occupies the fore
part of the crown. In the wearing of the crown of the last premolar, the
exposed dentine assumes the form of thes Greek letter e, lying on its right

side.

78

The penultimate lower premolar (Fig. 8) is a reduced form of the one
behind, with the internal median conical lobe obsolete.

The lower jaw has its two rami co-ossified at the symphysis. It is thick
and rounded at the base, which is convex fore and aft beneath the molar
series. The chin is rounded transversely. The masseteric fossa is well
marked and defined anteriorly by a prominent ridge descending from the
front border of the coronoid process to the lower third of the side of the jaw.

The ramus of the jaw would appear to have increased in depth and
assumed a more robust condition in the advance of age, for in those specimens
in which the teeth are least abraded, the jaw is shallowest, and in that in which
they are most worn it is deepest. Specimens exhibiting the teeth in an
intermediate state of wear have the jaw of intermediate depth and strength
to the others.

All the specimens represented in Figs. 1, 3, 4, 6, and 7 I attribute to the
same species, notwithstanding the difference in the proportion of length to
depth in the different ones.

‘T'wo or three mental foramina occupy a slightly variable position beneath
the premolars. :

During the summer of 1871, Dr. Carter discovered, at Grizzly Buttes and
Lodge-Pole Trail, several specimens, consisting of fragments of upper jaws
with well-preserved teeth, which are of a size and form that would adapt
them to the lower-jaw specimens of Hyopsodus. ‘The specimens from
Grizzly Buttes were accompanied by one of the lower-jaw specimens upon
which the latter was founded, and this looks sufficiently like several of them
in general appearance to have belonged to the same individual.

One of the specimens represented in Fig. 18, Plate VI, contains a series
of three premolars and the succeeding molars. In advance of the series there
remains a portion of an alveolus which apparently belonged to another pre-
molar. If such is the case, the number of premolars would be the same as
in the lower jaw of Hyopsodus.

The teeth (Figs. 18 to 22) increase in size from the first to the sixth, the
seventh being again reduced to the size of the fifth. The second premolar
is inserted by a pair of fangs of which the posterior is wider than the other.
The succeeding premolars and molars are inserted with three fangs, of which
the inner one of the molars is a connate pair.

The crowns of the molars (Figs? 19 to 21) are quadrate, wider transversely,

79

and about half the depth of the breadth. They are composed each of six
lobes expanding and continuous at base. The outer and inner pair of lobes
are nearly equal; the intermediate pair is smaller.

The outer lobes of the molars are conical, and united where contiguous,
but they do not form an external buttress by their union, the intervening
surface externally beg concave. In the last molar the posterior of the outer
lobes is proportionately less well developed than in the others.

The inner lobes of the crown are likewise conical, and united where con-
tiguous. The posterior of these lobes is the smaller, and in the last molar is
entirely suppressed, or appears only as a slight elevation of the basal ridge
occupying the back of the crown. The summit of the antero-internal lobe
is prolonged obliquely to join the antero-median lobe. The summit of the
postero-internal lobe is prolonged outwardly back of the postero-external
_ lobe, so as to appear as a basal ridge to this part of the crown.

‘The median lobes hold a slightly more advanced position than the includ-
ing lobes. The back one is isolated or free to its base; the front one, by
prolongation, is associated with the antero-internal lobe and the fore part of
the base of the antero-external lobe.

A strong basal ridge occupies the fore part of the crown, and also, less well
developed, festoons the outer part.

In the wearing of the upper molars (Figs. 19 to 21) islets of dentine first
appeared at the summits of the six lobes of the crown. Those of the two
outer lobes soon became continuous; followed by those of the antero-median
and anteror internal lobes' With the widening of these two tracts, the islet
of the postero-internal lobe next became continuous with that in advance.
At this stage there would appear three dentinal tracts: one-for the outer pair
of lobes, a second for the internal and antero-median lobes, and a third as a
circular islet on the postero-median lobe.

The posterior two premolars (Figs. 19, 21) have bilobed crowns, remind-
ing one of the premolars of ruminants. The sudden reduction from the six
lobes of the crown of the molars to the single pair of the crown of the pre-
molars is a remarkable anatomical character. The lobes are pyramidal, and
so far spread apart as to give the crown a greater width transversely. The
summit of the inner lobe forms a crescentoid ridge, embracing the bottom of
the outer lobe. A strong basal ridge bounds the fore and back part of the

crown, and festoons it externally.

80)

In the third premolar the inner lobe is less well developed at its fore part
than in the fourth.

The crown of the second premolar (Figs. 19, 22) is formed of a single
conical lobe, corresponding with the external lobe of the succeeding tooth.
Postero-internally, it presents a feeble rudiment of an inner lobe. The
crowns of the premolars were worn away mostly in a slanting manner poste-
riorly. The exposed dentine in the two lobed crowns became continuous at
the back of the crown.

The molars above described resemble, in construction and in the relative
position of the six lobes of the crown, those of Hyracotherium and Pliolophus,
two extinct genera of pachyderms; described by Professor Owen from remains
found in the London clay, an Eocene formation of the estuary of the Thames.
In both the genera named the last molar is proportionately better developed ;
and in all the molars the postero-internal lobe and the basal ridge are likewise
proportionately better developed. The upper premolars are quite different.
In Hyracotherium the back two premolars have five lobed crowns, and in
Pliolophus the last premolar has a similar constitution,

Too small a portion of the jaw (Fig. 18) containing the teeth above
described has been preserved to ascertain anything of importance as to the
shape of the face. The infra-orbital foramen is situated immediately above —
the interval of the back two premolars.

Measurements from some of the upper-jaw specimens and teeth above

described are as follows:

:
_ Specimens in Plate VI. Figs. 18,19.) Fig. 20.

| Lines. Lines. Lines:
Space occupied by series of six molar teeth...-....-- | 9: 1.5
Space oceupied by true molars ... ........... eaten Aes eas 5 54
Space occupied by three premolars ..........-.-.-..--.-. 32 | Jose
Breadthvorsecond premolar -e. ese See ee) 1. ||..:) sole
Wirdthvor second@premolates c= ream ects. ere reer Ne PP Ee eo. 5
Bréeadthyor third premolar ei seecr cr ss eee eee 1). eae
Wate thao Ghimd) spore lair r parents ee egy erat If hea. a
Breadth os fourth premolar]: seae-- eee eee eee Ea reese Re 14
Width ortourth= premolars «sacs 0t2 oee- ee eeie ae ee Nae ERs ee
Bread hotest mMOlaLeen eee ae eee ene aa 12 14 19
Width ofsirst. molars: 225) (seals te tei oie es a | 24 24 24
Breadth of second molar......-.. SLE ire REI 1S Hc ee rae 2 2 2
Widlthvorsecondsmolarts2)e.- e-em ene ee 24 23 3
Breadthion last molanie.: 52). se. I Nenrte a eens sk yee: : 13 1g 13
Wide totelast molten... 6 sae < a oe ier se ee ae 5) 2 24 24

81

HyYopsoDUSs MINUSCULUS.

A smaller species of Hyopsodus than the one described in the preceding
pages appears to be indicated by a specimen discovered by Dr. Carter in the
buttes of Dry Creek. The specimen consists of an upper-jaw fragment con-
taining the true molars and part of the last premolar, which are represented
in Fig. 5, Plate XX VIL. The teeth differ in no essential character and only
in size. Their comparative measurement with those of H. paulus are as

follows :
Hyopsodus Hyopsodus
minusculus. | paulus.
Lines Lines
Length of space occupied by the last premolar and molars. . 5.4 6. 45
Length of space occupied by the molars........----.----- 4, 4 5.2
PmenmmNOie last PROMOIML 042. .----- reece wee wun snnie sees 1.05 1.4
Width of last premolar.......-..... Dacre ae tee, Hit ge tet | 1.8 2.2
editor mst MOlATa: 2 deh. c 2224 dante sees es scees scene 1.6 1s
VM MC MITS eI OLA <2 eels cP yars/aieisctecis S/x.ctaracueicveld oc nyeimpaieie 2.0 2.4.
eOMPOL SCCOMM MOAT... . 5... be eee ee eee eee eee 1G 2.0
Width of second molar... .- he are eae Seat se eee eee Ie pte ea
eam OnOi MIN OCMOLA. .. 2.06 ok cee yee ewer enone ves $, See, 1.25 | 1.6
NVC OMO te HNIC MOAT =<. oe cle c)se nce sols mare's aise aire neces ae 115%) 2.39

MICROSUS.
Microsus CUSPIDATUS.

The genus Microsus is obscurely determined and is uncertain in its distinc-
tion from the previous genus. It was originally inferred from the lower-jaw
fragment with the back two molars, represented in Fig. 10, Plate VI, at the
same time that Hyopsodus paulus was characterized from the only specimen
then in our possession, represented in Fig. 1 of the same plate. The well-
marked difference in the form and proportion of the corresponding portion of
the jaw led me to view it as pertaining to a different genus from Hyopsodus.
Subsequently I have had the opportunity of examining many and more char-
acteristic specimens referable to the latter, but none which with any certainty
could be ascribed to Microsus.

The jaw-specimen referred to the latter was obtained by Professor Hay-
den on Black’s Fork of Green River. The jaw would appear to be narrower

and weaker than in Hyopsodus. The fragment as seen in Fig. 10, in com-
ial me )

82

parison with corresponding portions of the latter, as seen in Figs. 1.3, 4, 7, is
proportionately of less depth, and at the base beneath the moijars curves
much more upwardly in a backward direction. ;

The teeth, represented in Figs. 10 and 11, are unworn, and they have the
same size and constitution as those of Hyopsodus. In the specimen the con- -
stituent lobes of the crown appear more prominent and their intervals more
deeply angular than in those of Hyopsodus, but this difference is probably
due to difference in age. In all the specimens ascribed to Hyopsodus the
teeth are more or less worn, and only in that attributed to Microsus are they
unworn. Observing, also, that the proportionate depth of the lower jaw in
the different specimens of Hyopsodus holds some relationship with the age
of the animal, as indicated by the extent of wearing of the teeth, I have sup-
posed that the variations observed in the jaw-fragment of Microsus might be
due to the same cause, and that it therefore really pertains to Hyopsodus pau-
lus. Thus by comparison of Fig. 10, representing Microsus, with that of
Fig. 6, representing a specimen of Hyopsodus, in which the teeth are least
worn, the resemblance is observed to be greater than with the other and
older specimens of Hyopsodus.

Comparative measurements of the specimen referred to Microsus with
specimens of Hyopsodus represented in Figs. 1, 3, and 6 are as follows:

° Microsus. Hyopsodus.

Fig. 10. | Fig. 1. | Fig. 3. | Fig. 6.

Lines Lines Lines Lines.
Depth of lower jaw at fore part of last molar....... 24 34 4 32
Space occupied by last two molars ------.--- aeBee 44 41 41 4
Antero-posterior diameter of last molar-....-..-..-- 23 22 21 au
Antero-posterior diameter of second molar... ...-. 21 2 2 2

MICROSYOPS.

An extinct genus of small mammals, to which the above name was given.
was originally founded on several lower-jaw fragments containing molar teeth.
Though classed among the pachyderms, it is not positive that such is the true
position of the genus. The more complete of the specimens upon which it
was characterized indicates a series of six molar teeth following closely after

a well-developed canine. The number of incisors is unknown.

‘

83

In the genus Limnotherium, as established by Professor Marsh, from the
typical species L. tyrannus, the dental formula consists of two incisors, a
canine and seven molars.

Mycrosyorps GRACILIS.

The more characteristic specimen upon which this species was named con-
sists of a portion of the left ramus of the lower jaw, represented in Fig. 14,
Plate VI, of the natural size. The specimen was discovered by Dr. Carter
on Grizzly Butte. Besides the fang of the canine and those of the premolars,
it contains the true molars entire. These are moderately worn at the sum-
mits of the constituent lobes of their crowns, and their triturating surfaces
are represented in Fig, 15 of the same plate, magnified four diameters. The
jaw-fragment retains part of the rough sutural surface of the symphysis, show-
ing that its union was ligamentous with the other ramus. The basal portion
beneath the molars is broken away. Below the premolars it is of mederate
depth and thickness, and soon curves upward with the fang of the canine. The
mental foramen is situated below the second premolar... The fang of the
canine indicates a proportionately larger tooth than in Hyopsodus. It is lat-
erally compressed and curves upward, forward, and outward. The transverse
section is oval with the long diameter directed obliquely forward and out-
ward, and measuring 1.8 line, while the short diameter is 1 line.

The premolars successively increase in size. The first is separated by a
slight hiatus from the canine, and was inserted by a single fang. The others

have two fangs.

The molars have oblong quadrately-oval crowns of nearly uniform size.
They are inserted with two fangs, with the back one of the last molar widened,
as usual in most ungulates.

‘The crown of the molars is composed of two divisions, in addition to
which the last one has a large posterior tubercle. ‘The anterior division of the
crown is smaller than the posterior, and appears of the same form in a more

contracted condition. -EKach division consists of an external crescentoid coni-
eal lobe and an internal rudimental conical lobe or *tubercle, which is placed
opposite the back part of the former lobe. :
The front arm of the anterior crescentoid lobe ends in a thickening in ad-
vance of the antero-internal lobe. The corresponding arm of the better de-
veloped posterior crescentoid lobe terminates at the base of the lobe in front
of it. The back arm of the same lobe forms a slight thickening contiguous

84

to the postero-internal lobe. In the last molar this thickening appears to be
developed into the large tubercle back of the second division of the crown.
Feeble traces of a basal ridge occupy the interval of the outer lobes and the
back of the crown.

Measurements of the lower-jaw specimen of Jficrosyops gracilis are as fol-

lows:

Lines.
Depth of.lower jaw below last molar............-------- oe teins ars cee eee 4
Thickness of lower jaw below last premolar..-.....-...-.-<.-- -=+<+«s5s-eeseee 24 ,
Distance from canine alveolus to back of last molar.-.-.-......-.....-.------- 10
Space occupied by the entire molar series..-.-..-..-. osW abe «2 en 9%
pace occupied by the premolars <5. .2....5--2.- 55> sep -ee ee eee eee 4
Space occupied: by fhewmolars:... 0 Soo... ceeee gee fae 2 eet => 3 ne Se 53
Breadth of tspimolars]) 8222 UENe Soe eee ee ee ae eee : - 13
. Breadth:of' second mmolany: 2 2 o5,5.. soos oh 2. SS cele Sue os eee eee -pSielncea We
Breadth, of third wiglare. 322.0. eet. oe a een eee Peery = 2

The specific name of JZ. gracilis was originally given under the impression
that the remains referred by Professor Marsh to Hyopsodus gracilis pertained
to the same animal. A specimen exhibited to the writer by Professor Marsh
would indicate that JZ gracilis is the same as the animal named by him
Limnotherium elegans. As Microsyops is generically distinct from Limno-
therium, as characterized from the typical species L. tyrannus, the specific
name of the former would be Microsyops elegans.

Another specimen, originally referred to Microsyops gracilis, is represented
in Fig. 16, Plate VI, and-was found by Dr. Carter near Lodge-Pole Trail,
about ten miles from Fort Bridger. It consists of a portion of the left ramus
of the lower jaw, containing the penultimate molar and part of the last one.

The only remaining. entire molar, a view of the triturating surface of
which is given in Fig. 1%, closely resembles the corresponding tooth in the
specimen first described, except that it is a little larger. (The artist has
made it appear different by exaggerating the proportions of the tubercle be-
tween the posterior lobes, and leaving it out altogether in the corresponding
view of Fig. 15.) The remaining portion of the last molar also agrees with
the corresponding portion+in the first-described specimen. ‘The lower jaw is
comparatively deep, and is nearly straight along the base. The fore part
with the symphysis is lost, but it would appear not to have been so shallow
and thick as in the former specimen, which leads me to suspect that it
perhaps belongs to a different animal. The mental foramen holds the same

relative position as in the other specimen. The ridge bordering the fore

85

part of the coronoid process terminates in a tubercle at the fore part of the
moderately deep masseteric fossa.

Another foramen, perhaps not constant to the species, is situated below
the position of the fore part of the first molar.

The measurements of the specimen are as follows:

Lines
rae Olea DELOW Nash, MOAN 3 bce ven tiie Vales Steere sacle eS esi wae 42
Denunot jaw below last premolar’...-22025...-2..5.20 02 ci. 72 = Ree 5 43
Space occupied by last premolar and .molars.....-..---:------.-+--04- ap en a nee 7#
Space occupied by the molars.-.--...--. ---- Se oth SS as ica errs eee 6
Breadth of penultimate molar... ..-. (ober secoc clo nemectceausene eae eto 24
Breadth of last molar .---. OER olae ook o ce es cite Ore Oe ac ne Se Ones tee eee 24

The only specimen of an upper tooth which may, with any probability, be
supposed to belong to Microsyops, is contained in a small fragment of the
jaw, found by Dr. Carter on Dry. Creek. The tooth, apparently a first or
second molar, is represented in Figs. 19, 20, Plate XXVII. The crown is
not so square and is proportionately of less breadth fore and aft than in the
corresponding tooth of Hyopsodus. It narrows inwardly more than in the
latter, the reduction taking place posteriorly, where the crown is concave.
The constitution of the tooth is nearly as in Hyopsodus, and ‘the principal
difference is found in the condition of the postero-internal lobe. In Hyopso-
dus, this is a reduced form of the lobe in advance, being crescentoid. In the
supposed tooth of Microsyops, the postero-internal lobe appears as a conical
tubercle springing from the base postero-internally of the larger crescentoid
lobe in front. In Hyopsodus, the postero-median lobe is a simple cone, but
in the tooth in question it is pyramidal.

The antero-posterior diameter of the crown externally is 1.6 lines; inter-
nally, 1.2 lines; the transverse diameter anteriorly is 2.2 lines.

.

UNDETERMINED.

Fig. 12, Plate VI, represents a specimen found by Dr. Carter on Henry’s

ork of Green River. , consists of a lower-jaw fragment with the last pre-
Fork of G R it ts of a lower-jaw fragment with the last |
molar and the fangs of the molars of a mature animal of undetermined
character, but, from the form of the remaining tooth, evidently allied with
Hyopsodus. The premolar, Fig. 13, is unlike the corresponding one of the
latter genus, as seen by comparing it with Figs. 5 and 8, but resembles the
true molars. Suspecting that it might be a last temporary molar, notwith-

standing its shghtly worn condition and its association with the full series of

86

molars in functional position behind, I examined the jaw beneath, but found
no trace of a successor,

The portion of jaw is of more uniform depth, and the base less convex
than in Hyopsodus. It is also more impressed and concave below the position
of the back molars. The space occupied by the molars is about equal to
that in the smaller specimens of Hyopsodus.

Perhaps the specimen may pertain to Microsus, or probably may belong to
agenus different from either of those just named. Its measurements are as

follows : S
Lines
Space occupied by the last premolar and BOSH Si sy eee Lajeeds ese). 73
Space’ occupied by the molars wai. waste" sae eee ee eee me. 54
Depth of jaw at fore part of last molar -- J. 22.2. 0250)... 222-2. 2 ee er 34
Depth of jaw at-last.premolars ... 2.25%... le beds ca de - ce ee oe 4
‘Antero-posterior diameter of: last molar. ....2.-.-2..-) 72020-2220 21
es

Antero-posterior diameter of last premolar- 22-22-22". -2-.-<.--- 9-4 oe

NOTHARCTUS.

NOTHARCTUS TENEBROSUS.

A small extinct pachyderm, referred to a genus with the above name, judg-
ing from the anatomical characters of the specimen upon which it was founded,
was probably as carnivorous in habit as the raccoon and bear. ‘The specimen
to which I allude, represented in Fig. 36, Plate VI, consists of the right
ramus of a lower jaw with most of the teeth. It was discovered during Pro-
fessor Hayden’s exploration of 1870, on Black’s Fork of Green River. I at
first viewed it as pertaining to a carnivorous animal, and thus referred it; but
the anatomical relations of the specimen with those of remains of other ani-
mals which have been found in association with it have léd me to view the
jaw as having belonged to a pachyderm. The ramus of the jaw contained a
series of seven molar teeth, all of which are preserved except the first pre-
molar.. A well-developed canine occupies a position immediately in advance
of the molar series, and the incisors filled the interval between the canines of
the two sides. Thus the teeth. of the lower jaw of Notharctus form an un-
broken arch. The incisors are lost from the specimen, and the condition of
the alveoli is such that the number of them cannot be ascertained.

The canine tooth of Notharctus in its relative position, form, and propor-
tions resembles that of ordinary carnivores. It curves from the opening of

the alveolus slightly backward with an inclination outward. The crown is

87

conse eal elevated from an. increased protrusion of the fang, such as is
observable in carnivorous animals past maturity. The fang is gibbous and
feebly curved.

The molar teeth, represented in Fig. 37, magnified two diameters, are con-
siderably worn in the specimen, all of them exhibiting exposed tracts of den-
tine, due to the wear of mastication.

The four premolars successively increase in size, and are inserted by a pair
of fangs, except the first, im which they appear to have been connate. The
crowns of the premolars from behind forward exhibit a successive reduction
to a simpler form from that of the molars,

The crowns of the second and third premolars, and no doubt also that of
the first one, which is lost from the specimen, have the conical form of the
corresponding teeth in carnivores, though they appear less prominent, due to
their worn condition. They are slightly thicker behind than in front, and a
basal ridge internally forms a slight offset or heel posteriorly, and a still feebler
one in the third premolar anteriorly.

The crown of the fourth premolar is intermediate in char acter with those
in advance and those of the molars behind. Its fore part consists of a conical
lobe like the crown of the anterior premolars; its back part is a broad heel
corresponding with the back lobe of the molars. The summit of the princi-
pal lobe is extended obliquely inward and backward and is continuous with
the inner basal ridge of the crown. Externally; the latter is embraced by a
basal ridge. i

The crown of the second premolar is worn away along its posterior slope ;
the crown of the third to a greater degree in a corresponding position, and
also to a less degree along its anterior slope.

The molars are nearly alike in form and constitution, and are inserted with
two fangs. The crown of the molars bears a certain degree of resemblance
in construction to those of the raccoon, and in a Jess degree to those of the
opossum, but certainly enough resemblance to both to indicate a relation
which is not merely accidental.

In the unworn condition of the lower molars of Notharctus, the crown
would appear to be composed of two divisions. The anterior division pre-
sents three prominent points continuous in an acute crescentoid ridge. The
principal point js central and external, the second is nearly as well developed
and internal, and the third point, feebly developed, occupies the fore part of

oT)

the crown ‘The posterior division presents two elevated points, conjoined in
a crescentoid ridge. ‘The anterior extremity of this ridge joins the front
division of the crown. Its more elevated point is external and posterior, and
its less developed one occupies the postero-internal corner of the crown. A
basal ridge incloses the crown, except internally.

Each division of the crown of the molars incloses in the arms of its+cres-
centoid ridge a depression, which is largest in-the posterior division. The
crown of the last molar is more prolonged backward than the others, arising
from the greater degree of development in this direction of its posterior
division. :

In the worn condition of the molars, as seen in Fig. 37, the crescentoid
ridges of the divisions of the crown have been so much abraded as to expose
broad crescentoid tracts of dentine continuous on the two divisions of the
crown.

The rami of thelower jaw of Northarctus appear to be co-vssified at the
symphysis, and the specimen under consideration was broken off just to the
left of the latter. The chin is narrow and convex transversely, and it forms
a nearly straight or slightly convex slope of about 45°. The body of the
bone is nearly of uniform depth; the relation of depth to length being much
greater than in the raccoon and more in proportion with the measurements
in the hog and peccary. The outer face of the body is nearly vertical. ‘The
base is thick and slightly convex fore and aft. _Near the middle, directed in-
wardly, it exhibits a strong impression for muscular attachment.

The angle of the jaw, the back, border of the bone, and the coronoid pro-
cess are lost. The outer face of the ascending portion of the ramus ‘is
depressed into a masseteric fossa extending nearly or quite to the base, but
shallow compared with that of ordinary carnivores. ‘The condyle is remark-
ably short, and resembles that of some of the monkeys more than that of ordinary
pachyderms. It is transversely oval, with the breadth less than twice the
fore and aft diameter, which is directed obliquely from without inward and
backward. The articular surface is transversely conyex and inclines more
outwardly than inward.

The form of the condyle clearly indicates more varied movements in the
jaw than exists in the carnivora, and would rather be favorable to the proper
reduction of the food of an omnivorous animal.

A mental foramen occupies a position about midway between the third

89

premolar and the base of the jaw. Two small foramina are situated below
the position of the first premolar.

In the American Journal of Science for 1871,°Professor Marsh has
described the lower jaw, with teeth, of a small pachyderm, under the name of
Limnotherium tyrannus, which would appear at least to belong to the same
genus as’ the former. The specimen was found near Dry Creek, Wyoming.
According to the description and measurements, the jaw nearly accords with
that of Notharctus tenebrosus. 'The teeth in an interrupted series consist of
two incisors, a canine, four premolars, and three molars. If we suppose
Notharctus to have two incisors, the number, character, and relative position
of the teeth agree in both. In Limnotherium ‘the first and second premolars
are observed to have a single fang. This character alone would be insufficient
to distinguish a genus, and, perhaps, would hardly be regarded as a specific
character. The description of the molars of Limnotherium would apply to
those of Notharctus. ;

- The measurements of the lower-jaw specimen of Notharctus tenebrosus are

as follows:

Lines.
iheneth of jaw from condyle to incisive alveoli....-........--...--.------. e+. 30
Menumon jaw pelow lash molar... 25... 22. 622.2. cea eas ee ee ce eens 53
Denn onjaw below last premolar . 2. ---.-< =n -nn- een eee ele ees ene ceen eet 6
iLeinetthh: Of SDS ees ee taRaHs aps ee 8
LV vege vETEUE) (OEE CCKDTENG LEVIN Bis Ce pane aS eo 3
AMinero- posterior diameter of condyle ...-.- 0... 2. ese eee ee ce eee eee ee een 2
enmeth-of dental series... ...-.--.6---.2-26 2020 ee 5 OSI AST fan re eee AT _ 193
Wensih of space occupied by the molar series....-........-.-.---------.--+-0s 16
Tength of space occupied by the true molars .......2..-...--0---. 2-2 chee eee ee 83
MERCI Ol CAMING at DASE OF CLOWN, 0.06 22 se ee nls eee eee ene wees 13
honed diameter of second premolar......-..--..---.2-2.2-- seen eee ee- 14
Minanswexrse diameter of second premolar .-.-.....-..---..-2..ceenasenecccaces 3
Fore and aft diameter of third premolar. ..... . Rebate ow ciutae sey dee ameter ieaiald sees 13
iiiiswersedinnerer Of bhind premolars... 5 2... -- es ee cee eee eee ee eee wee 14
Nore and att diameter of fourth premolar:.............-..'...-00e- ence eee e eens 2
MitMswenseraiameter Of fourtin premolar... -.-. 2.0.22 5... eee we lee c ee eens 14
Fore and aft diameter of first molar ........-...... So. Site: tection os ete se. 23
Transverse diameter of first molar... . - REE EE pene tao Oye meng $e gS | 2
Great diameter Of Second MOlar......-.. 2 ..-- ee sees eee ee eee eens 23
MrAMsVetse CiameLeror SECONG MOLL... --. -l..6 2 tare aces eee dese ees eee ces 2
Roremmndratirarameter on hurd molar. . io.) .2escic oc dije ak see ds accedeeceesueees 34
AMS VeESeMULUMener OnsmMG MOR 4 s4 <2 oe ee cae ee we cine cee cede ee eee eee 2

In many respects the lower jaw of Notharctus resembles that of some of
the existing American monkeys quite as much as it does that of any of the
living pachyderms. Notharctus agrees with most of the American monkeys

126

90

in the union of the rami of the jaw atthe symphysis, in the small size of the
condyle, in the crowded condition of the teeth, and in the number of incisors,
canines, and true molars, which are also nearly alike in constitution. Nothare-
tus possesses one more premolar and the others have a pair of fangs. The
resemblance is so close that but little change would be necessary to evolve
from the jaw and teeth of Notharctus that of a modern monkey. The same
condition which would lead to the suppression of a first premolar, in continu-
ance would reduce the fangs of the other premolars to a-single one. This
change, with a concomitant shortening and increase of depth of the jaw, would
give the characters of a living Cebus. A further reduction of a single premo-
lar would give rise to the condition of the jaw in the Old World apes and man.

HIPPOSYUS.

-H1PPOSYUS FORMOSUS.

Several small fragments of jaws with teeth, discovered by Dr. Carter in
the vicinity of Fort Bridger, are suspected to belong to a different genus of
pachyderms from any of those indicated in the preceding pages. One of the
specimens consists of an upper-jaw fragment with the molars in a mutilated
condition. ‘The first and second molars are the best preserved, and are rep-
resented in Fig. 41, Plate VI, magnified three diameters. The first one is
nearly entire, but in the figure is represented in a restored condition by the
addition of the antero-external angle marked by the zigzag black line.

The upper molars bear a general resemblance in the construction of their
crowns to those of Anchitherium. The outer lobes are like those in the lat-
ter, but have their outer buttress-like ridges proportionately thicker. The
antero-internal lobe is larger than that behind and conjoins it. In Anchitherium
the inner lobes are nearly equal and isolated from each other. The antéro-
median lobe, as existing in Anchitherium, in the present fossil is completely
connate as part of the antero-internal lobe, and the postero-median lobe of
the former is nearly obsolete, or appears as a mere rudiment in Hipposyus.
A strong basal ridge incloses the crown in front, behind, and internally, but
is absent in Anchitherium in the latter position.

The measurements of the specimen are as follows:

Lines.

)Spaceoccupied by the three molars; mes cee ee i a
Bread Ghgolstnstam Olas See eee et At A ee Ee 23
Breadthvorsecond molar’ 28. thse Os eee ae ne ae ete te eet ee 23

'Breandthvotethingdsino aries 4. oe eee ea eee Ee eee, oo eee 23 -

91

The other specimens accompanying the former, and suspected to belong to
the same species, consist of fragments of three lower jaws, containing each
one or two molar teeth. One of the specimens contains the first and second
molars and the remains of the last one. The portion of jaw is like the corre-
sponding portion in Notharctus, but is thicker and the teeth are stouter. The
teeth are considerably worn, as represented in the view of the triturating sur-

face of the second molar in Fig. 38, Plate VI, magnified two diameters. The
crown is oblong square, and consists of two divisions, each of which, in the
unworn condition, presented. an acute crescentoid summit In the abraded
condition the divisions present two broad, semi-lunar tracts of dentine con-
tinuous with each other. The tracts embrace, internally, shallow enameled
recesses, of which the posterior is much the larger. The contiguous horns
of the tracts are continuous upon a tubercle at the inner part of the crown
just in advance of the middle. The posterior horn of the posterior crescent
is likewise continuous, with a tubercle at the postero-internal angle of the
crown. Externally the latter is bounded by a basal ridge, and an element of
the same occupies the postero-internal angle of the crown.

Measurements of the specimen are as follows:

‘Lines.
Wepumot jaw below the middle molar .... 22.2.2... 52-06%. oR et a Ee 5S
Precmccipleds Dy Le PALE MOLATS. . 2... 23 sa ee ae fom Se eee nee eee eee eee 9
Breadth of crown of first molar .-...--..- APS PSE eo eae Bia Sa lehman ee 24
SMMEOInC MONON LOLS MOAR ..a2- 22-2. ce «ec ae whee ein ee teen eee ane tena ee 2
PecOuieOMmerowil Of Second mOlar. 2.25 2... 02. oe le eee eee eee cae 3
um reeCuONmm OF SECONG MOlais. =. - hed. =. 6 ee tem ae teense cee me ne ceenen enunay 24

A second specimen consists of a nearly corresponding portion of another
jaw containing the first and second molars. The jaw-fragment is of greater
depth than in the former, but otherwise is about as robust, and the teeth are

nearly of the same size. The measurements are as follows:

. 5 Lines.
Pepirontan MEOW ING Ce MOlAT 62.5. foe oo ee ee ee cet eel geese 53
“SRE TN CHE CLO OATS ATC) Ch: On ie le eae 22
Mrcmomerownm Of Arst mOlar.'.--.-.--....-.---. 5. l.22..-: Loe Enns oe oA Pea a Pa 24
re aGinivOuerowne Oh SeCONd MOlar..-4-- 2:-. 2-2-2) ene. mee cg ate ne esos bene 23
MindiMmomerowm Ol SCCOMM MOlAr- 22)... 2. 6e ee ksh ee we ee See ee SRE

Two additional specimens consist of portions of both rami‘of the lower jaw
of a younger animal than the preceding, but only one contains a single tooth,
the first molar, which is represented in Fig. 39, Plate VI, magnified two
diameters. The rami of the jaw are of more slender proportions than indicated

92

hy the fragments above described, but are nearly as thick; and the retained
tooth is of the same size and form as its fellow in the fragments of older Jaws.

One of the rami contains the fangs of the complete molar series, together
with part of the canine alveolus, which is close to the former. The number
of premolars I cannot determine with certainty. If three, the first of the
series is larger than the second, and has its fangs more widely separated. If
the number is four, the anterior two have each a single fang.

Perhaps the latter is the true condition, which accords with that attributed
to Limnotherium by Professor Marsh. ;

Three vasculo-neural foramina are situated at the outer part of the ramus:
one just back of the position of. the canine alveolus; a second below the
interval of the back two premolars, and the third beneath the first molar. In
the opposite ramus the latter is below the last premolar, and it occupies the
same position in the former two specimens.

The first molar tooth retained in one of the rami agrees with the descrip-
tion of those in the older jaw-fragments. Fig. 38, Plate VI, represents the
right second molar much worn; and Fig. 39 represents the first left molar
in a much less abraded condition. '
Measurements from the two rami of the lower jaw just described are as

follows :

Lines
Space occupied by the premolar and molar series ......-......-----.--..------ 164
Space occupied by the: molar series-=-=-- s-.--22-22- 22 - eee ee ee er 9
Depth of jaw, below the premolarse=s.-- -- ==> 26 ee ees Pe oS, - 5
Depth of jaw below the middle molar: \2-...22-<5-— Ssece see 2 ee ee 43
Breadth.of the first molar. 2.05 ois <3) 55 cies ge nn as ee 3
Width! of thehirstemolanic ss eee se rene eee eee OMe See aae ae a 24

ered by Dr. Carter on Grizzly Buttes. It appears to be a first upper true
molar of Hipposyus formosus, and is scarcely worn. It was found isolated
and unaccompanied by any other pieces which could be reasonably attributed
to the same animal. From the comparative perfection of its crown, its con-
stitution is more evident. It resembles in miniature the corresponding teeth
of Anchitherium, and differs especially in the less proportionate development
of the median lobes of the crown, in the greater degree of production of the
basal ridge, in the more intimate union of the inner lobes ard their more
sloping character externally, in the more isolated condition of the postero-
median lobe from the contiguous inner one, and in the more wrinkled condi-

93

‘tion of all the lobes approaching the base ‘of the crown. The transverse
diameter of the latter is $ of an inch; its fore and aft diameter externally 4

of an inch. .
HIPPosyUSs ROBUSTIOR.

A lower-jaw fragment containing a single tooth, obtained by Professor
Hayden on Henry’s Fork of Green River, apparently indicates a more robust
_ species of the same genus as the former. I at first attributed the specimen
to a Species of Notharctus, with the name of JV. robustior, but a comparison
of the tooth, represented in Fig. 40, Plate VI, with those of Aipposyus formo-
sus, Figs. 38, 39, will at once suggest the probability of its pertaining to a
larger species of the latter genus. Perhaps the specimen may belong to a
more robust individual of the same species.

The jaw-fragment is too imperfect to ascertain anything in regard to its
anatomical characters other than its thickness. Below the second molar it is
4 of an inch thick; in the specimens attributed to H. formosus it ranges in the
same position from 34 to 34 lines in thickness. The second molar tooth is
34 lines broad and 24 lines wide.

Order Proboscidea ?

Large quadrupeds with five toes to the feet; molar teeth with transverse
ridges; femur without a third trochanter; nose prolonged into a cylindrical

trunk or proboscis.

UINTATHERIUM.

While encamped in Dry Creek Cafion, forty miles to the east of Fort
Bridger, Drs. Carter and Corson spent a day in traversing a most desolate
region to some buttes about ten miles farther to the east. They returned to
camp after sundown laden with fossils, among which were the remains of the
largest animal which had yet been brought to our notice from the Bridger
Tertiary beds. ‘These remains consist of the cranial portion of a skull with
fragments of both jaws attached to the same matrix, a nearly complete arm-
bone, and fragments of other limb-bones. A notice of these remains, attrib-
uted to a pachyderm with the name of Uintatherium robustum, was com-
municated in a letter to the Academy of Natural Sciences of Philadelphia,
and was published August 1, 1872. ;

_ On the previous day to the discovery of the remains of Uintatherium,
while engaged in the search for fossils along the buttes, about a mile to the

94

east of our camp, Dr. Corson called my attention to a large tusk which he had
found mingled with some drift-pebbles that had fallen from the top of the:
butte. In the tusk I thought I recognized the canine of a large carnivore
related to the extinct saber-toothed tiger of Brazil. On further search, we
found a portion of the opposite tusk, an isolated molar supposed to belong to
Uintatherium, another of Paleeosyops, and the scale of a ganoid fish.

In the same letter above mentioned, the large tusks were described and
attributed to a carnivore with the name of Uintamastix atroz.

On our return to Fort Bridger, while examining and discussing the Saute
collected in our expedition, the question arose whether the large tusks did not
pertain to the same animal I have named Uintatherium. Our specimen of
the skull of the latter did not assist the determination of the question, as the
facial portion was wanting, excepting small fragments of the back of the jaws
containing the last molar teeth. While admitting the probability of the tusks
pertaining to Uintatherium, from their being so unlike those of any known
pachyderm, and from their near resemblance, both in form and size, to those
of the great extinct Machairodus of Brazil, I thought the weight of evidence
was in favor of their reference to a carnivore. The finding of a molar tooth
of Uintatherium in association with the tusks appeared to me not to outweigh
this evidence any more than the association with them of a molar of Paleo-
syops. .

Professor Marsh has published several notices in the American Journal of
Science of the remains of large mammals from the Bridger Tertiary forma-

tion, which appear to be related with Uintatherium.

In June, 187 1, he reported the discovery of bones of a large animal which
he referred with doubt to Titanotherium, with the name of 7. anceps. From
somé additional remains, in a foot-note of July 22, 1872, he refers them to a
proboscidean under the name of Mastodon anceps. This is corrected in an
erratum of August 19, referrmg the animal to a new genus with the name .
of Tinoceras anceps. September 21, he published a notice of a new species
with the name of Tinoceras grandis, founded on portions of a skull and teeth,
&e. Of this he observes, ‘The skull is proportionately very small, and indi-
cates one of the most remarkable animals yet discovered. It supports a pair
of short horns, and has also two powerful tusks, which, m size, shape. and
direction, resemble the canines of the walrus.”

More recently, September 27, Professor Marsh has published a ‘notice of,

some remarkable fossil mammals,” which are referred to two species of a new

95

genus with the names of Dinoceras mirabilis and D. lacustris. Of the skull
of this genus, he observes that it presents a most remarkable combination of
characters. ‘‘It is wedge-shaped, elongated, and quite narrow, especially in
front, and was armed with horns and huge decurved canine tusks. The top
of -the skull, moreover, is deeply concave, and has around its lateral and pos-
terior margins an enormous crest. . On the frontal bones, above the orbits,
and in advance of the lateral crest, there is a pair of very large horn-cones,
just behind and above the canines. These are directed upward and outward,
and their summits are obtuse and nearly round. They are solid, except at
the base, which is perforated by the upper extremity of the canine. Near
the anterior margin of the nasals there is still another pair of horn-cones,
which are near together, and have obliquely compressed summits. The nasal
opening is small. The premaxillaries are slender and without teeth. The
upper canines are greatly elongated, slightly curved, and compressed longi-
tudinally. The lower portion is thin and trenchant.- Behind the canine is a
long diastema, followed by a series of six small teeth. The molars have their
crowns composed of two transverse ridges, separated externally, and meeting
at the inner extremities. The skull measures about 284 inches long and 83
inches in width over the orbits. The canine is 94 inches in length below
the jaw, 64 millimeters in longitudinal diameter at base, and 25 millimeters
in transverse diameter. The last upper molar has an antero-posterior diameter
of 36 millimeters.”

It appears to me that the brief description of the skull and molar teeth of
Dinoceras applies so closely to the corresponding parts of Uintatherium as
to render it probable they are of the same genus. The description of the
tusks of the former also.equally well apply to those of Uintamastix, so as to
lead me to suspect that this may likewise be the same as Uintatherium. It
is probable, too, that should the latter not be the same as Dinoceras it may
prove to be the same as Tinoceras, or perhaps the Eobasileus s. Loxolophodon
of Professor Cope.

The characters of Uintatherium, as expressed in the material at our com-
mand, are so peculiar and unlike those of any other known animal as to ren-
der its ordinal affinities obscure. From the form and constitution of the
molar teeth alone, I should have viewed the genus as pertaining to the odd-

_toed pachyderms. If the remains noticed by Professor Marsh under the
name of Dinoceras belong to the same animal, the presence of horns in pairs
to the head would render such a ‘reference improbable. Professor Marsh

96

observes of Dinoceras and the related Tinoceras, that they have the vertebral
and limb bones very similar to those of recent proboscideans, but refers them
to a new order with the name of Dinocerea. —

The form of the thigh-bone and the short tarsal bones of Uintatherium
would appear to indicate limbs and feet most nearly constructed like those of
the elephant. I have provisionally placed the animal in the order of Probos-
cidea, leaving to Professor Marsh the determination of its true position from

the more abundant materials at his command.
UINTATHERIUM ROBUSTUM.

The remains which are specially to be regarded as characteristic of the
animal above named,-and from which it was originally indicated, consist of a
mutilated cranium, to the matrix of which there adhered portions of both
jaws, containing all the last molars and an isolated molar. A nearly com-
plete humerus, together. with some less well preserved specimens found in
association with the former, are supposed to have pertained to the same --
individual.

A small fragment of the upper jaw, containing the last molar tooth, is rep-
resented in Fig. 8, Plate XXV. The tooth, also represented in Figs. 6, 7,.
of the same plate, and Fig. 30, Plate.X XVII, has the crown composed
of a pair of wide pyramidal lobes projecting from a broad expanded base.
The lobes extend across the crown, conjoining internally and diverging ex-
ternally in a V-like manner. They project at their outer extremities in promi-
nent points, and also form together a prominent point at their conjunction
internally. The outer extremity of the anterior lobe is the most prominent
of the three points of the crown. The outer extremity of the posterior
lobe is the least prominent of the three points, while that at the conjune-
tion of the lobes is scarcely more so. The acute summits of the lobes
between the points are transversely concave, and are worn off on their anterior |
slope so as to present narrow tracts of exposed dentine. The posterior slope
of the lobes is slightly concave; and the valley between them is triangular,
and opens outwardly. |

From the posterior slope of the inner part of the back lobe of the crown
there projects a rounded tubercle about half-way between the basal ridge and
the pointed conjunction of the lobes. A second rounded tubercle occupies
the entrance of the triangular valley between the lobes.

A stout basal ridge embraces the crown in front and behind, and.in a

oy

reduced condition continues interruptedly on the inner and outer parts. In
’ outline the base of the crown is ovoidal, with the narrower extremity corre-
sponding with the outer part of the anterior lobe. The tooth is inserted by
a pair of fangs widely compressed, conical, and convergent internally. The
transverse diameter of the crown of the last upper molar is 20 lines; its fore
and aft diameter is nearly 18 lines. The description of the upper molars of
Dinoceras mirabilis, and the size of the last one, as given by Professor Marsh,
so well apply to the tooth above described as to lead me to suspect that the
animal so named is the same as Uintatherium robustum.

The fragments of both sides of the lower jaw of the latter, represented in
Fig. 11, Plate XXV,and Figs. 32, 33, Plate XX VII, contain the last molar tooth,
also represented in Figs. 9, 10, of the former plate, and Fig. 31 of the latter.
The tooth has an oblong square crown, rounded at the corners and moderate ly
constricted at the middle laterally. It is inserted in the jaw by a pair of
‘wide, compressed conical fangs.

- The crown is composed of three lobes, with oblique intervening valleys,
which receive the pair of lobes of the corresponding upper tooth when closed
upon the lower one. ' ie

The anterior lobe forms nearly half the crown, and rises internally in a
point, which is the most prominent part of the tooth. The front and back
surfaces are sloping, and the former is transversely concave, and bounded by
a short, oblique basal ridge. The inner and outer surfaces of the extremities
are convex, and extend to the bottom of. the crown. The acute summit
curves downward and outward from the inner point. It is worn off on the
posterior slope with a more forward direction externally, and exhibits a nar-
row tract of exposed dentine. The prominent point.of the inner extremity
is notched just below the summit postero-internally.

The posterior and middle lobes of the crown are nearly of the same size
and prominence. The posterior lobe is separated from the anterior lobe
internally by a deep, angular notch, and diverges from it externally. It
forms the posterior convex surface of the crown, and has an anterior sloping
surface defined from it by a ridge curving from the inner side backward and
outward, and then becoming continuous, with a basal ridge sweeping down-
ward to the bottom of the middle lobe of the crown externally. The middle
lobe appears like an ovoidal wedge introduced from the outer side, and sepa-
_ rating the anterior and posterior lobes. Its summit is worn off with a slight
posterior slope, and exhibits an exposed tract of dentine.

13G

98

A thin, inconspicuous basal ridge occupies the inner half of the back part
of the crown; a thicker festoon extends from the summit of the posterior
lobe externally to the bottom of the middle lobe; and a short, prominent
ledge occupies the middle of the front of the crown.

The fore and aft diameter of the crown of the last lower molar is 14 inches;
the transverse diameter in front is 14 lines; behind, 124 lines.

Associated. with the other specimens referred to Uintatherium, there was
found the isolated tooth represented in Fig. 12, which I suppose’to be a first
upper molar. It has the same constitution as the last upper molar above
described, but is smaller. In the present condition of the crown, the poste-
rior lobe is more prominent than the anterior, and it exhibits a broad horseshoe-
shaped exposed tract of dentine extending upon the summits of both lobes.
The dentinal surface is concave from side to side, and inclines forward. The
outer extremity of the anterior lobe, broken in the specimen, is considerably
thicker than that of the posterior lobe. Back of the inner conjunction of the
lobes, just below the summit, the rounded tubercle is visible, such as exists
in a corresponding position in the last molar. It is worn so as to exhibit a
small circular islet of dentine.

The basal ridge, as in the last upper molar, is thick in front and behind,
but feeble upon the inner and outer sides. ;

The first molar was inserted by a pair of fangs. The antero-posterior
diameter of the crown is 16 lines; the transverse diameter at the hinder lobe
is 154 lines. :

The upper molars of Uintatherium above described bear considerable
resemblance to the last upper molar of Lophiodon parisiense, as represented —
in Fig. 8, Plate XVII of Gervais’s Paléontologie. They differ especially in
the absence of the offset from the middle of the anterior part of the front lobe |
of the crown. .

The upper molar teeth, attributed by Gervais to L. parisiense, represented
in his Figs. 3, 4, so nearly resemble the corresponding teeth of Uintatherium
and so decidedly differ from those of Lophiodon, as characterized from the -
typical species L. issedense, that it may be questioned whether it belongs to
the same genus. The characters presented by the teeth referred to L. parisi-
ense, are sufficiently distinct and well marked to consider them as indicating
a genus differing from Lophiodon and Uintatherium, and probably more nearly

related with the latter than the former.

99

The cranium of Uintatherium, represented in Fig. 1, Plate XXVI, is of
remarkable form and unlike that of any other known animal. The specimen,
though much mutilated, is yet sufficiently well preserved to give us some
notion of the peculiarities of the skull. ;

The top of the cranium presents a deep basin-like concavity separated on
each side from the temporal fossee by a wide projecting crest. The entire
extent of this cannot be determined from the broken condition of. its edge in
the specimen, but on one side it projects obliquely outward and upward for
three inches beyond the inner surface of the temporal fossa. Posteriorly, the
crest is continuous with a thick broken border extending across the top of
the occiput so as to make it appear as if the lateral projections of the
cranium were continuous behind. The depth of the supra-cranial hollow in
the specimen is upward of several inches, and was, no doubt, greater in the
complete skull.

The témporal fossa is a long deep concavity overarched by the wide lateral
erest separating it from the supra-cranial hollow. Its lower part spreads out-
wardly on a broad ledge extending from the lateral occipital border forward’
upon the upper surface of the zygomatic root. This ledge resembles the
long extension backward of the zygomatic root in the bear, and in like man-
ner it projects over the auditory archway and the contiguous processes.

From the fractured condition of the specimen, I am unable to ascertain the *
position of the squamous suture, and this may be said also of other sutures.
The temporal surface as formed by the squamosal plate and the neighboring

portion of the parietal is pierced with a number of large. vascular foramina.
The occipital surface is broad, and it slopes inwardly from above to the occi-
pital foramen.

The large condyles project strongly backward and downward, and are not
in the least degree sessile, but.well defined from the occipital surface by a
deep groove. Their articular surface is broad, being within a fourth as great
as the depth, and the flexure near its middle appears less pronounced than
usual. The articular surfaces are not prolonged below on the basi-occipital,
and the condyles in this position are separated by a deep notch twenty lines
from each other. |

The basilar process is broad and thick, and moderately tapermg. Its under
surface is transversely convex, especially anteriorly. On each side of the

middle it presents a broad rough eminence for muscular attachment.

100

The relative positions of the paramastoid and mastoid processes, the audi-
tory archway, and the post-glenoid tubercle are nearly the same as -in feline
animals, but here the resemblance ceases.

The paramastoid process is a comparatively slight roughened eminence,
situated just above and external to the position of the fore part of the con-
tiguous condyle. It is separated from the mastoid process by an archway
directed inward and forward to .the space usually occupied by a tympanic
bone, but which in the specimen is filled with the matrix of the fossil.

The mastoid process, though much broader and longer than the paramastoid,
does not project so much downward as the occipital condyle. It is semicir-
cular below and roughened, and is compressed from without inwardly. Its
outer surface presents a median fossa at the base.

The auditory archway expands outwardly in a funnel, and’ below is
partially contracted, by a short ledge, a process of the tympanic, pRojeciane
from the mastoid process. :

The root of the zygoma is of great strength, and has, projecting downward
from it, a post-glenoid tubercle of extraordinary size. The process is 24
inches in width, and projects externally in a rounded knob. Its lower part
forms a slightly irregular flat surface, just above which, the tubercle is 14
inches thick. Its inner extremity slopes upward and inward.

The glenoid articulation is transverse, and its surface straight in this direc-
tion. Upon the post glenoid tubercle the surface is vertical until it curves
forward and upward to the anterior edge of the zygomatic root. «Its forward
extension is about equal to that downward. The glenoid articulation is evi-
dently adapted especially to a hinge-like motion, though- not so restricted as
that of carnivores.

Measurements derived from the cranial specimen of Uintatherium are as

follows :

Inches
Breadth of the cranium at the outer part of the post-glenoid tubercles. ..-..-.---- 10
Breadth of the cranium at the mastoid processes.......--.----------- Bese: 14
Width of the basi-occipital in front of the occipital condyles..-.....-- oe See 23
Breadth of the eccipital-condyles tosether-. -5252---.------. s.--.-.- 2-2 6
Breadth of each condyle: ---2. 2 2-2--2- ist a a iceiaihse, oie ese osc ss 4 or 24
Depth-ofeach condyle2; 23) 2.F SR ee ee te ee Sag 3
Distance between the condyles or breadth of the occipital foramen.....---..--.. 24
length of the temporal fossa fore and aft <2. ....-2-.-2--.-si..s-.5. 0. sees i
Breadth of cranium between the temporal fossz where Leen about’'.-.~ -Seeae 44

Depth of cranium from bottom of supra-cranial basin to basi-occipital, about .... 43

101

The lower-jaw specimens of Uintatherium are represented in Fig. .11,
Plate XXV, and Figs. 32, 33, Plate XX VII. Both contain the last molar, and
the better-preserved one also contains the fangs of the preceding molars and
the last premolar. The space occupied by the molars is 4 inches, which
appears small in relation with the size of the animal. The space which was
occupied by the second molar is nearly as broad as the last molar. The
crown of this measures 14 inches. The space which was occupied by the
first molar is little more than three-fourths of an inch, thus showing a great
difference in the size of the first, compared with that of the succeeding
molars. ,

The body of the jaw is of robust proportions. Its depth beneath the fore
part of the last molar is 34 inches ; its thickness just above the rounded base
is nearly 14 inches. A strong obtuse ridge sweeps from the root of the coro-

_ noid process downward and forward along the base of the jaw beneath the”

position of the molars. : .

Back of the position of the latter, the jaw bears more resemblance to the
corresponding portion in the great felines than if does to that of ordinary
pachyderms. .

The coronoid process is a broad curved plate rising immediately in advance
of the condyle, as in the lion. As in the latter, likewise, it is impressed ex-
ternally with a deep masseteric fossa extending below on the body of the
bone, but becoming more abruptly shallow approaching the base. |

The entfance to the dental canal is nearly on a line with the alveolar bor-
der, 24 inches above the base of the jaw.

The condyle is a transverse convexity 24 inches in breadth, and rather
more than an inch in width at the middle. It is narrowest internally, the re-
verse of the condition in the lion.

The breadth of the jaw back of the molars is estimated to be about 5
inches; the breadth of the coronoid process at base is about 3 inches.

The specimen of a mutilated atlas, represented in Fig. 2, Plate XX VI, and
Fig. 34, Plate XX VII, supposed to belong to Uintatherium, was found by
the writer on the buttes west of Dry Creek Cafion. It accords in size with
the cranium of Uintatherium above described, and fits the occipital con-

dyles as well as the bone of one individual might be expected to adapt itself

to that of another.
The atlas is. very unlike that of any ordinary familiar animal. While it is
much smaller than that of a mastodon, it includes a canal of even greater

*

102

capacity. Unlike that of the animal just named, it is quite cireular, and
about 34§ inches in diameter. The portion occupied by the spinal cord is
absolutely larger than in the mastodon, and it is but slightly defined, from the
portion for the pivot of the axis, by slight tubercular elevations for the trans-
verse ligament. ? ;

The atlas is proportionately longer than in the mastodon, but is of less
width. The inferior arch beneath is nearly flat, and without a hypapophysis,
and on each side presents a superficial, rough prominence for muscular
attachment. * The neural arch is comparatively long and narrow, and appears
to be devoid of a protuberance. .

The articular concavities for the occipital condyles are deeper and more
strongly sloping than in the mastodon. They are separated below by a deep

‘notch at the fore part of the inferior arch. Above, they are removed from
cacki other double the distance.

The articular facets for the axis are ovoidal, slightly concave, and incline
at-an angle of nearly 45°. They are separated below for a couple of
inches by the thick back border of the inferior arch of the atlas. Above,
they are separated by the long semicircular edge of the neural arch. _

The inferior arch of the atlas supports a facet for the odontoid process of
the axis, which is distinct from the articular facets on each side of the latter.

The transverse processes are unlike those of the elephant and: mastodon,
and are more like those in ordinary ruminants, &c. The ends are broken
off, but they appear as broad, thick plates, extending fore and aft , ‘though not
the entire length in either direction.

The canal for the vertebral artery perforates the transverse process fore
and aft from the back half of the upper to the anterior part of the lower sur-
face. As a groove, it-then turns upward in advance of the root of the trans-
verse process, and is directed inward to a canal perforating the neural arch

anteriorly above the position of the articular concavities for the occipital

condyles.
Approximative measurements of the atlas are as follows

Inches.
Breadth between the outer edges of the anterior articular concavities............ 63
Depth of the atlas posteriorly from above downward .........---.--...--------- 43
Breadth between the outer edges of the posterior articular facets ........-..-.-- 64
Fore and aft extent of the inferior arch at the middle....-...-..-.-- sag ¢ Cee 2
luenethot chertlas lateralllye sc. eres = eee eso «R= = Pee FS A 5
Diameter of spinal foramen from above ion terrae owas O28 Ve eee 33
Diameteriofispimaltoramen transversely, <hr eros cr 29-027 - eee ee eee ss OR

Breadth fore and aft of transverse processes .-..-. .---.---..---- . Be AA ah - Oe

103

The humerus of Uintatherium, of which the anterior view of a specimen
is given in Fig. 3, Plate X XVI, is very unlike that of any other familiar
animal. In its peculiarity of form it presents no very evident relationship
with that of the larger pachyderms, odd or even toed, the proboscideans, or
the ruminants. It.is shorter, in proportion with its breadth, than in the
elephant. The shaft is narrowest and most nearly cylindroid at the union of
the upper two-thirds with the lower third. The upper part is prominently pro-
duced outwardly to support a long triangular deltoid tract, the point of which
reaches below the middle of the bone. The deltoid surface looks outwardly
and backward, and is nearly flat, except below where it is depressed. The
back of the shaft presents a broad, nearly flat surface, dividing near the mid-
dle in two portions, of which one extends nearly straight downward, while
the other portion winds outward and forward below the deltoid tract to the.
front of the distal extremity.

The surface of the shaft internally to the deltoid tract is wide and sloping
inwardly. It is slightly depressed on the deltoid expansion, but elsewhere is
nearly flat transversely, and it narrows downward in its extension to the in-
ternal epicondyle.-

- The outer or greater tuberosity of the humerus and the contiguous portions
of the head and deltoid tract are destroyed in the specimen. The inner side
of the head of the bone presents a broad depressed tract rising on the shaft
below in a triangular protuberance, which answers to the ordinary internal
tuberosity of the humerus. From the apex of the angular protuberance, a
ridge descends the shaft defining the inner or anterior aspect-of the bone
from the posterior.

The head is most convex from before backward, and in this direction it
looks as if, in the complete condition, it had not been greater than the trans-
verse diameter.

The external epicondyle is thick and prominent, but is of comparatively
little vertical extent. Its summit forms a thick, rough eminence, extending
an inch externally to the capitulum and several inches in width above it. Its
outer face presents a broad crescentoid surface directed obliquely outward
and downward. It is rough and pierced with vascular foramina, and is
divided into several facets for the attachment of the extensors of the fore-
arm and the external lateral ligament.

The internal epicondyle is a comparatively low, thick, and rough promt-

104

nence, defined from the trochlea by a wide, pitted groove. Its upper part is
destroyed in the specimen. Its back part barely projects posterior to the
position of the trochlea.

Above the distal articulation, where the bone is expanded to form the outer
epicondyle, it is depressed into a broad and unusually deep concave fossa.

The olecranon fossa is broad and moderately deep, but is not much ex-
tended by the protrusion backward of the epicondyles.

The distal articulation of the humerus presents a well-rounded capitulum
on the outer condyle and a broad trochlea extending from it on the inner
condyle. The capitulum is convex and narrows behind on a ridge separating
the posterior prominence of the outer epicondyle from the trochlea. The
trochlear groove is directed obliquely from the fossa in front of the outer epi-
condyle downward and inward, then backward, upward, and outward to the
olecranon fossa.

The measurements of the bone are as follows:

Inches.
Length of the humerus internally ..-......-....- Jebee do catia =e oo 204
Width transversely of the heads 7-2-3202 et oe ete 43
Width of shaft at the middle from the lower part of the deltoid tract to the pos-
terommbernall bonder sc). jews. sii. sees ee see a as sees on ee 44
Phickness of shaft at middle of Same position .:.---.-2:-.-..-- .9. 2-40-52 =e=eeee 24
Circumference of narrowest part of shaft... -.2.-..22: 0). 22.22. = 2 See ee eee 93
Diameter transversely of narrowest part of shaft ................-.------- ©. pul weep
Diameter antero-posteriorly of narrowest part of shaft ...........-...----- nose
Breadthyaity the epicondyWlesy =e ors aera erate eee Soa bo 2 ~ he
Breadth of/distal articulation... 2. 92277825. ee ee 54

The mutilated upper extremity of the femur, represented in Fig. 4, Plate
XXVI, was found by Dr. Corson, on the buttes west of Dry Creek Canon,
a dozen miles from the former specimens. It is suspected to pertain to Uin-
tatherium, though it would appear to have belonged to a larger animal, and
perhaps a different species, than the one to which the cranium and humerus
are referred. The specimen has about the same size and form as the corre-
sponding part in the elephant, but the great trochanter is destroyed. ‘The
length of the fragment is about 11 inches. he head is 5 inches in diameter,
but its surface is too much mutilated in the specimen to determine whether
it possessed a pit for the attachment of a round ligament, or whether it is
absent as in recent proboscideans. The outer border of the shaft below the
position of the great trochanter is 23 ches thick. From the appearance of

105

the specimen, the femur in its entire condition has evidently resembled that
of the elephant more than it does that of the perissodactyles.

The mutilated distal end of a femur, represented in Fig. 5, is also supposed
to belong to Uintatherium, though it did not pertain to the same individual as
the preceding specimen. It was found in the same locality, but at a distance
from the former, and was derived from a different stratum, as it has an adher-
ent friable sandstone matrix, while the other has an adherent indurated clay .
matrix. It is considerably smaller than the corresponding part of the femur
of the elephant, and is very different in anatomical character. It is propor-
tionately less thick. The shaft above the articulation, on the front and at the
sides, presents -a continuous transverse convexity, without any depression
whatever above the position of the trochlea. The posterior surface in the
same direction, between the position of the low epicondyles, is concave.

The loss of part of the outer condyle prevents a comparison of breadth
with the inner one, but this is more prominent posteriorly than the former.
The trochlea is shallow and: but feebly prominent anteriorly in comparison
with that in the elephant. Its articular surface is continuous with that of
the inner condyle, and also that of the outer one, so far as it is preserved in
the specimen, without the slightest definition. The: intercondyloid notch
commences at the bottom of the trochlea and gradually widens backward and
upward with a curve outward.

The length of the fragment of the femur is 6$ inches. The breadth be-
tween the epicondyles is about 54 inches; the thickness of the inner condyle
and trochlea together is 5 inches, and the depth of the trochlea along its
groove is 24 inches.

Several large tarsal bones, found together on the buttes to the west side of
Dry Creek Caton, may perhaps belong to Uintatheyium. They consist of a
calcaneum, astragalus, and cuboid bone of the left foot, and fit well enough to--
gether to have belonged to the same individual. In form and proportions,
though somewhat peculiar, they more nearly resemble those of the mastodon
and elephant than of other known animals.

The caleaneum, of which an upper view, half-size, is given in Fig. 6,
Plate XXVI, is remarkable for its short robust character. The tuber calcis,
in comparison with that in the ordinary proboscidians, is very short. The
breadth of the tuber exceeds its length, and the depth exceeds the breadth.
The thickened extremity narrows below and is continuous with the thick

longitudinal: plantar ridge. The upper part of the tuber inclines nearly
14 ¢

106

straight backward from the articulation. Its outer surface forms part of an
irregular plane with the fore part of the bone.

The sustentaculum is thick and three-fourths the length of the bone. The
groove beneath for the flexor-tendons is well marked. The articular surface
it supports for the astragalus, is larger than that on the body of the bone.
The groove separating the articular surfaces for the astragalus nearly occu-
pies the middle of the bone. Both surfaces are flat in front, but convex back-—
ward behind.

No articular surface exists for the fibula) At the fore part.of the bone
there is a small articular facet for the cuboid. The remaining portion of the
front surface forms a deep and wide irregular plane.

The astragalus, of which upper and lower views are given half-size in
Figs. 7, 8, Plate XX VI, resembles that of the ordinary proboscideans. ~The
bone is irregularly square, with nearly equal horizontal diameters, and of less
thickness than these. :

The upper articular face has nearly the shape of that in a mastodon, but
is rather more depressed posteriorly. The fibular extension holds about the
same. proportion to the tibial surface as in the animal named.

The calcanean articular surfaces are the reverse in their comparative size
to what they are in the mastodon, the inner one being the larger. Both are
also more concave fore and aft than.in that animal.

The navicular articular surface is proportionately deeper in comparison with
its width than in mastodon, and is well defined outwardly from the cuboid
articular facet.

The cuboid is triangular in outline, with rounded angles, and with the
thickness more than half the breadth or depth. Proximally it presents a
double articular facet, of -which the division for the astragalus is larger than
that for the caleaneum. The former division is continuous with a narrow
facet on the inner side for the navicular. Distally the bone also presents a
double articular facet, the divisions forming an obtuse angle.

The measurements of the tarsal bones are as follows:

Calcaneum.
: Lines
enethrotscaleanewm .< <.2; 5022 - et) eaneaaes heteet- ciao ot =i ut oe 42
Breadthvat fore part... 2.0.53 Steet pee ee ee ol ae 2 6 oh ate en 39
Depshvattorepart extermally.. (2-022) eee eee et ee le 31
Length of tuber calcis from the outer articular facet above........-..---------- 20

Breadth transversely of the outer articular facet for the astragalus. .-.-. Pees Ales,

107

° >, Lines.
Breadth fore and aft of the outer articular facet for the astragalus ....-..---..- 23
Breadth transversely of the inner articular facet for the astragalus...- - Rett et 18
sreadth fore and aft of the inner articular facet for the astragalus. ............ 24
Breadth transversely of the articular facet for the cuboid.................- a ent
Breadth vertically of the articular facet for the cuboid ...... . 1 ga ea a ae 10

Astragalus.

F Lines.
Greatest breadth fore and aft of the astragalus at inner side.......--....-.--.-. 50
Greatest breadth transversely of the astragalus.........-..----.--------- Beye Oe
CLeAVeSMMCKNCSSOL AStIAPAlUS 22 222 scc + ea sent cet e epee cee nee vee Fae Oe
Breadth of tibial articular surface at middle transversely.......-..-..----.--.- 38
Breadth of tibial articular surface at middle fore and aft ...-... Ws PE ie ee hig ays 32
Breadth of articular facet for scaphoid..-.-... .......-. fos Oe ee 40
iepuimonanvicnlar facet tor scaphoid.-.....-.,.......---0.-.2eee cece cee e- 28

Cuboid.

Lines.
rem CHC CIN a WOR 6 ee. . myles 2 elected Scab ae Se yoo e Sa Shee tye ons 25
Eemmeivottie CUDOI INfeIOTIY =~. ..2,°--. <2 2% -<<0 1.0 anes ses-ss--< ace i 25
Mem eOMmumercIboldaat Centers. 02.22 2.2 .s ees ses veces ne See cel eel tence nce 15

The canine tooth, originally described and referred to a carnivore with the
name of Uintamastiz atroz, is represented in Figs. 1 to 3, Plate XXV. The
specimen is broken into two pieces, is mutilated at the point, and has lost
“apparently several inches of the base. In its perfect state the tooth approxi-
mated a foot in length, of which it now retains about three-fourths. It is saber-
like in. general form—long, laterally compressed cylindroid, and moderately °
curved. It appears more curved at the base, and from this position, also, has a
somewhat outward deflexion, so that the tooth in its course curved forward and
downward with an outward divergence. Laterally from the base it gradually
tapers to the point; fore and aft it gradually narrows to near the lower third,
when it becomes slightly expanded before tapering, so as to assume the shape
of a lance-head. This likeness is rendered more striking internally by the sur-
face being concavely impressed in front and behind the axis extending toward
the trenchant borders of the lance-head extremity. Externally, it is impressed
in like manner to a less extent posteriorly, but not anteriorly. Above the
lance-head extremity of the tooth it is obtusely rounded in front and behind,
and in this position is elliptical in transverse section, as represented by the
outline, Fig. 5. A section near the middle of the lance-head extremity has
the form represented in Fig. 4.

The tooth, so far as the specimef extends, appears to have been invested

with thin enamel throughout. Externally, it reaches to the broken edge of

108

the base, and, internally, appears to have been lost from the corresponding
position by erosion. Externally, it is longitudinally rugose, and the rugosity
appears to be greater toward the point, and, to some extent, is divergent
toward the trenchant borders. Internally, the rugosity of the enamel is less
marked, and toward the point it is worn off for several inches along the axis
and near the borders from the attrition of an opposing lower tooth. The ex-
tent of attrition would apparently indicate large lower canines. ,

At the broken base of the specimen the borders of the exposed pulp cavity
are nearly 4 lines thick. The fore and aft diameter of the tooth 2 inches
below the broken base is a little under 2 inches; the thickness is 13 lines.
The breadth of the tooth. just before expanding in the lance-head extremity
is 1$ inches. The widest part of the latter appears to have been a couple of
lines greater.

The tusk above described, though apparently according in form with those
of Dinoceras nurabilis, as described by Professor Marsh, exhibits different
proportions, having less breadth and greater thickness. Thus Professor
Marsh gives as the diameters of the tusks of D. mirabilis 64 millimeters
breadth, and 25 millimeters thickness. The tusk above described has a
breadth of 50 millimeters, and a thickness of 28 millimeters. ..

From the description of the skull of Dinoceras given by Professor Marsh,
as before intimated, I have been led to view the large tusks above described,
and originally referred to a carnivore with the name of Uintamastix, as really
pertaining to Uintatherium, and perhaps to the same species as that indicated
by the cranial specimen referred to U. robustum.

The molar tooth of Uintatherium, represented in Figs. 13, 14, found with
the large tusk, has the same form and constitution as the upper molars first .
referred to the genus, except that it is considerably smaller, and has no
tubercle behind the summit of the conjunction of the lobes of the crown.
Proportionately, also, the basal ridge is much better developed at the inner
part of the crown, where it is continuous with the stronger ridge in front and
behind. The antero-posterior diameter of this tooth is 114 lines, and its
transverse diameter is estimated at 134 lines.

The tooth I supposed to be an upper premolar of U. robustum ; if, how-
ever, it is a true molar, its comparatively small size, and the absence of the
characteristic tubercle on the posterior slope of the conjunction of the lobes
of the crown, as existing in the species just named, would indicate that it

109

probably belonged to a different one. Found in association with the canines’

referred to Uintamastix atrox, it may pertain to the same animal.
Order Rodentia.

Small quadrupeds with clawed toes. Teeth consisting of two long curved
incisors in each jaw; no canines, and the molars separated from the former

by a wide interval.
PARAMYS.

An interesting peculiar extinct genus of gnawers of the sciurine family is
indicated by a number of specimens, consisting of fragments of lower jaws
with teeth, which were discovered by Dr. Carter, in the summer of 1871], in
the Tertiary formation in the vicinity of Fort Bridger.

As in the squirrels and marmots, the lower molars are four in number,
and are inserted each by two fangs. They are nearly of the same size, but
are proportionately narrower than in the animals just mentioned, as the fore
and aft diameter exceeds the transverse, while in most sciurine animals the
reverse condition usually exists.

The crowns are short, square, tuberculate, and enameled. The arrange-
ments and proportionate size of the tubercles at the four corners of the crown,
including a concave surface, are the same as in the squirrels.

The lower jaw is proportionately shorter and deeper than in most known
rodents, the reduction in length being mainly due to a less development of
that part of the bone in advance of the molars. 'T’o compensate for the dif-
ference in length and to make room to accommodate the incisors, these teeth
reach farther back than usual. In squirrels and marmots their posterior
extremity reaches a short distance behind and beneath the last molar. In
Paramys it reached further backward, upward, and externally to a level
with the crown of the last molar.

The jaw in advance of the molars is not only short compared with the usual
condition in most known rodents, but the acute edge of the hiatus between
the molars and incisors is almost on a level with the alveoli of the teeth,
instead of forming a deep concave notch, so conspicuous a feature in the lower
jaw of the gnawers generally.

In sciurine and most other rodents the ridge defining the masseteric fossa
extends far forward on the side of the jaw to a position beneath the second or

110

even the first molar tooth. In the rabbits the defining ridge is comparatively
‘far back, extending only to the position of the interval of the last two molars.
In Paramys it holds an intermediate position, extending as far forward as the
position of the third molar, where it forms a conspicuous angular prominence,
as in the marmots.

The mental foramen, much higher in relative position than usual in rodents,
is situated in advance of the molars a short distance below the edge of the
hiatus separating the latter from the incisor.

PARAMYS DELICATUS.

The largest species of Paramys was, perhaps, about a fourth less in size
than the Maryland marmot, though its series of molar teeth is nearly equal
in size, measuring three-fourths of an inch in length. It is represented by
two specimens sent to me by Dr. Carter, consisting of portions of the right
and left sides ofthe lower jaw, containing most of the molars and portions of
the incisors. One of them is represented in Fig. 23, Plate VI, of the natural
size. The triturating surfaces of the molars of both specimens, magnified
three diameters, are represented in Figs. 24, 25.

In one of the specimens, Fig. 23, two mental foramina exist, one in the
position, previously indicated, in advance of the molars, a short distance
below the edge of the jaw; the other is situated lower down below the posi-
tion of the first molar. In the other specimen the foramen exists in the lat-
ter position, and as the jaw is broken in advance, it cannot be determined
whether a second existed, which is, however, probable, as it is the usual and
normal position of one. A prominent tubercle is formed at the angle of con-
vergence of the ridges which define the masseteric fossa.

PARAMYS DELICATIOR.

A second species is indicated by a specimen consisting of the greater por-
tion of the left ramus of a lower jaw, represented in Fig. 26, Plate VI. It
retains the second molar tooth, the triturating surface of which, magnified
three diameters, is represented in. Fig. 27 of the same plate. The molar
series has measured about 74 lines in length, and the animal was about the
size of our common gray rabbit. . . ee.

Since writing the above, I have received from Dr. Carter several additional
specimens which I suspect belong to the same species. One of them, an in-
termediate lower molar, is represented in Fig. 16, Plate XXVIII. It suffi-

111 :

ciently resembles the tooth of Fig. 27, Plate VI, originally referred to P.
delicatior, to pertain to the same species, though it is slightly larger.
The other specimen, apparently from the same individual, consists of a pair
of upper molars represented in Figs. 17, 18, Plate XX VII, magnified three
diameters. - They have nearly the form and construction of those of the

Sciurides.

The fore and aft diameter of the lower molar is 1.8 lines.. The fore and
aft diameter of the upper molars is 1.8 lines, and the transverse diameter is
2 lines. ; |

PARAMYS DELICATISSIMUS.

A third and still smaller species of Paramys is indicated by a specimen
consisting of the greater portion of the right ramus of a lower jaw contain-
ing all the molars, and a second specimen consisting of a small fragment of
another lower jaw containing the second molar. The first specimen of the
natural size is represented in Fig. 28, Plate VI. A view of the triturating
surfaces of the molars, magnified three diameters, is given in Fig. 29. The
_ molar series measures } an inch in length, and the animal was about the size
of the common gray squirrel.

Comparative measurements are as follows:

P. delica- | P. delica-| P. delica-
tus. tior. tissimus.
: Lines. Lines. Lines.
Length of lower molar series....-..-.- --.-..---.-.-- oe 9 74 6
Length of hiatus in advance of lower molar series. .... - - -- SH, fe Soaidees 3
Depth of jaw below the second molar..........--- pS sp 6 5 L
Fore and aft diameter of incisor ....-.. -- AE RRS AAC ee 24 2 14
Mramsverse diameter OfANCISOL ...-.---2-+-.---4.+20-5--- 13 13 1
Fore and aft diameter of second molar.............----.- 22 8 15
Transverse diameter of second molar.......--.--..------ ; 14 13 12

MYSOPS.
Mysors MINIMUS.

A small rodent, intermediate in size to the common mouse and the brown
rat, is indicated by a specimen discovered by Dr. Carter at Grizzly Buttes
and sent to the author last summer. The specimen consists of the median

portion of the right ramus of a lower jaw containing the last two molars, the

112

fangs of the others, and part of the incisor. It is represented in Fig. 31,
Plate VI, magnified two diameters.

The jaw in its form, proportions, and construction, and the number of teeth
and their relative position, agree with the conditions in Paramys, but the form
of the molars is sufficiently different to refer the specimen to a different genus,
for which the above name has been proposed.

The molar teeth, as in Paramys, are four in number, inserted each by
a pair of fangs. The crowns are quadrate and invested with enamel.
The triturating surface, instead of being constructed like that of the squir-
rels, is more like that of the rats, as seen in Fig. 32, Plate VI, in which
the last two molars of the specimen are represented magnified eight diam-
eters. The crown of the third molar exhibits two transverse lobes, or
ridges, joined by an intermediate narrow ridge, and the inner extremities of
the lobes include a trilateral tubercle. ‘The enamel being worn away from
the prominences of the crown leave exposed a pair of transversely ellipsoidal
dentinal surfaces joined by a narrow isthmus. Upon the summit of the inter-
nal tubercle a small islet of dentine also appears.

The last molar exhibits three transverse ridges or lobes, of which the
anterior is the thickest, the middle one the thinnest, and the posterior the
shortest. The anterior lobe is worn so as to exhibit a transversely elliptical
surface of dentine bordered with enamel. The middle ridge of the crown —
appears sigmoid and is unworn. The posterior lobe presents an exposed islet
of dentine on the inner half of its length. ms

The anterior molar of Mysops, like the last one, is more elongate fore and
aft than the two succeeding ‘molars, but it is proportionately of less size than
in the rats, and has not three fangs as ih these animals.

The length of the molar series is } of an inch. The first and fourth
molars are about + of a line fore and aft; the intermediate ones about ?. The
incisor measures about 4 of a line fore and aft by 2 transversely. The depth
of the lower jaw below the second molar is 2? lines. The length of the

hiatus in advance of the molars is 14 lines.

Mysors FRATERNUS.

Since writing the foregoing I have received another specimen, which may
belong to Mysops. It was found by a Shoshone Indian, and given to Dr.
Carter. It consists of a portion of the right ramus of the lower jaw, repre-

113

sented in Fig. 14, Plate XX VII. It contains the last three molars, the tritu-
rating surfaces of which are represented in Fig. 15, magnified eight diameters.

The jaw is proportionately deep and short, compared with that of the rat.
The masseteric fossa is deep, and defined by a rectangle, the apex of which
reaches as far forward as the position of the third molar tooth. The border
of the jaw at the hiatus in advance of the molars extends nearly on a level
from their alveoli to that of the incisor.

The molar teeth, though having the same general constitution as the cor-
responding ones in the jaw-fragment of Mysops minimus, above described,
appear sufficiently distinct to pertain to another species, and I have therefore
distinguished it as such with the name of M. fraternus. —

In the jaw-specimens of both species the molars are worn nearly to the
same extent. In comparing the corresponding teeth, it will be seen that the

_ third molar in AZ. fraternus has.a greater breadth fore and aft, and the last
molar is of more uniform width transversely. In both teeth the intermediate
* . conical lobe, occupying the inner part of the crown, is proportionately more
robust in MZ. fraternus. ;
The depth of the jaw below the third molar is 2.6 lines; the breadth of
each of the three back molars fore and aft is about eight-tenths of a line; the
space occupied by the four molars is a little over 3 lines.

SCIURAVUS.

In the American Journal of Science for July, 1871, Professor Marsh has
described an extinct genus of rodents from remains found at Grizzly Buttes,
‘under the above name, and refers them to two species with the names of
Sciuravus nitidus and S. undans. The former, described from an upper-jaw
fragment with three molars, was about the size of the brown rat. The latter,
indicated by a lower-jaw fragment with the incisors and the anterior three
molars, was a somewhat larger animal.

While we bave not the means of determining whether Paramys is abso-
lutely distinct from Sciuravus, we have the opportunity of examining a speci-
men belonging to a different genus from the former, and which we suspect
pertains to the latter. The specimen in question consists of a fragment of the
left side of the lower jaw, containing the third molar, the alveolus behind, and
part of that in front. It belonged to an animal but little larger than the rat.
The fossil was found at Grizzly Buttes by Dr. Carter. The only remaining

15 G

114

tooth it contains is represented in Fig. 30, Plate VI, magnified eight diam-
eters.

The tooth is about a line in breadth, and, together with the alveolus back
of it, occupies a space of 24 lines. The crown of the tooth is quadrate,
broader than wide, and is composed of four principal conical lobes, as in the
syuirrels, and as in its associate Paramys The sculpture and connection of
the lobes is different, as may be conveniently observed by comparing Fig. 30
with Fig. 27, representing a tooth of the same side of Paramys. It is espe-
cially to be noticed that in the latter the back pair of lobes include, between
them and the anterior lobes, a broad hollow, and the former are connected
behind by an acute ridge, which forms the posterior border of the crown.
The broad hollow of the latter is closed externally by a festoon-like ridge
connecting the outer lobes at their base.

In the supposed tooth of Sciuravus (Fig. 30) the broad hollow of the crown
so conspicuous in Paramys and Sciurus is not evident. The posterior lobes
are conjoined by a transverse ridge, and are bounded behind by a thick ridge
descending inwardly from the postero-external lobe. The transverse valley
of the crown is occupied by a pair of ridges diverging from the postero-
external lobe to those in advance.

Order Carnivora.
PATRIOFELIS.
PATRIOFELIS ULTA.

A carnivorous animal, rather larger than our common American panther, ©
and about the size of the jaguar, to which the above name has been given, is
indicated by remains in the Bridger Tertiary formation. The specimens
from which it was originally described in the Proceedings of the Academy
of Natural Sciences for March, 1870, were obtained near Fort Bridger, .
Wyoming, during Professor Hayden’s exploration of 1869. They consist of
portions of both rami of a lower jaw, unfortunately with most of the teeth
lost or mutilated. The right ramus is represented, one-half the natural size,
im Hig. 10, Plate If.

The jaw of Patriofelis contains a series of five molar teeth immediately
succeeding the canine tooth without conspicuous interval, as in some of the
viverrine and musteline animals. The molar teeth are all inserted by a pair

of fangs, and none of them appear to be of the purely tubercular kind. The

115

first of the series is smallest, and the third the largest; the fourth was inter-
mediate in size to the latter and the last one, which little exceeded the
second.

The crown of the last molar in the specimen appears as if it had been
composed of an anterior pointed, or perhaps trenchant, lobe, and a large pos-
terior heel.

The crown of the penultimate molar appears to have been nearly of the
same character. In the crown of the antepenultimate molar the posterior
heel forms a median acute ridge from which the sides slope toward the
bottom. The outer slope, nearly twice the depth of the inner, is bounded
behind by a ridge descending from the summit of the heel. The inner slope
is bordered by a basal ridge curving downward and forward from the summit.

The canines, as indicated by portions of the alveoli, are large and powerful

_ teeth, as in feline animals. The alveoli are about $ inch in diameter.
‘The jaw has nearly the same form as in the panther, but is proportionately
~ shorter, and beneath the molar teeth of greater depth, in this respect resem-
bling more the condition in the striped hyena. 'The condyle has the same
form and relative position as in ordinary carnivora, but is thicker or of greater
extent on its articular surface fore and aft than in the panther. Its compara-
tive breadth is undeterminate, from its being broken at both ends in the
specimen.

The back portion of the jaw is proportionately narrower than in the
panther; and the coronoid process, which appears to have had the same
‘form as in this, is likewise narrower. ‘The masseteric fossa is not so deep as
in ordinary carnivora. [Extending from the coronoid downward, a little
below the level of the condyle, it becomes, rather abruptly shallower, and
from this position gradually lessens in depth toward the base, from which. it
is not abruptly defined by a narrow ridge, as in the ordinary carnivora.

The symphysis is strong, and the rami approaching it thick, as in the
panther. A group of seven mental foramina occupy a position at the side
of the symphysis. The largest of them, as in the panther, is situated outside
the back part of the canine alveolus. .

From the absence of the characteristic portions of the teeth, the exact
relationship of Patriofelis is not clear. It is perhaps intermediate to the

feline and canine animals.

116

Measurements from the lower jaw of Patriofelis ulta are as follows :
Inches. Lines.

Hstimated len Sch Ol Yaw isn van tee le ee ee ee ee 0
Distance from back of condyle to canine alveolus ............ .........-- 5 4
Distance from back of condyle to back of last molar............ ......... 2 3
Space.accupied. by the molar Sexies:: \.- <-.-leecui<>'= oem ee ee nie oie 3 0
Breadth of coronoid at base: s..0 22.055) nee oss oe eee ee yey ad a
Depth of jaw below penultimate molar... .< -. -.630d-c 5b. 2-be -sep eres 1 4
Depth of jaw below;back of last.molar..:-=2,..:% .<2.< =. bute oon Soe ee 1- 6

Measurements of the molar teeth, estimated from their fangs and alveoli,

are as follows:

Lines.
Breadth: of tirst'molar tooth: .2..502:..--2 t¢m02.00 cceeees ese. ele 5
Breadth’ of second molar tooth’. .212. 20... 2G... - 52) e22 eee ne eee i
Breadth of third molaritooth....4-~-)9:-4:. <ia42-0<cee 2 S228 2-2 2 <yiee *
BIKE Ore OAD TAOMEHe TOON scaccanse econ sedoy ssuseosenucce 2 oe Tf
Breadth of tifth molar tooth...-. .-..- athalines we ceed bee eee bt, ie Oe 8

Fig. 20, Plate VII, represents a tooth discovered by Dr. Carter near Fort
Bridger. It appears not to belong to the lower jaw of Patriofelis, but per-
haps belongs to the upper jaw. The crown is composed of a large conical
lobe with a broad heel, the sides of which slope from a median ridge. ‘The
breadth of the crown is 84 lines; its thickness 5 lines.

‘SINOPA.
SINOPA RAPAX.

A lower-jaw fragment, containing two teeth and portions of two others,
represented in Fig. 44, Plate VI, appears to indicate an extinct genus related
to the canine family. ‘The specimen was discovered by Dr. Carter in the
vicinity of Fort Bridger, and was by him presented to the writer. It belonged
to an animal about the size of the gray fox.

The specimen is insufficient to ascertain with any certainty the exact rela-
tionship of the animal to which it belonged, but the character of the teeth
leads me to view it as having held an intermediate position to the existing
genus Canis and the extinct one Hyzenodon.

The teeth preserved entire in the specimen appear to correspond with the
last premolar and the first or sectorial molar of, the fox, and the remains of
two teeth behind would be of the second and third molars. The last pre-
molar is larger than the molars. Its crown is as wide, but is longer than that
of the tooth retained behind it. The form of the crown is more like that in

BL

Hyzenodon than in the fox. It is -proportionately longer and narrower than
in the latter, and the accessory cusp at the back border of the principal one
in the fox is nearly obsolete in the fossil. The heel of the crown is better
developed than in the fox. It forms a median acute ridge, and slopes off on
each side to the rounded base of the crown. ae

The first molar, as hefore intimated, is smaller than the last premolar. It
is as wide as the second molar, but not so thick, and is slightly wider than
the last molar. It is proportionately better developed in its relation with the
succeeding molars than in Hyznodon. Its crown is intermediate in form
and in the development of its parts to that in the fox on the one hand and the
raccoon and badger on the other. The fore part of the crown, consisting of
rather more than one-half, corresponds with the sectorial portion of the same
tooth in the fox, but accords more in shape and the relative position and de-
. velopment of its points with the homologous portion in the raccoon and bad-
ger. ‘The heel of the crown is bordered by a horseshoe-shaped ridge inclos-
ing a cup-like concavity.

The heel of the second molar, the only portion of the crown retained in
the specimen, is stouter than in the first molar, but has the same shape. The
width of the crown is about equal to that of the tooth in advance, but has
been slightly thicker.

The last molar is a two-fanged tooth like those in advance, but is not quite
so wide, and a small portion of the back of the crown indicates it to have
been of less thickness.

The base of the jaw-fragment is broken away in the specimen. The por-
tion preserved presents nothing peculiar.

Measurements of the fossil are as follows:

Lines
Space occupied by the last premolar and molars.........-......-....2-.-.---- 15
Space occupied by the molars....-. ..-.-.. Rae is see emcee eis eats ons 11
reauiuon Crown OF laSi premolar. 02-6225 net ee ee ee 4
ieneihvot erown Of last premolar at middle ..-.....-.--.2-. 22.2 see eee e ee eee 34
Jip SAGE, ie CMON NONE ERS Ag (110) 2) Se a ee
eneihvor crown of first molar af principal cusp ...-...-...:.--........--- -- 23
Thickness of crown of first molar at heel ...-......-----.---..-...205 224. --2-- 2
IsreadinvOt CLOwMIOl SCCONG MOAT... <2 2. ous ion) nie ee se be nee see wee ee ne 4
Thickness of crown of second molar at heel.......--...----------.- TERT 24
Pere tUUMCOMeLONMOR MAST WOlAle scm... ose een ese Seen aden Gene gk eon sben ees 3s

The name Sinopa, applied to the extinct genus, according to Professor
Hayden, is aboriginal, and is applied by the Blackfeet Indians to a small fox

118

While the original notice of Sinopa rapax was in print, in the Proceedings
of the Academy of Natural Sciences of Philadelphia, Professor Marsh pub-
lished a description, in the American Journal of Science for 1871, of some
remains of a carnivore from the vicinity of Fort Bridger, under the name of
Vulpavus palustris. It is characterized from several upper molars which accord
in size sutliciently to pertain to the same animal as that aboye described.
Further researches may prove the two animals to be the same. t

SINOPA EXIMIA.

A jaw-fragment, discovered by Dr. Carter at Grizzly Buttes, and repre-
sented in Fig. 45, Plate VI, belongs to a smaller carnivore than the preced-
ing. It was probably allied to the former, and may perhaps pertain to a
smaller species of the same genus, of which I have some doubt, though, in
the absence of more confirmatory evidence, I have considered it as such.

The specimen contains two teeth, which sufficiently resemble those re-
tained in the jaw-fragment referred to Sinzopa rapaz, as to render it probable
they are the corresponding ones, though the contiguity of the symphysis leads
me to suspect that they may be the last two premolars. As seen in the
figure, the back of the symphysis is just below the position im advance of
the first tooth of the specimen. The teeth in shape are nearly like those in
Sinopa rapax, but the proportions are reversed. The crowns of the two
teeth have the same length, but the hinder one is wider and thicker.

The measurements of the specimen are as follows:

Lines.
Depth of the jaw below the teeth.....-----..-.-- BN Oe RRS oes et a < 43
Space occupied by the two teethy.- =~ 72-2522 snes =) eines ae 44
Width of the crown of the first tooth .-...) 222. 02-5. 4.22 =- e523 2
Length of the crown of the first tooth..........--------- Peer. 24
Widthor the crown of the second tooth: <2. ei. = 2 oe eee Ue eee 24
Length of the crown of the second tooth’ ~ 7272. fy 222 sees ne 24

UINTACYON.
UINTACYON EDAX.

An interesting fossil, recently received from Dr. Carter and discovered by
him in the Bridger beds, consists of the greater portion of the right ramus of
a lower jaw, represented in Fig. 6, Plate XXVII. The specimen indicates
a carnivorous animal, probably marsupial, and of a hitherto unknown genus,
for which the above name has been proposed.

119

The jaw contained a series of eight molar teeth and a canine separated
from the former by a small hiatus. * Of the molar teeth, the specimen retains
part of the first molar and the succeeding molar, represented in Figs. 7, 8,
and the intermediate three premolars represented in Figs. 9, 10.

The jaw-fragment agrees in its form and proportions with the correspond-
ing part in the existing fox. The teeth also, so far as they are preserved, are
nearly like those of the latter animal.

The canine tooth was equally well developed as in the latter, and the first -
premolar is inserted by a single fang. The second premolar likewise resem-
bles the corresponding tooth of the fox. |

The third premolar is peculiar, and perhaps anomalous. It resembles more
the form of an upper premolar than the usual form of lower premolars. It
has three fangs, of which two are inserted in a line with those of the con-
tiguous teeth, while the third fang is external. The crown is a four-sided
pyramid with projecting basal angles, of which the postero-internal one is the

‘most prominent.

The fourth premolar is like the last one of the fox, but is proportionately
thicker. The fifth premolar is lost, and, like the preceding tooth, was inserted
by a pair of fangs.

The first molar has lost the fore part of its crown, and this appears not to
have been proportionately so well developed as in the fox. The crown of
the second molar is nearly of the same form as in the latter.

The last molar is a small tooth, as in the fox, and is also inserted by a single

fang.
The measurements of the specimen are as follows:

Lines.
Wepih of lower jaw at second premolar. ...........-.-2-..- .--.0.2.--+----- 4.8
Wepreoh lower jaw at rst molar... 2... - 2. oe ek ene eee te eee 4.8
Distance from fore part of canine to back of last molar.......... .....--. ete wise)
Menonheonr tie Molar SErieS 2. . 2... donee) ee ee ee eee ee ees ge ee 14.8
Length of the premolar series ....... ..-..- ERENT oe Snes are sept tee ees Palate 8.8
Memon Mom EMeNUEMe; MmOlaE SCLICS. <<... 20s. see tec. ee ee eee e eg we eee eee 6.0
Breadth of second premolar. .- . - ni ee NS a Oe et REE reer CE We eee eT
T Pie SAUL N @RE DU GL FORTEC EWU ee rare eae en PE aoe 1.5
EreTCri Om hie tourth premolar... 26.2.2... 5.06 cee ee ee ee eee eee ewe 1.6
eres dahvotthentitul premolar 20... ....-.- 0+. - eee se eee ooo ewe el eee eee a4
Spire aii Oe UM eatin Game ets see eicecia apy csr gon iS a eseeinie ety hee cies Scie ke ne pee 3.2
Ee Ream MeOlese COMM Ole. aoe fee ce ae en cee See ee ce ee mcinn ane we ees 2.0
ee reneOlah mimolMnOlniamenecwe tee J hee 2 8s Ske elon ten so aaah eee de) sb es 1.0

The main peculiarity of the fossil is the presence of an eighth tooth to the

120

molar series. The one in excess of the usual number, without other considera-
tion than convenience, I have viewed asa premolar. From its anomalous, or at
least unusual, form, the fourth of the series of the premolars may be regarded
as the additional tooth. Without it, the jaw would indicate a small canine
animal, or at least a species of a closely allied genus. The animal was about
half the size of the common fox.

UINTACYON VORAX.

Perhaps a larger species of the genus just named is indicated by the jaw-
fragment represented in Fig. 11, Plate XX VII. The specimen was obtained
on Henry’s Fork of Green River, during Professor Hayden’s expedition of
1870. | |

The jaw-fragment agrees in form with the corresponding part of the jaw-
specimen of U. edazx, but from its proportions belonged to an animal twice the
size. It contains the penultimate molar, the heel of the one in advance, and
the alveolus of the last molar. The teeth agree in their proportions with
those of U. edax, and the penultimate molar, represented in Figs. 12, 13,
sufficiently resembles that of the latter to belong to the same genus. The

breadth of the penultimate molar is 2% lines.
Order ilo:

oMoMYs.
Omomys Cae

The first mammalian fossil described from the Bridger Tertiary beds con-
sists of the fragment of a lower jaw with teeth, discovered by Dr. Carter on
Twin Butte, about one mile from Fort Bridger. The specimen is repre-
sented in Figs. 13, 14, Plate XXIX, of “The Extinct Mammalian Fauna
of Dakota and Nebraska,” published as the seventh volume of the Journal of
the Academy of Natural Sciences of Philadelphia for 1869, and is described
on page 408 of that work.

The jaw-specimen was accompanied with fragments of the cranium, for the
most part too much broken to determine anything from them. They would
appear to indicate a skull about the size of that of the common weasel, but:
with weaker jaws.

A fragment of the cranium retains a straight linear sagittal crest about 14

121

lines in length to its bifurcation at the forehead. The temporal surfaces
appear to be full and convex, as in the weasel.

An occipital condyle resembles those of the latter, and measures about 4
lines in its longer diameter.

The ramus of the lower jaw, compared with that of the weasel, is more
slender and delicate in its proportions. In the specimen both extremities
are broken, but a portion of the symphysis is still retained.

The jaw below the molars is of nearly uniform depth, and measures about
2 lines. “The base is slightly convex fore and aft, but makes a concave turn
toward the angle. The masseteric fossa below is well marked. A small
mental foramen occupies a position below the antepenultimate premolar.

In the earlier description of the specimen, I remarked that seven molar
teeth, in an unbroken series, appear to have occupied the side of the jaw. In
the actual condition of the fossil there are four teeth, consisting of the anterior
two molars and the two premolars in advance. In front of these there are
two empty sockets and parts of two others, and behind them there are the
imperfect alveoli for a third molar. The sockets at the front of the jaw I at
first supposed were intended for two additional two-fanged premolars. They
fill up the interval between the retained teeth and the edge of the symphysis
so closely that, from this fact and their relative size, I now suspect that they
may have been occupied by a single-fanged premolar, a small canine, and
two incisors. Assuming that such was the case, without any certainty in the
matter, the number of molar teeth in the series would be six, of which three
were premolars and three true molars. In this view the teeth retained in
the specimen consist of the second and third premolars and the first and sec-
ond molars. Their constitution would appear to indicate an insectivorous
animal which, perhaps, was marsupial in character.

The teeth successively decrease in prominence or height from the second
premolar to the second molar. They resemble in constitution the corre-
sponding teeth of the opossum.

The crown of the premolars is laterally compressed conical, thicker behind
than in front, and is embraced by a basal ridge.. The crown of the second
premolar, more prominent than in any of the other teeth, is triangular, longer
than broad, and sharp-pointed. Its anterior slope is slightly convex and acute;
its posterior slope is longer, slightly concave, and wide. The basal ridge

forms an excavated heel behind, a more elevated ledge in front, and a pair of
164

122

festoons both internally and externally. The inner side of the crown is
defined from the back border by an acute ridge.

The crown of the last) premolar has the same construction as that in advance,
but is shorter and wider. The heel is slightly wider and more excavated, but
the fore part of the basal ridge is not so prominent. The ridge defining the
inner side from the posterior border is slightly more advanced and prominent,
and the surfaces it separates are more concave.

The crowns of the true molars are nearly alike in form and size, though
the first is in a trifling degree more prominent and wider. Théy have the
same general constitution as those of shrews, of the hedgehog, the galeopi-
thecus, and the opossum. Each is composed of two divisions, of which the
posterior is the larger. The anterior division consists of a small, outer demi-
conoidal lobe, with a V-like summit joining byits arms a pair of inner and smaller
pyramidal lobes. The posterior division consists of an outer lobe like that in
advance, but larger, and joining it by one of the arms of its V-like summit,
while the other arm joins a small pyramidal lobe at the inner corner of the
crown. The outer part of the base of the crown is embraced by a basal cin-
gulum nearly half its depth.

The space occupied by the teeth, in the view that there were two incisors,
a canine, and six molars, is 74 lines. The last two premolars and the suc-
ceeding two molars occupy a space of 4.6 lines.

PALAACODON.

PALZACODON VERUS.

Two small fossil specimens, discovered the previous summer by Dr. Carter
at Lodge-Pole Trail, Wyoming, indicate an insectivorous animal, or, perhaps,
a marsupial allied to the opossum. One of the specimens consists of an
upper-jaw fragment containing a molar, which appears to be the penultimate
one of the series; the other is an isolated tooth, perhaps the last upper pre-
molar or first molar.

The jaw-fragment is the portion which forms the anterior abutment of the
zygoma. In advance of the tooth it retains are the remains of the alveoli of
two others, and behind it the remains of another.

The molar of the jaw-fragment is represented in Fig. 46, Plate VI, magni-
fied four diameters. The crown bears some resemblance with that of the
molars of the opossum, but is less narrowed internally, and is therefore more

123

quadrate or less triangular in form. The constitution is similar, but the outer
lobes are proportionately better developed and the median ones are much
reduced in size. A basal ridge nearly embraces the crown, but is nearly
obsolete internally, and is best developed posteriorly, where it forms a wide
festoon. . |

The isoiated tooth is a diminished representative of the one in the jaw-
fragment, and probably held the position of the third in advance of it. It
may, perhaps, represent a smaller specics. ‘The specimens indicate an animal
but little more than half the size of the opossum. How it is related with
Omomys the paucity of material prevents a positive determination. The size
of the teeth indicates a larger animal than Omomys Carteri.

In the American Journal of Science for 1871, Professor Marsh has
described a tooth, from Grizzly Buttes, which he likens to the premolars of
some insectivora, and refers it to a species with the name of Triacodon fallax.

He remarks that the species was probably about two-thirds of the size of
the opossum, which dimensions would be too great for the animal we have
named Paleacodon verus.

The sizes of the teeth referred to the latter are as follows:

: Lines
Space occupied by the penultimate and antepenultimate molars..... ......-.--. 4
Peso PemulbimMmabewmMOlar. . 2 le. soe. Le ew eee eos wc en se cede eee eee 2
Pec DeNUinMALemnOlAr 2.2 25. 5 bale ma sakes ais tS sya atin - Gis ma eleie b Dale es 2:
Eee GME 1G (Sin SURETY CITT Ase 0S nS RUS ka ee ae eee a eee 14

Width of last premolar .... .......... Sete eee eee oe ia eel ta ey 12
WASHAKIUS.

WASHAKIUS INSIGNIS.

A jaw-fragment of a small animal recently sent to me by Dr. Carter is rep-
resented in Fig. 3, Plate XX VII, magnified three diameters. The specimen
was found in the Bridger beds by a Shoshone Indian and given to Dr. Carter.
It is quite different in appearance from any similar fossil from the same for-
mation submitted to my inspection, and appears to indicate a different genus
from those described in the preceding pages. Iam uncertain as to its ordi-
nal affinities, but suspect it to have pertained to an insectivorous animal, per-
haps one of the many which have been indicated by Professor Marsh from fossils
of the Bridger beds.

The jaw-fragment contains the last two molars, the triturating surfaces of

124

which, considerably worn, are represented in Fig. 4, Plate XX VII, magnified
eight diameters.

The portion of jaw is of moderate depth and stout in proportion. The
base is thick and rounded. The masseteric depression is well marked, and is
defined at its lower part in front by a strong ridge descending from the fore
part of the coronoid process and ending in a conspicuous angular tubercle.

The teeth resemble most nearly those of Microsyops. They are inserted
with a pair of fangs; but in the last molar the posterior fang is a connate pair
extended backward.

The crown of the antepenultimate molar is quadrate with rounded corners,
and is composed of four lobes. The postero-external lobe is largest, and is
crescentoid conical. The postero-internal lobe is smallest and conical, and is
joined at the summit by the back arm of the postero-external lobe. The
anterior pair of lobes are connate, and are joined about their middle by the
fore arm of the postero-external lobe. A deep angular valley occupies the
inner part of the crown between the anterior and postero-internal lobes, and
bounded externally by the postero-external lobe. A basal ridge incloses the
outer part of the crown, but is interrupted in the most prominent part of the
postero-external lobe.

The crown of the last molar, at its anterior two divisions, is composed on
the same plan as that of the molar in Bes, but it is ae backward
so as to form an additional lobe.

The measurements of the specimen are as follows:

Lines
Depth of lower jaw, below the last molar... -2-2 0. 50). 09 ee eee eee 2.1
Space occupied by the last two molars............ E alaon Ste es 0 eae 2.4
Breadthiof second molar ..cecson* Secchi e Gee A Pe 2 ee 1,2
Breadth of last molar ...:.255--.2. :- ghey Heatie i Seek 2 vers keane Lh wie 1.4

The genus I have named in commemoration of Washakie, chief of the
Shoshone Indians, with whom I had the pleasure of meeting during my visit
to Fort Bridger. He has always been distinguished for his high re

and for his friendliness to the white race.
ELOTHERIUM.

In the American Journal of Science of 1871 Professor Marsh has described
a molar tooth, from Henry’s Fork of Green River, which he attributes to a
suilline pachyderm with the name of E/otherium lentus. The specimen, he

125

observes, indicates a species about half the size of E. Mortoni, the remains
of which are found in the Miocene Tertiary deposit of the Mauvaises Terres
of White River, Dakota.

Among the collections of fossils from the Bridger beds I have seen no
remains which could be ascertained to belong to this genus. Figs. 28 and
29, Plate VII, represent two views of an incisor tooth which looks as if it
might pertain to HL. Mortont. The specimen was found by Mr. Pierce, of
Denver, twenty miles southeast of Cheyenne City, Wyoming.

REPTILIA.

The Bridger Tertiary formation, in comparison with the earlier Tertiaries
of White River, Dakota, and of the Niobrara River, Nebraska, is remarkable
for the variety as well as the number of its reptilian remains. Amid the
multitude of fossils which have been collected in the latter localities nearly
all belong to mammals; and though the remains of turtles are abundant, they
appear all to be referable at most to a single species for each locality. No
fragment of a crocodilian, lacertian, or serpent has yet been discovered either
in the Mauvaises Terres of White River, Dakota, nor in the sands of the
Niobrara River, Nebraska. From the Bridger beds there have been col-
lected many remains of different species of crocodiles, turtles, lacertians, and
serpents.

Order Crocodilia.

Body lizard-like in form, with four short limbs and feet, and a long,
powerful tail. With long jaws, provided with a single row of teeth inserted
in distinct sockets. Skin protected by bony plates.

CROCODILUS.

The Bridger Tertiary formation contains numerous remains of crocodiles.
Many collected by Professor Hayden’s party in 1870, and others obtained by
Drs. Corson and Carter during the same and the succeeding year, have been
submitted to the inspection of the writer. The specimens were found in
various localities in the vicinity of Fort Bridger, as Little Sandy River, Big
Sandy River, Green River, Black’s Fork of the same, Church Buttes, Grizzly
Buttes, &c. The specimens examined indicate several species, though from
their generally detached and imperfect condition we have not been able to

collocate them so as distinctly and clearly to establish the species. Some of

126

the specimens we have referred to two named species. Professor Marsh
subsequently named. five species from remains obtained in the same locali-
ties during his exploration of 1870. Professor Cope has more recently named
four additional species. It is probable that when the fossils are more care-
fully studied, the number of species to which they have been referred will

- be reduced.

CROCODILUS APTUS.

This species was originally named in 1869 from a fossil preserved in the
Geological Cabinet of the General Land-Office in Washington. The speci-
men was obtained by Colonel John H. Knight, United States Army, near
South Bitter Creek, Wyoming. Though consisting of a detached vertebra, it
especially attracted my attention from having previously seen no remains of
crocodiles in the large collections of fossils from the Tertiary formations of the
west.

The vertebra represented in Fig. 2, Plate VIII, belongs to the cervical
series, and resembles, both in size and form, the sixth or seventh of the Mis-
sissippi alligator. The bone appears to have been of mature age, and seems
thoroughly petrified. It has lost the greater part of its neural arch and
dependent processes, but is otherwise well preserved. From portions of
adherent matrix, it has been imbedded in a soft rock similar to that adherent
to some of the bones from other localities above mentioned. :

The body of the bone in its axis is 16 lines long; its height and breadth
in front are 14 lines. The hypopophysis, directed obliquely downward and
forward, as in the alligator, is about 5 lines long. “ Back of the process the
body is less prominently carinated than in the latter animal.

CrocopiLus ELLiottt.

The species thus named was originally designated from a specimen
obtained, during Professor Hayden’s exploration of 1870, at the junction
of the Big Sandy and Green Rivers. It consists of an upper-jaw fragment
containing two teeth and portions of two others, and is represented in Fig. 4,
Plate VIII. It appears to be the anterior portion of the left maxillary, con-
taining the fourth and fifth maxillary teeth and the fangs of the two succeed-
ing ones. The shape of the jaw-fragment is nearly like that of the corre-
sponding portion of the upper jaw in the mugger (Crocodilus palustris) of
India, but is more rugose on its exterior surface, and the palatine surface is

127

more vaulted. The teeth retained in the specimen have their crowns only
partially protruded. ‘They are proportionately more robust, or shorter and
_ Jess pointed, than in the mugger. Strong ridges define the inner from the
outer surfaces of the crown, which exhibits no indication of fluting, but the
~ enamel is finely and closely wrinkled longitudinally.

The space occupied by the teeth, from the fourth to the seventh inclusive,
is 35 lines. The entire length of the fifth or largest maxillary tooth is esti-
mated at about 24 inches. The protruded portion measures externally ? of
an inch in length, and its diameter at base fore and aft is 74 lines, and trans-
versely 64 lines.

Fig. 6, Plate VIII, represents a large portion of the upper part of a skull,
which has been attributed, but with no certainty, to the same species as the
foregoing. The specimen, in a number of scattered fragments without teeth,
was discovered, by Henry W. Elliott, on Little Sandy River, during Pro-
fessor Hayden’s exploration of 1870.

- The fossil indicates a form of skull very different from that of our alligator,
and is that ofa true crocodile. It approached in form more that of the mugger of
India cr of the Nile crocodile than that of the American crocodile, (C. ameri-
canus.)

The cranium above is remarkably flat; from its lateral borders defined by
the squamosals and post-frontals, and from the occipital border to the face in
advance of the orbits, it forms a nearly uniform plane with no depression of
the forehead nor eversion of the orbital margins. This uniform flatness is
also extended along the middle of the face to the muzzle. This and the
alveolar borders of the face are about as convex as in the mugger.

The sides of the muzzle are deeply notched at the conjunction of the pre-
maxillaries and maxillaries, and the bottom of the notch exhibits a conspicu-
ous recess for the accommodation of the large canine-like tooth of the man-
dible. A second and less conspicuous notch, as usual in the true crocodiles,

occupies a position about -the middle of the maxillaries.

The lateral borders of the cranium are less angular or more rounded
approaching the orbits than in the mugger and the American crocodile.
The superior temporal orifices are subrotund and nearly as wide transversely
as fore and aft. The intervening parietal surface is broad and deeply
pitted. The temporal surfaces of the parietal form a pair of deeply concave

recesses.

128

The anterior orbital border, as constituted by the prefrontals and lachry-
mals, is depressed or slopes inwardly toward the orbits.

The nasal process of the frontal is much prolonged, extending 2 inches
in advance of the position of the ant-orbital margins. The prefrontals are
proportionately long and narrow compared with those in the mugger. Their
length is about 4 inches; their breadth, where widest, is 14 lines.

The nasals are broad and flat at the back part. They are proportionately
of greater breadth than in the mugger. Their estimated length is 94 inches;
their breadth together in advance of the lachrymals is about 24 inches.

The fore part of the face, or the muzzle, has the same form as in the mugger
and other true crocodiles, but is proportionately less thick than in the one
specifically mentioned. The nasal orifice holds a more advanced position
than usual, so that the alveolar border in front is barely more than half the
extent it is in the mugger, nor is it perforated as in the latter and other true
crocodiles. The upper surface of the skull is everywhere exceedingly rugose,
with reticular ridges inclosing deep pits, and in some positions is deeply
scored by vascular grooves.

Four teeth occupied the sides of the premaxillaries, forming an unbroken
row. The intermediate pair are the larger and of nearly equal size; the
others are also nearly of equal size. The first tooth did not occupy the fore
part of the premaxillary as usual, in the true crocodiles, but is over an inch
from the position of the symphysis, close to the second tooth. A large recess
occupies the fore part of the palatine surface of the premaxillary, for the
accommodation of the first mandibular tooth, as usual in the crocodiles, but it
is closed or does not communicate by a perforation with the upper surface of
the premaxillary border. The recess holds a position internal to the first pre-
maxillary tooth. Smaller cenical recesses occupy the intervals internally of
the succeeding three teeth.

The maxillary appears to have accommodated fourteen or fifteen teeth, of
which the fifth one was the largest, as in other crocodiles. The fourth, in
comparison with the fifth one, was proportionately larger than in the mugger,
and the sixth was not much less in size.

The depth of the socket of the fifth maxillary tooth is full 2 inches; its
fore and aft diameter about ?inch. The depth of the fourth socket is 20
lines; its diameter 8 lines.

The premaxillary teeth, in comparison with those of the mugger, appear to

129

have been proportionately about as large. The anterior series of maxillary
teeth were rather larger, and the posterior series smaller.

Detached portions of both quadrates accompany the other portions of the
skull. They are somewhat peculiar in several anatomical points. The an-
terior surface is unequally divided by a conspicuous ridge, descending to
within an inch of the articular surface for the mandible. The grooved or
trochlear condition of the latter surface is much more decided than in the
mugger-or the American crocodile.

Measurements taken from the specimen above described are as follows:

Inches.
Length from ocei ue) PoLder tO Ghd Of MUZAZIC. 2. 2. ee eth bee ee ei le sh 20
Breadth of cranium at occipital border between prominent an ae of squamosals. 7
Breadth of cranium at postorbital angles....-. .. Be od Apna tals ala hs sk oo ai 54
Breadth of cranium between temporal orifices .....-...----.------.0 ----0-- Sl |
Pie TemeomiGgrehnead WepweenmlOLDilS.....0 226-2 ees weenie ee eee eee ees ses 14
eater me ORT OLA OUICES oa 2 cian a a a ek ee Ss a ee ee nec cows ween 13
Fore and aft diameter of the same.........-- hic Ae See Ae Pe te 9 al a JE sowie te 1%
Pi mena IO nA ry {yee ees. ot. ee ee ee Me Pe lees 24
Delp vau OW TLIGULIIL occ Sig 5 2 eee oc ee enn te Ds
Breadth of frontal where it joins the post-frontals.....,.....-..-2..2..-.----- =u 28
Momeraimoedih Crameber Of UNG OLDIES ..--. 502-2. cone ee eee eee eee tenes 23
Memermonrace im advance of the orbits <.. 2.0.2.2... 2202-5 ee tee dete eee 135
Breadth of face outside the fifth maxillary teeth....-.....-.-.---- 22.22.2402. 63
Breadth of muzzle as formed by premaxillaries .....--.......... oe SR reer Logie
Breadth of muzzle at notch back of the latter ..........-22...-....0......22.--- 4
Tony SLU ne TON eT e o ll OTe) ae ee ee a 6
IEPA ROE UNOCON ce ae tat Wasa clan a's Wale eels oie ae sean ha eee wie ss mee 24
istemmoraiiadiamever Of the SAME...--....-.- 22. eek eee eee eee twee eee nee 24
Thickness of premaxillaries in advance of the same...................-.-. hea! 3
Hstimated length of entire alveolar border ..........-...--.---- ----e0----0- 145
"Space occupied by the anterior five THPRIUIIR Vy ROGDIL etd Gace a oie vol ale aa Bate wate, 33
Space occupied by the pdsterior five’ maxillary teeth ...........2.......22. 0.22. 3
Breadth of articular surface of quadrate for the mandible.....................-. 24

A detached basi-occipital, obtained near Little Sandy River, may, perhaps,
belong to the same species as the preceding. The occipital condyle has
nearly as great a vertical as a transverse diameter, the former measuring 15
lines, the latter 17 lines.

The last summer Dr. Joseph K. Corson sent, as a gift to the museum of the
Academy of Natural Sciences of Philadelphia, a specimen consisting nearly
of the whole of the lower jaw of a large crocodile. He discovered the fossil
imbedded in a green sandstone in the vicinity of Fort Bridger. In removing

it from its matrix it was much broken, and most of the teeth were destroyed.
Siciae:

130

The left ramus in a restored condition is represented in Fig. 8, Plate VIII,
one-half the natural size.

The lower jaw belonged to a larger animal than the cranial specimen from
Little Sandy River, and probably pertained to a different species. The form
of the jaw is much like that of the mugger, but is of more robust proportions.
The rami, in their dentary portions, are much thicker in proportion to their
depth, and the symphysis is of greater extent, in this respect presenting a
greater resemblance to the condition in the American crocodile.

The dentary portions of the rami the greater part of their length are as
thick and thicker than the depth. Half way between the symphysis and the
median enlargement of the dentary portion of the ramus the thickness is over
2 inches, while the depth is 4 of an inch less. In the position of the enlarge-
ment just mentioned, the thickness is 2 inches and 2 lines, while the depth
is only 2 lines more. Thesymphysis has measured about 44 inches fore and
aft, and but slightly more than this transversely opposite the position of the
large canine-like teeth.

The splenial bone, as if to give greater strength to the ponderous jaw,
extends close up to the symphysis. The outer portion of the jaw in the posi-
tion occupied by the teeth, is more rounded than in the mugger. The back
portion of the jaw in form and constitution appears to agree with that in the
mugger. The outer surface of the jaw, strongly foveated back of the large
oval foramen, presents the usual vascular grooved and perforated appearance
in advance.

About eighteen teeth occupied each ramus of the jaw, but all are broken
from the specimen except one. Some of the broken and detached teeth
‘accompany the jaw. They appear to have been comparatively robust, short,
and blunt, conical in form, and but feebly curved. The enameled crown is
rugose and longitudinally grooved, but not properly fluted; the narrow grooves
separating wider convex and rugose longitudinal ridges. They sufficiently
differ from those in the jaw-specimen referred to Crocodilus Elliotti to per-
tain to a different species.

The end of the symphysis of the jaw or of the chin is broken away, so that
nothing can be ascertained in regard to the first pair of teeth of the two
rami. A large tooth, canine-like in its relative position and size, as usual in
the crocodiles, was number four in the series. The socket, occupied by

green-sand matrix, is about 10 lines in diameter. The expansion of the sym-

131

physis in the position of this socket indicates its canine-like teeth to have
been accommodated when at rest in a recess of the upper jaw at the junction
of the premaxillaries and maxillaries.

Succeeding the canine tooth alveolus, tliere are the remains and sockets of
five comparatively small teeth. Then followed several of the largest teeth
accommodated by the second expansion of the jaw. The socket for the
eleventh tooth is about the size of that of the canine tooth. In the left ramus
it retains the tooth, the apex of which alone had protruded. After this tooth
there followed a series of five others which successively decreased in size.

Measurements of the lower jaw are as follows:
Inches. Lines.

Memaninen Famil OL LOWER JAW .- ---..52---- 0st aew eens eceeen ese Ssh eee 20 6
Width of tower jaw outside the glenoid articulations.............--.--.- 12 0
Width of lower jaw a short distance in front of the glenoid articulations.. 13 0
Greatest width of symphysis. .---. EEE Re Sole 2k Oh ee 4 3
' Width of jaw at second enlargement, below the eleventh tooth -......--.. 6 0
Depth of jaw at oval foramen.........-.....---- eee See ee ee a oY TG
Depth of last tooth...... ea er ee SO Sele hice | s otebdidc gal =< 2 8
Le a GY CLOG (0 Oe eee eee ne ee a ee 2 t
fineuness below the eleventh tooth.....----. ------ +--+ o--sse. ee ee eee Z 2
Depron TAMUs MEAL SymphysiS.\.s2-..- 522-2. see ee ee eee eee 1 9
Thickness of ramus near symphysis. -.-. - - Sn aay ORS Sa PAE AE gees 2 2
Pemergo uM NY SIS TOLe: AMO Alb. 2 <= a 2 wo eine ee wate ew eee ene 4 3
ee ene OVOMOT EMCUIAtION....0---+----. ----s-eeee ee eee eee nee 2 7
Length of hook-like process back of glenoid articulation... . .- Peet 28 t 2 5
See ME MiIOUN ane TECH: sa: edad = wei sas ian ans icmp ae nem came enn os, B
Length of oval foramen... .. te PUN ae Riches Sc Diem ysica. 2 ss p 2 8
SMMPPMO NTIPTOLAMICN oi a 2s on nee ne we eee eke ene we ecw ecw ee ee eee OF DEL

Fig. 1, Plate VIII, represents the body apparently of a first lumbar verte-
bra; and Fig. 5 of the same plate, the proximal extremity of a left femur,
large enough to belong to the same animal as the cranium above described.
The two specimens were found together by Professor Hayden’s party near
Little Sandy River. They present no decided peculiarity distinguishing them
from the corresponding part in the living crocodiles. The shaft of the femur
contains a medullary cavity larger than usual in the latter, and in the specimen
it is filled with chalcedony.

The measurements of the specimens are as follows:

Lines.
Length of body of first lumbar vertebra beneath....-......-..-.2-....-....--- 20
eM MOMMOUNEAIILCEONym ne Lo. tt ke oe oe coe bee cee eee a ca eee 18
Pi Ginhron hodweanbeRionly as] o- Lees. seek 22 2c) Be LE. Qeee 2S dee » 18
NIT OLEL COMPLY SHI LONE LY 2t a STC] 0 5 eG ee 26

132

Fig. 3, Plate VIII, represents a specimen of a first caudal vertebra of a
smaller species of crocodile than those indicated by the preceding specimens.
It was obtained by Professor Hayden’s party near Little Sandy River. The
length of the body with its double ball is 214 lines. Several other vertebree
from Black’s Fork of Green River, and from near Church Buttes, Wyoming,
from their size and conformation, would appear to belong to the same species.

Order Chelonia

No other Tertiary deposit in North America has yielded such an abun-
dance of remains of different species and genera of turtles as the Bridger beds.
The fossils represent a large proportion of fresh-water and paludal forms; the
others pertain to land tortoises. Fragments of turtle-shells are the most fre-
quent of the vertebrate fossils met with, strewed on the bare tops and sides of
the buttes or among the débris at their base. Entire shells are comparatively
rare, and if they have been complete as fossils, they soon undergo disintegra-
tion after exposure on the buttes. Most of them have been much crushed,
while embedded, under pressure of the superincumbent strata, and now when
exposed from the softening of the matrix they readily fall to pieces.

The greater quantity of the turtle remains are referable to a species of fresh-
water terrapin of the genus Emys, the shells of which present sufficient variety
as to have at first misled me in referring them to several different species.
The next most abundant remains are those of one or two species of soft-shelled
turtles of the genus Trionyx, and after these the remains of a large land-tor-
toise. Besides the species and genera described in the succeeding pages,
Professor Cope has recently indicated a number of others from the same for-
mation.

TESTUDO.
Trestupo Corsont.

Among the many remains of turtles from the Bridger Tertiary beds are
those apparently of a large land-tortoise. Small and for the most part un-
characteristic fragments of the shell were obtained by Dr. Carter in 1869
and during Professor Hayden’s exploration of 1870, but it was nof until I
received the specimen represented in Fig. 7, Plate XV, that I recognized the
character of the species to which they pertained.

The last-mentioned specimen was discovered by Dr. Corson at Grizzly

133

Buttes. It consists of the anterior extremity of the under shield or plastron,
consisting of the fore part of the episternals and the end of the entosternal.
- The specimen might be supposed to belong to an Emys, but its resemblance
in form with the corresponding part in living species of Testudo leads me to
place it with this genus. The episternals project together rather abruptly
into a long, thick, and broad spade-like process, nearly straight at the front
border, but slightly notched at the middle. The projection behind is defined
by the outer extremities of deep grooves defining the gular and humeral scute
impressions. Its lower surface is strongly convex; the upper surface slopes
forward to the acute border of the process.

Back of the gular surface above, the plastron is deeply concave, but is not
excavated beneath the former as in the gopher, ( Testudo carolina.)

The end of the entosternal plate is impressed by the contiguous ends of the
_ gular scutes. The episternal process is about 2 inches long; its breadth at
base is 54 inches. The extremity of the process is 33 inches in width. The
thickest part of the episterna measures 14 inch.

The species I have named in honor of its discoverer, Dr. Joseph K. Corson,
United States Army, who to a love of his profession adds a special interest
in the promotion of the natural sciences.

During my recent trip to Fort Bridger I was so fortunate as to obtain a
number of additional specimens referable to Testudo Corsoni. Some of them
had been previously collected by Drs. Corson and Carter, and others were
found during our explorations of the buttes near Fort Bridger, and those of
Dry Creek ten miles from the former.

One of the best preserved specimens consists of a nearly complete ventral
shield or plastron, represented in Fig. 2, Plate XXX. This was discovered
by Dr. Corson at Grizzly Buttes, and presented by him to the Academy. In
the complete condition it has measured upward of 2 feet in length, and is
estimated to have been about 16 inches ‘in breadth to its sutural conjunction
with the upper shell.

In its form and proportions it resembles that of the living .Testudo radiata
of Madagascar more than it does that of the great Galapagos tortoise.

The lobes of the plastron are of nearly equal length and breadth. The
prolonged extremity or spade-like process of the anterior lobe is lost in the
specimen. The posterior lobe terminates in a deep, wide, angular notch
included by two angular processes.

The fore part of the anterior lobe is slightly bent upward and nearly straight

134

transversely. The plastron from the position of the pectoral scute impres-
sion backward becomes gradually and deeply concave. The deeper part of
the concavity is defined on the posterior lobe of the plastron by a narrow flat -
ledge laterally, which widens behind on the angular processes terminating the
plastron. The sternal bridges are moderately convex, and are wide fore and
aft.

The anatomical structure of the osseous plastron and the relative position
and number of its scutes are the same as in modern species of Testudo. —

The entosternal bone is subpyriform and wider than long. Its fore extrem-
ity reaches just in advance of the ends of the gular scute impressions, and its
back border reaches the groove defining the humeral and pectoral scute
impressions.

All the grooves defining the scute impressions are well marked, being deep
and wide. The proportions of the scute impressions are nearly the same as
in recent testudines.

The pectoral scute impression is longer at both extremities than interme-
diately. The groove defining it in front, commencing externally just in
advance of the bottom of the axilla, curves backward and inward, and then
turns forward and inward to the position of the back suture of the entosternal

plate.
The measurements of the specimen are as follows:

: Inches
Estimated length in median line to bottom of poststernal notch .........-... 2) ee
Estimated length on each side to ends of poststernal processes ...-..-..-...-.- 264
Hstimated: width oo 22:2 1. = pees oe ss wom ecinins eines cele Se ee aes ee oe 20
Estimated length of anterior lobe’ of omen: im median line. «-o-)te2 ieee 8
Length of posterior lobe of plastron in median line......--.-.-..----------.-- 5
ensth of posterior lobe of plastron laterally ..<- 2... -.2 2 -< 22. -- =. == 7
Width of anterior lobe at bottom of axille..-5./- 5-2. 2.2---5 0-2-2 = 12
Width of posterior lobe at bottom of inguinal fosse....-..-..-..------..--- [, UeOnS
Width at bottom of anterior prolongation of plastron...-....... 1 5
Width at ends of poststernal angular processes.....-.......-.----.---+-+----- 74
Depth of poststernal notch .....-...-.. eke siee ardour 24
Width foreand aft of sternal bridge. ----------------- 2 --- = ae 93
Length of entosternal plate .=...2222--:c2 e082 Jose ee ce ee ee 43
Wadthrot entosternal plate... 2 ajc ee =e ee ee oe oe 53
Length of hyosternal platein median line-2 22. .2 252-2... 32 2-22 se eee 64
Length of hyposternal plate in median line.--..-.-.--...---.-.2 2... 52s 53
ihength of xiphisternal plate in’median line~-=—-.2---.-------- .--- === . 48
Length of pectoral scute impressions in median line.......-...---.---..--.---- 13
Length of pectoral scute impressions where narrowest........---.. .; See 1
Length of abdominal scute impressions in median line ...............-...-..-- 9

Length of femoral scute impressions in median line........:-....-.---.-------- 33

TInehes.
Length of caudal scute impressions in median line....!.-......--- fe. sa 24
Thickness of plastron at base of anterior. prolongation......- ...-------------- 13

_ Thickness of anterior lobe laterally near bottom of axilla.......-.--..-..--.--- 1
Thickness of posterior lobe near bottom of inguinal fossa...-.--.----- sept Nee sete 18
iinekness of plastron near the ¢enber-.----.--.----.--- 22-22. 22-2 = 2 a2 = ee 2

During a day’s excursion to Dry Creek Buttes, ten miles from Fort Bridger,
Mrs. Anna Carter, the wife of Dr. Carter, who accompanied us, discovered a
large turtle partially imbedded in a green sandstone on the top of a butte.
The upper shield had been destroyed by recent exposure, but the nearly com-
plete plastron was obtained by removing the cast of the shell above it. The
sutural connections of the bones are somewhat obscured by the firm adherence
of particles of sand. It retains the anterior spade-like process nearly entire,
and this is represented in Fig. 4, Plate XXX.

The specimen presents some differences from the former, which, however,
I have not regarded as specific, though they may be so. The spade-like pro-
longation of the plastron is more abrupt and considerably longer than in the
fragment upon which the species was originally founded. The fore part of
the anterior lobe of the plastron approaching the lateral border along the
groove defining the gular and humeral scute impressions is much more convex
than in either of the preceding specimens. From the position of the entoster-
num backward, the plastron becomes concave, as in the former specimen, but
the concavity is comparatively shallow. The poststernal notch is also of less
depth than in the previous specimen, but otherwise the plastron is sufficiently
like the latter to pertain to the same species.

The measurements of the specimen are as follows :

Inches.
onernson plastron in median line ..-...0.... --.--+- -----+-- eee a me 25
rs Ne OunM aSbrOMLOM CACM SOG voc caw wca nce ig mesic once yee eee eee nee eee e ec nes 264
Width of plastron at middle, estimated at about.......-.....-.---.- .-...---. 20
Emu mca NORLOR OMG. ons <i ancinmi 5 Sooke = in 64 no 2 ae esses hae es 2 ee Cis 9
Menino posterior lowerah Middle <-...j...0<c< +. 02 --- esos eee eee cec sence 6
‘Length of posterior lobe to ends of angular processes .-.... .-..-----.-------- 84
MM mOleAOTLOMOQO Ati DAS)... ¢ 2s .5 cee weed ence en ones pee nee eeee eect se 12
PRA eCmNOSVenOr LOW at) PASO. ol. <5 -'s. seein een le Se ee cies woe aecewn see acne 114
enechonepirstermal prolongation .....-...---s.+--2.secee se eeee gene ce ee cece 24
Width of episternal prolongation at base .........--..-- Mein 8 Saber eae 54
Width of episternal prolongation near end .......-...----..----------- ccee Se
innerdin om stermaleWrdees fore-and aft... ... --0--. sacs eens eee ceeciceees sees 9
Breadth at ends of poststernal angular processes ...-..------ CRS ERP eee 74
MEMES Ole OSESTEMMAMMOC Mesa) <iniaa Vnii- 4)an hye dere ge nea ecleSe aces ds eee ee s's opie sets EES
Length of entosternal bone ........ Sm 22) arn ee eRe SS cs eae 43

PMEAGhntO ENntOstenmalpMOMGye ccc du < ~~ <2). -c- nee sme ewe ses cose eset ene 5$

13

In some low buttes on the road to Carter Station, about three miles from
Fort Bridger, Dr. Carter found a large turtle, which I viewed as pertaining
to Testudo Corsoni. As it lay partially exposed it measured about 2 feet 4
inches in length, and approximated 2 feet in breadth. It was so much
broken that in the attempt to remove it, it fell into a multitude of fragments.

In Dry Creek Cation we discovered another turtle, which I viewed as T.
Corsoni. The shell was in great part decomposed, but the rock which had
occupied the interior still preserved its form. From this cast we estimated
the shell to measure 28 inches long, 20 inches broad, and 14 inches high.

Another specimen of a large turtle, discovered by Dr. Corson on the buttes
of Dry Creek, consisted of fragments of a plastron with a few marginal plates
of the carapace. The plastron, of which we have been enabled to restore
the greater part of the anterior lobe, presents peculiarity enough to pertain
to a distinct species from TJ. Corsoni. It was about the size and proportions
of the plastron attributed to the latter, but the episternals are neither so
abruptly nor so much prolongéd as in the former specimens, and the front
part, as represented in Fig. 3, Plate XXX, is decidedly notched. The under
surface of the extremity of the anterior lobe is flatter.

The bony construction of the plastron, so far as preserved, is the same as
in the former specimens, and the entosternal is nearly of the same size and
shape. |

The scute impressions are also the same as in the former specimens, except
that the pectoral scute impressions are nearly twice as long.

Fragments from the back lobe of the plastron retaining the bottom of the
poststernal notch indicate this to be more acute than in the former speci-
mens. 3 .

The measurements of the specimen are as follows:

Inches.
Length of anterior lobe of the plastrom-.- 62.2 - sana 222 eee 24 eee 8
Sree Ol LANG JOS Oe bering sono dsopou, <Sone st bose sed once sooedea snuesane sss2ccc- 103
lene th of episternal proloneatiom-es ass] +63. -) 5. -) eee eee 13
Breadth -of episternal prolongation at base .-.-....-..--..--.--2-. -+--te haces 53
Breadth of episterpal prolongation near the extremity .....--..--.-.-.--...--- 44
Length of entosternal plate ...-...-..---.-.--.-...- ee ee ees =. - 45
Breadth of entosternal plate .....-.......--..-. Dea Mecine ne ye oat See 54
Length of:cular scute impressions. =: ..... >. -c- eee es nee te eee 34
Henesthvotehumeral Sscute 1mpressions=es. ceases = oe == eee eee 3: 43
Lenesthvof pectoral’scute impressions: -o. 2 ...2--- 622. 5- = = sos) oe 2 eee a

Length of pectoral scute impressions where least........-...---..------.----- 2

137

Portions of the shell of another specimen, apparently referable to Testudo
Corsom, were discovered by Dr. Corson on Dry Creek Buttes. Several of
the fragments so far recompose one side of the back lobe of the plastron as
to determine its identity with that of T. Corsoni. It is especially interesting
from its being accompanied by a number of fragments of the upper shell,
which being reunited compose the middle portion, as represented in Fig. 1,
Plate XXX. This specimen tends to confirm what I have latterly suspected,
namely, that the specimens formerly described and represented in Plate XI,
under the name of Emys Carteri, really belong to Testudo Corsoni. The
specimens originally referred to the former, though much more complete
than the one upon which the latter was founded, completely misled me. The
spade-like process of the plastron was not simply broken off, but, while
imbedded in its matrix, was crushed or squeezed off in such a manneras to
leave but little trace of its true character. The accompanying portion of the
carapace exhibited the costal plates with strong costal capitula as in living
species of EKmys. This emydoid character with others are probably suffi-
cient indications that the specimens would properly be referable to a genus
distinct from either Testudo or Emys, and is probably the same as that
recently proposed by Professor Cope, under the name of Hadrianus.

The specimens originally referred to Emys Cartert, but now viewed as
pertaining to Testudo Corsoni, were discovered by Dr. Carter in the buttes

near Fort Bridger. They consist of the greater part of a mutilated plastron
with the ends broken off, and the anterior median portion of the carapace.

The plastron represented in Fig. 1, Plate XI, resembles, in its size, form,
and proportions, the nearly complete specimen above described and repre-
sented in Fig. 2, Plate XXX. It is not so concave posteriorly, but other-
wise presents nothing peculiar.

The portion of the carapace represented in Fig. 2, Plate XI, consists of
the nuchal and anterior three vertebral plates with fragments of the contig-
uous costal plates.

The anterior border of the fragment is slightly emarginate. The vertebral
region is flat, and slopes forward. from the anterior half of the first vertebral
plate. The nuchal plate is nearly as long as wide, and its antero-lateral
borders are moderately convergent.

The first vertebral plate is clavate in outline with the broad end behind.
The anterior narrow end dips into an emargination of the nuchal plate. Its

widest part is less than a fourth of its length in advance of its posterior
18 G

138 °

border. The second vertebral plate presents the usual hexagonal coffin-like
outline, but in a reversed position, its broadest part being about one-fifth of
its length in advance of its back border. The third vertebral plate is oblong
quadrate, with the fore and lateral borders convex, and the back one nearly
straight.

The sutures defining the first costal plate depart from the anterior narrow
end and the posterior widest part of the first vertebral plate. The scute
impressions of the carapace are well defined by deep grooves.

The nuchal scute impression is flat, and widens anteriorly. The first mar-
ginal scute impression is wider than long.

The first vertebral scute area is longer than broad, and is purse-like in
outline. :

The second vertebral scute area is also longer than broad, and is quadrate,
with the lateral borders nearly parallel.

The fragment of the carapace from its front border to the back border of
the third vertebral plate measures 134 inches.

_ Other measurements of the carapace are as follows:

Lines
Length of nuchal plate.......... Poiana Skeet lene eee BoE xe se + afl eee 56
Breadth.of nuchat plate inwgront 2.25.05. bee |. sibs 5s Sans ine eee 44
Breadth of nuchal plate where widest ......-. Heretiene Sia Sch aed ia coe Ores vey OO
Length ofmrstivertebral plate. S00. aoc soe = eee ts Sie ees 48
Breadth of) first vertebral plateim fronts: 2.2.5 22-2 o..2 ! se es ee 9
Breadth of first vertebral plate where widest------:...................--------. 30
Breadth of first vertebral plate at back border.......-.......-.-.--.-.-«.------ 14
Length of second vertebral plate .-..- ie be we eee ee ees oe Nectld elie 27
Breadth of second vertebral plate where widest.......-..-...-------.------.--- 26
Breadth of second vertebral plate at back border -..................-..--- cae. ae
Length of third vertebral platezs2- <7 .2t<-sec0s+ «75-22 eneiee | ee eee Sse 28
Breadth of third vertebral plate at middle -..-....5-22 2.5 +-2-5-.- 0.2. - eee 22
Breadth of third vertebral plate at back border.............--..-...--.-sesesae 17
Kength of nuchal scute impression | ~~~ -6----+ 2: 2eed-a. 4. 2 21
Breadth of nuchal scute impression in front .........---.-- soe cea eet 11
Breadth of nuchal scute impression behind -2------.--..+--.- 225... ese 6
Length of first marginal scute impression..... Wieciale oot oa aces so lie =e 26
Breadth of first marginal scute impression behind ....................--------- 38
Length of first vertebral scute impression.....-..-.-.- REESE RAI ~~~ 67
Breadth of first vertebral scute impression in front --...........-.......-2 12-2: 32
Breadth of first vertebral scute impression near middle .......-.......--------- 52
Breadth of tirst vertebral scute impression at back border............-..-....-- 43
Hengthvof-second vertebral seute impression «-<- =----+----.-----.-5=-52=5 see 58
Breadth of second vertebral scute impression at middle ........-..-....--.----. 48

The accompanying plastron measured, in its complete condition, upward
of 2 feet in length and about 14 feet in breadth.

¢

139

_ Other measurements of the specimen are as follows:

Lines
Wii ofanteror lobe of plastrom at base: 22.2.2: ..--55-.-2-5.-2<2---5. 55 ceee 108
Wwadth! of posterior lobe of plastron at base...-..-..--..-2-02--6--+2e sue ee cee 120
Breadth of sternal bridges fore and aft: .:......2:2.2--..2-.-42-.-- Fie Gos oa 114
Length of entosternal plate .....-...........-- Ba gs SER RE Cree ee Se 56
Hereadth of entosternal plate .......-....-..---1-.+--- ee ee se OS
Length of hyosternals in median line of plastron...... Te ek ARONA NORE IETS. 52, 60
Length of hyposternals in median line of plastron......---- ++ .......----------- 61
Length of humeral scute impressions ................-.-- Oh) ce i ooo 48
Mensthivot Pectoral SCULE IMPKESSIOUS .. 2... 2. .--+---sie cee e nee ceed eres nate 26
enerh ot ‘abdominal seute impressions’. -2..0.-2. 5.22500 boc ences ee bese eee nk 2
Length of femoral scute impressions ....-........-..--------0-- sete Pee? sh. Sh 47

The portion of a carapace represented in Fig. 1, Plate XXX, and previ-
ously referred to as tending to confirm the impression that Emys Carteri was
the same as Testudo Corson, retains most of the vertebral plates with contig-
uous fragments of the costal plates.

The anterior three vertebral plates, corresponding with those w ied: are
retained in the specimen originally referred to Emys Carteri, have the same
form, but are wider. The succeeding two plates have the same form as the
second vertebral plate in a reversed position. The sixth vertebral plate is
too much broken to ascertain its exact form, but it would appear to be nearly
the same as those in advance. The seventh plate is hexagonal, with the
breadth more than twice the length ; ‘and the eighth plate has the same form,
but is not so broad.

The length of the fragment of the carapace from the anterior broken end
of the first vertebral plate to the back border of the eighth plate is 16 inches.

Other measurements are as follows :

Lines.

Heneth of first vertebral plate, estimated.-........--. .--... eee eee e- eee eee ees 40
Ere xounrOumiirsh vertebral plate im fromb...'5..-2.2:..c-ccss-s dec cccees Soeee eee 14
Breadth of first vertebral plate where widest .-....- APIS MPI E Rope Ea Le a 31
Breadth of first vertebral plate at back border ..-.....-.-........----.---.--+ 7
Length of second vertebral plate. -... ees Paths ac eee ae ane stag a tet te 8 arenes 27
Breadth of second vertebral plate where widest.......:-.-..----.-----+-------- 28
Breadth of second vertebral plate at back border.........-....-.-----.-------- 18
_ Length of third vertebral plate BE ck Sere are ata a aren fe a etna sei ee ne een 28
Breadth of third vertebral plate at middle .................- ee eee oer hao
Length of fourth vertebral plate.................---.-.- I: for kg 6 Ae 26
Ercadimontounthavertebral platerin, front. --.2..-..-.<./---~-en ele ete e sec eeee 29
JD sSianSh ie, COURMAU a, YOLEN 0) Ee a ear a Sn 24
Bread Onmahinverte oral plake IM trONb..-..5--s---n5-c2--5----0--522-- lessees 27

Menorhvote sixtimeversebraleplaters.. 6 cio .ie tse coe cease bec oelhclewsiceeces ae elles 20

140

Lines.
Length of séventh Vertebral Pigte ee - - cn neat ple tn a aly oo 13
Breadth of seventh vertebral plates... --- sai oe eee Mcitin ies oie eo oes c ee 28
Length of eighth vertebral plate. ..:.-........ BP (ee SE Se a 13
Breadth of eighth vertebral plate <- + <im 4-4. -snage baie ns ee OE 2 24

The costal capitula of Testudo Corsoni appear in the specimens as robust
conical eminences, with a broad, expanding base, and are proportionately
better developed than in living species of Testudo, and even many of the
species of Emys.

Figs. 2, 3, Plate X XIX, represent the upper extremity of a humerus, and Fig.
4 the lower extremity of a femur, which were found in association with the
fragment of a carapace last described, and may reasonably be supposed to per-
tain to the same animal. - Both fragments resemble the corresponding parts
of a modern Testudo.

The head of the humerus has an inner trochlear extension, as in recent
species of Testudo. Independent of this process, the transverse diameter of
the head is nearly as great as the fore and aft diameter. In the specimen it
presents a discoidal, flat surface, but this is evidently accidental.

The measurements of the specimens are as follows :

Lines
Breadth of humerus between tuberosities’ ---2s-222.5: 22.22 22-2) 2 oe eee eee 29
Breadth between outer tuberosity and inner extension of the head..-........... 32
Breadth of the; head withitspmner trochlea.-..- 5. -- 25. ee eee 20
Fore’and'aft'‘diameter of- the head’:-.2....5 2. o--:o.<ssce2 soos) oo 17
Breadth of thée'distal end ofthe femur). 2.2.2.2... 022 2) eee 24

EMYS.

EMys WYOMINGENSIS.

Of the many remains of turtles from the Bridger Tertiary deposits I have
had an opportunity of examining, most of them appear to me to belong to a
species of Emys, which presents so much variation in anatomical details that
the first specimens brought to my notice were viewed as pertaining to no less
than four distinct species. ‘These were named Emys wyomingensis, E. Steven-
sonianus, E. Jeanesi, and E. Haydeni. A subsequent examination of ad-
ditional specimens, collected by Dr. J .Van A. Carter and Dr. Joseph K. Cor-
son, United States Army, and presented by them to the Academy of Natural
Sciences of Philadelphia, has led me to regard all those indicated under the
above names as really pertaining to a single species. J admit that I may be
wrong in this determination, but if such is the case, it would appear that
almost every specimen presents characters to distinguish a species.

141

Regarding all the specimens under consideration as pertaining to a single
species, this would retain the original name of Emys wyomingensis.

The composition of the shell so far as relates to the attachment of the
carapace and plastron, the number of bones or plates and the number and
relation of the corneous scutes, is the same as in living species of the genus
Emys.

In the mature condition, the shell of Emys wyomingensis is upward of a
foot in length, with about three-fourths the same measurement in breadth.

To what degree the shell varies in form, that is to say in relation of length
and breadth with the height, and in outline, cannot be determined from the
material at command, on account of the imperfection of the specimens, or
their distortion from the original condition, due to pressure or to a crushing
force applied to them while imbedded in the strata from which they were ob-
tained.

The elements of composition, especially the vertebral plates and scutes,
differ more or less in different specimens, both in form and in the relation of
length to the breadth. While the length of the vertebral scutes in general
exceeds the breadth, especially in the case of those intermediate, in some
specimens even to the extent of being a third greater, it nevertheless varies
so much that in some instances it barely exceeds the breadth. The verte-
bral plates vary in the same manner in different specimens, nor does this
variation always accord with that of the same character in the vertebral scutes,
that is to say the elongation of the scutes is not always accompanied in a
proportionate degree with elongation of the plates.

1. Emys wyomingensis. was originally described from an isolatéd episternal
bone, sent to the writer by Dr. Carter. It was the first of the remains of
turtles from the Bridger Tertiary deposits, which could be referred to the
genus. It is represented in Fig. 5, Plate IX, and exhibits the usual form of
that in living species, but further presents the appearance of being impressed
by a narrow intergular scute. The presence of the latter I suspect to be ac-
cidental or anomalous, though it may be normal, and may really indicate that
the fossil belongs to a species distinct from those which I am now disposed
to view as the same. The front of the specimen is truncated and slightly
notched at the outer part.

2, 3. Emys Stevensonianus is the name originally given to a supposed
species founded on the specimens represented in Figs. 2,4, Plate IX. These

142

were collected by Dr. Carter in the vicinity of Fort Bridger, and sent to the
Smithsonian Institution, whence I obtained them for examination. The
specimens consist of portion of a carapace, Fig, 2, and portions of two plas-
trons, Figs. 3, 4. Slight difference in the corresponding portion of the latter
specimens with that attributed to L. wyomingensis, but especially the absence
of any evidence of an intergular scute, led to their being referred to another
species. | .

The sternal specimen, represented in Fig. 3, accompanied the portion of a
carapace, represented in Fig. 2, and from its appearance was assumed to have
belonged to the same individual.

In the sternal specimen just indicated, the entosternal plate is lozenge-shaped
in outline, but constricted at the middle of its posterior part. Its length is
equal to the breadth, but the evidence from the isolated episternal, first re-
ferred to EL. wyomingensis, is that its entosternal was wider than long.

The divisions of the plastron and its impress by scutes, as seen in thé more
perfect specimen, appear to agree pretty closely with the arrangement ob-
served in ordinary living emydes.

The second sternal specimen, represented in Fig. 4, was supposed to per-
tain to the same species as the former one, though exhibiting differences
which rather approached it nearer to that first referred to E. wyomingensis,
except that it exhibited no trace of the existence of an intergular scute. The
entosternal bone is wider than. long, and without conspicuous constriction at
its posterior part. The anterior truncated border of the episternum is con-
spicuously notched at its outer part.

In all the sternal specimens indicated, the gular and humeral scutes have
doubled over the edge and extended upon the upper surface in the same man-
ner as in living emydes.

In the carapaceal specimen, Fig. 2, the vertebral plates, consisting of the
series from the first to the eighth, inclusive, successively decrease in length
except that the third is-a little longer than the second, and the fourth and
fifth are nearly equal. ‘To the fourth inclusive, the length much exceeds the
breadth, but they successively diminish in this proportion. The fifth is but
slightly longer than wide, and the remaining plates are much wider than long.
The second and fifth are of the same width, and in this respect exceed the
first and intermediate ones, which are likewise of nearly uniform breadth.
The sixth plate is the widest of the series; the others successively diminish.

143

They exhibit the usual forms, the first bemmg oblong with the borders convex
outwardly, the others to the fifth being wide coffin-shaped, and the remaining
ones are more regularly hexagonal.

The second and third vertebral scute-spaces are quadrate with the lateral
defining-grooves strongly double sigmoid. ‘The second space is broader than
long, but the third is the reverse.

4. It was the nearly complete shell, soptdentad in Plate X, which was
attributed to a different species from the former specimens, under the name
of Emys Jeanesi. "This fine fossil was obtained near Fort Bridger, Wyoming,
during Professor Hayden’s exploration of 1870. It is considerably distorted
from pressure, the right side being crushed inwardly so as to be nearly ver-
tical. The shell, completely petrified like all its associate fossils, is filled
with a greenish-gray sandstone. Its prominence or convexity in the original
condition was perhaps not greater than in some of the ordinary living emydes,
but it is apparently more prominent, from the lateral pressure to which the
shell has been subjected.

The carapace is oval in outline with the borders moderately deflected,
acute, and without conspicuous indentations, except that it is slightly notched
in the position of the. nuchal plate. The plastron has the same form and
degree of development in relation with the carapace as in living species of
the genus. It is truncated in front, and notched behind.

Although the sutures of the shell are conspicuously visible, the bones or

plates are all closely united, and the specimen appears to have been nearly or

quite in the.adult condition. No lines of successive growth are visible on the
plates, which are everywhere smooth. The position or boundaries of the
scutes are indicated by deeply marked grooves.

Ten vertebral plates appear to constitute the series, the connection of the
last two in the specimen being destroyed. In -form and proportions they bear
a near likeness to those in emydes in general. They are rather wider pro-
portionately than those in the specimen first referred to E. Stevensonianus,
but otherwise are sufficiently alike to pertain to the same species.

As usual, the first vertebral plate is longest; then follows the third. The
second, fourth, and fifth are nearly equal. The others, to the eighth, succes-
sively diminish. The second vertebral plate is as wide at its fore part as it
is long, but the succeeding two plates are considerably longer than wide.

144

The fifth is as wide as it is long, and the remaining plates are considerably
wider than long.

The costal plates have about the same form as in recent species of the
genus, but the first one is of greater proportionate breadth. Besides the
nuchal plate, it articulates with four marginal plates. The remaining costal
plates are of nearly uniform width as in recent emydes.

The second costal plate articulates with the fourth and fifth marginals ;
the third, with the fifth and the anterior angle of the sixth marginals; the
fourth, with the sixth marginal alone; the fifth, with the sixth and seventh
marginals ; the sixth, with the seventh and eighth marginals ; the seventh, with
the eighth to the tenth marginals inclusive, and the eighth with nearly the
whole of the tenth and the angle of the eleventh marginals.

The marginal plates have nearly the same form and proportions as in recent
emydes.

The nuchal plate also has nearly the form and proportions as in the latter.
The pygal plate, likewise, has the same form, but is proportionately smaller.

The vertebral scute-tracts have nearly the same form as in living species of
Emys, but the intervening ones are longer than wide. They are proportion-
ately somewhat narrower than in the specimen first referred to E. Steven-
sonianus.

The first vertebral scute at its fore part extends outwardly nearly to the
line between the first and second marginal scutes, and in this position is
widest.

The last vertebral scute, at its posterior border, crosses the last vertebral
plate a short distance back of the middle. In recent species of Emys it.
impresses the pygal plate.

The costal scutes resemble those of ordinary emydes, and as in these
impress the marginal plates at their conjunction with the corresponding scutes.

The nuchal scute is comparatively short and wide. The specimen being
imperfect at the back part prevents us from ascertaining positively whether
there existed a pair of pygal scutes as in living emydes, but an apparent curve
upon the bone renders it probable that two also belong to the extinct species.

The marginal scutes resemble those of recent emydes, but the anterior are
wider than high, and the posterior, including the pygal scutes, are higher
than wide.

The fore part of the plastron has a half-oval outline slightly projecting, and

145

truncated at the extremity as in ordinary emydes. The back part likewise
has the same form as in the latter, and is also notched at the extremity.

The pedicles are less elevated than in most recent emydes, and are rather
wider to the acute border of the carapace.

The constitution of the plastron is so nearly like that of ordinary living
emydes as hatdly to need special description.

The entosternal plate is nearly lozenge-shaped, and is widest transversely.

The humeral scutes ‘at their posterior border barély cross the posterior
extremity of the entosternal bone.

The pectoral and abdominal scutes extend outwardly to conjoin the margi-
nal scutes upon the marginal bones. In ordinary recent species of Emys the
marginal scutes extend upon the hyosternal and hyposternal plates to join the
pectoral and abdominal scutes.

The axillary and inguinal scutes are large, and impress each a marginal
‘and a sternal plate.

The length of the carapace in a curved line is within half an inch of a foot
and a quarter ; its breadth, in the same manner, 11 inches; ina straight line
it is little over a foot in length and about 10 inches in breadth. The plastron
is less than a foot in length, and its pedicles measure, fore and aft, 42 inches.

5. The specimen originally referred to Emys Haydeni is represented in
Fig. 6, Plate IX. It consists of a portion of the carapace attached to a mass
of indurated clay, and was obtained near Fort Bridger, Wyoming, during Pro-
fessor Hayden’s exploration of 1870. Since the specimen was figured, addi-
tional portions of the shell have been found which allow the restoration of
the fore part of the carapace. It belonged to a larger individual than the
specimen first attributed to EL. Jeanes?, and from the appearance of the mar-
ginal border of several of the costal plates to a less mature one.

The form of the carapace in front and its constitution in detail are very
similar to the corresponding portion in the former specimen attributed to L.
Jeanesi. 'The proportions of the vertebral plates is more nearly as in the lat-
ter than in the specimen attributed to LZ. Stevensonianus.

An apparently important difference between the fossil under examination
and the one attributed to E. Jeanesi is the less uniformity of width of the
intermediate costal plates. These alternately become wider and narrower
toward their outer extremities, whereas in the specimen referred to EF. Jeanesi
they are nearly uniform.

19 6

146

As peculiarities of the fossil, the fourth vertebral plate is octagonal, and
the fifth one in consequence quadrate.

The second and third vertebral scute-tracts are much longer than wide,
and proportionately much longer than in the former specimens. The anterior
division of the second vertebral scute forms three sides of a square; and the
posterior groove defining the third scute crosses the sixth vertebral plate
instead of the fifth ds in the other specimens.

The peculiarities indicated in the fossil under examination I regard as being
of an individual character and in some degree anomalous. |

A fragment of the fore part of the plastron accompanying the specimen
referred to E. Haydent, and apparently belonging to the same individual,
resembles the corresponding part in the specimens previously described, but
is not notched at its anterior truncated border.

6. Another specimen, referable to Emys wyomingensis, consists of a nearly
complete shell except the posterior third of the carapace. It was discovered
by Dr. Carter in the bluffs of the Cottonwood, seven miles from Millersville, -
in the vicinity of Fort Bridger, Wyoming, and presented by him. to the
Academy of Natural Sciences of Philadelphia. It is occupied in the interior
with a greenish-gray sandstone, including indurated clay pebbles. In form
and size it approaches closely the specimen first referred to Emys Jeanesi.
In the form and proportions of its vertebral scute impressions it more nearly
resembles the specimen originally referred to E. Haydeni. The intermediate
ones are, however, more strongly double sigmoid at their lateral borders; the
fore part of the second vertebral scute is less square; and the anterior border
of the third is strongly bowed forward instead of being nearly straight.

An accidental fracture of the specimen across the posterior third exposes
to view the lateral supports of the carapace ascending from the plastron.
These are much wider than in any of the living emydes, and approach in their
proportions those of the living fresh-water turtle Batagur, of India.

7. A seventh specimen of . wyomingensis consists of an intermediate por-
tion of a carapace and nearly the whole of the sternum. It was obtained by
Dr. Carter in the vicinity of Fort Bridger, and presented by him to the
Academy of Natural Sciences of Philadelphia.

The vertebral plates of the carapace are in general of proportionately greater
breadth in comparison with the length than in the former specimens, and in
this respect most nearly approach the one which was referred to L. Hay-

147

deni. The vertebral scute impressions likewise most nearly resemble those
of the latter but are proportionately broader, and the posterior border of the
third vertebral scute crosses, as usual, the fifth vertebral plate.

The interior of the carapaceal specimen being freed from matrix, exhibits
the costal plates with strong, well-developed costal capitula.

_ The plastron is flat; rather more strongly notched at its posterior extremity
than in the former specimens in which it is preserved. t
* The thickness of the costal plates ranges from 2 to 4$ lines. The thick-
ness of the hyposternal plates internally ranges from 54 to 84 lines.

8. An eighth specimen, consisting of the greater part of a plastron with
fragments of the carapace, was obtained by Dr. Carter near Lodge-Pole Trail,
thirteen miles southeast of Fort Bridger, and presented to the Academy of
Natural Sciences.

y. A fragment of a carapace, from Grizzly Buttes, presented to the Acad--
-emy of Natural Sciences by Dr. Joseph K. Corson, United States Army,
has the intermediate scute impressions much longer than the width, not more
so, however, proportionately, than in the nearly complete specimen numbered
as the sixth.

10. A similar fragment of an apparently young specimen, presented by
Dr. Carter, has the second vertebral scute impression nearly equal in length
and breadth; and the third one is but little longer than the breadth. Their
lateral grooved borders are strongly double-sigmoid.

11. Part of a carapace and plastron of a still younger specimen, obtained
by Dr. Carter near Lodge-Pole Trail, twelve miles southeast of Fort Bridger,
nearly agrees in the form and proportions of its corresponding vertebral scute
impressions with that last described. The second is nearly of equal length
and breadth; the third and fourth are wider than the length. In its details
of structure it accords sufficiently with the older and more complete specimens
to render it probable that it pertained to the same species, except that the
carapace is obtusely carinated its entire length. The entosternal bone is more
rounded at its fore part than in previous specimens, and its length is about
equal to the breadth. ~

12. A fragment of a plastron of another young individual, from the same
locality and gentleman as the preceding, nearly agrees with the corresponding
part. The entosternal is a little longer than broad, and is pyriform, with lat-

eral projecting angles.

148

13. A specimen, apparently of a still younger individual of the same species,
presented to the writer by Dr. Carter, was about the size of the palm of the
hand. It consists of small portions of the carapace and more than half the
plastron. The carapace is carinated as in specimen No. 11, and otherwise
agrees with this in its details. The plastron has the same form as in the
more complete and older specimens previously indicated, but the entosternal
is more pyriform, considerably longer than wide, and the posterior ase
groove of the pectoral scute crosses its middle. P

If it is admitted that the specimens Nos. 11 and 13 belong to Emys
wyomingensis, it would appear that the carinated condition of the carapace is
a juvenile character, disappearing with growth. It would also appear that
during growth the breadth of the entosternal plate became proportionately
greater in relation with its length.

None of the specimens viewed as young ones exhibit upon the surface lines
of growth, except the sternal one, No. 12, in which they are feebly marked.
A distal fragment of several posterior costal plates of specimen No. 11, in the
immature appearance of its border, clearly proves its youthfulness.

Besides the thirteen characteristic specimens of L. wyomingensis which
have been described or mentioned, fragments of many others are contained
in the collections I have had the opportunity of examining. From their com-
parative frequency, this appears to have been the most abundant of the fresh-
water turtles of the Bridger Tertiary epoch.

14. Since writing the foregoing, I have had the opportunity of examining
another specimen of Emys wyomingensis in- the possession of Dr. Hiram
Corson, which was sent to him from Fort Bridger by his son, Dr. Joseph K.
Corson. The specimen consists of a nearly complete shell except the posterior
fourth of the carapace. It is a little smaller than the fourth-described speci-
men, represented in Plate X, and is crushed and distorted nearly in a similar
manner. :

The most striking peculiarities of this, which may be distinguished as the
fourteenth specimen, are the unusual depth and width of the scutal grooves
of the carapace and the proportionate shortness and breadth of the costal
scute areas. ie

The intermediate vertebral plates to the first and fifth are absolutely longer
and narrower than in the rather larger fourth-described specimen. The costal
plates are shorter, and the second to the fourth, inclusive, are broader. The

149

first and second vertebral scute areas are wider and the third one longer.
The forms of the plates and scute areas indicated are nearly the same in both
specimens.

The plastron is slightly convex in both directions, and its extremities for
‘half the length are more parallel at the lateral borders than in the fourth-
described specimen. The axillary and inguinal scute areas are longer and
narrower than in the latter, and somewhat modified in form. The length of
the plastron in the median line is 11 inches. Other measurements in detail
are given in the annexed table under the head of specimen 14.

Comparative measurements of the specimens referred to Emys wyomingen-
sis are as follows:

es

fee een ee ear cage fae me | ig creams apne Sane n ponece ssa cen gene soars assshe gaurd tanqoqzes {ITS jo PQprorg
see rS AS sgss ise Sl" “QUER acae |= oe epee |e Dor te Te eo OLR Ge eae tO mel eee ope sce “oo seoss= ogurd [erqoaj10A TIYSIo Jo yySuoT
Emits seipee|sseeee] go [eamenetacsmsadememce| py eeseee| gy SPs Glee eee ee ee seroquld qerqencos MiueAes Fo qpuerg,
En ae wesese|eeceee] gp [ee eee-]-- Saal Base fg |[------] og Te PESehS]) @e “isoscrinlocho mete Slmacic.ceiaciag COE DOC oyV[d [waqaz10A Y}UoACS Fo TySuoT
7 ee eee oe G [Cetreciensesiseensst Bop |==e=s=| op | ap fonse-| pp [eteent [serene ae a "ooo" -o}eTd [VIGo}IOA TYXIS Jo yIprorg
FOL. O)5* 287 |S Se eG ee sass ee eal ara |e rm Ce | Seed EOP lee oleae ie ee ean “~--- aged [v1qoj10A TAXIS Jo yySuy
Qt Sle ss" eesese 6 HOE VASE OES SSCS este iar FOI Giles fairl (aise (iene ho “sould [erqo}10a WQFy Jo [prorg
| | el pai ool fe Ty) f0T Oh Sess) ee ep aL ae ISOS Giese See ea Earn. ns See coal “oper [vaqo}10A TYFy Jo yySuorp
@qo fete: se==52] 9 6 EET eT PL | Ot ROT ele sesss" TELE a OT ea a a oye waqoq1oA YyINOF Fo Typrorg
+25 8 eel [rete (COICICE L IL LL | €6t | BL | PT 4CT ibis | aes Te ae aa essen Wicaeet a a oa ee wre re erases = ognrd [RAqoq1oa TyQINoF Fo YySu0ry
| eget bape SOI SSS fg, Or | €et ral VE | eat as oe lea el EeraT [eae espace 5a eee cme ae os beara oyetd [eIqoj}10.A party Jo Typvoargy
ca ga besitos br I te @L | fer | ter Gye |} Pi OL fc te Soe Gee eater aoe = 5 eee Nita “" "ss ogerd [erqoj1os paryy Jo yySuory
aT Fos )|23325>|-86 OL Soo SPT OL | @L ial Uilebe eae Glew hea 7 vie so aa Bia tn Pee ee & oye [vAqo}10A PuoDdeS Jo YAprorg
cl tpGlsuaeea lS (0) (ae ELT Gyn |} Gir 4GL VJ Soca spel sees Rak ae) gee ae RR ee oye [eIqo410A puodes Fo YySu0'Ty
11 yagi TOSSES RT SER Or 6 OORCr ho oo OL | IL ae CE IPE Sa Sn: FO] ks AVES SESH ea a a ar a a> oyeTd [VIGo}IOA gsay Jo Ty pvorg
61 GY Sac OE TO leet oe se S leeeimicie TS: | 02 & VG | Serasetee: || Be Offa lees: omer a= Saris woes nese sess ogerd [eaqoq10A 4ys1y Jo yySuory
: oovdvivo oy Jo sojvid oy4 Fo sjuomomsvoyy
9¢ QL [rtctttfec eee: 2S CSE OSS SAISIIORE Hel] oye e aiocr ee [ig (Peecoo|sSoqceiee ococl|cCSSee Gobo S0Re Ee soporpoed [vU1099s Jo 4u0}xXo 4 pur oI0\F
L 7 Gee Eee seeees|-s ees Binnie) 9 secccs|eeeeee|seeeee[ eee. fs eyolnle) fain carton losis cicioleis sisisinis (Sisto ee ~T veo™=> To}0U [vuIysygod yo 1y4doq
at Gee eee @remmcsrcees| ge | op Nesseo- QT |-2cc2s|ros-=- Scorer os Sei. pepo ses aera pre gets “Yo}OU [VULO4Sys0d Fo TADIAA
ge Cea Zecca > Soe eiicin ein | siueie S|) SQ Oe) Ns) essere GSE tei rslee seis | Seis RUS eas a oe ae a OAOOIS TUUIOYSIYCIX IOMoJUe JO TIPIAA
6° 9g |tt--: GE [ttre freee 29 09: 9 \==-==- @ay |[]9o0SCb! [Anessa |scocnn CASS Poo aAn ricco Pines heels OAOOIS [VIOULOJ IOLIOZUL 4 TAPIA,
ra gt |r-t77: se ceee| ss eee-|------|------ Gp ler |o-=-- Gp jezeces SES OSS 1/5005) 9000 Sonic SS Se ea ae ~---=-qied youq 4v worseid Jo yySuoryz
09 8B og FOSS IH ear) PK kee NSS “| 09 *S Cite | enema (aan oie, Saeco res eee OA00IS [erouny-qsod 48 TAPIA
as roe 9% OSS eer Seloses: rg CGe es 09 Es rs 0s Sito tise ek ike $2 eine cS eas 8 oIngns [VuLeystdo-jsod yv [PIAA
> ESS, Fy; ra op ee ste se “| £2 PB | TZ 0% TZ Groalkes ues Gia eae aaa ae pea ho o"TOTBOUNA, LOMOFUV FO TIPIAA
ze eT Pea 0g |v seeeee]------ Gaul ltcouml asa = OF |crrt oltre oe seccee fore sdsisisisicie sis Mails ipsiniani-detcicicine qued or0y 4v uoWserd Jo yySuery
a) ae OF |trrt-- see--+|----- +|++---- OG) life. [=== >: Aig. jasc oca|jecoos t|eeee- gl OSoraaeoe Pigigists Finishes ctetcshs TOIUN [VIngns 07 ose Jo yyprorg
O2T Gy SSS SES ROR O50 ODS Ric SSOCG (Sonics OH CaS | key ee esse OCTe paisa we tese| teens Ree cc Si es ie aye > peg oe “““9ulT UVIpeUt UL ToIse[d Jo yySuery
OBL |r ot7|=22- << [ero -- Pas ae | eee | nes mien Wop em cea (RAL JO oe2e|92cs5|55 occal|oonace safes velaicin seis = *--- OUIT JILSIvIys v UL ooVdeaeD jo [4 prog
AA AEA eR cooc Ae Socal aaieos o|-- eee] eee ---] se ----]eoe. ee}. Bape sine aie qaqa na 2== 299990] so Dono|/Saco 9000 CoSoCO DoSo00 G005°r Our] FYS1eIys v UL oovdvawo Jo YISuaT
GET |roccee fee cree |e - eee |----- -|------|----- s|sees--| gop [--e-e- Ber [ror vereee|-- soeo|[oo5000 soos oe re Beiisicer aisle OAINO OY} UL eoVduae. Jo TI prog
s-----)-----./---.- i eee (emeeceaal fio oun ade nals We oon em eicr sao ea psoeia| era cem eras pire =i - 5 <5, no OTT. UL ooBdErEo JO YISUOr,
“SOUNT | SOUT) “SAULT | 8OUYT | “SaULT | soUrT | sauyy | soury |saurz | sourz | sourz | sour | sawy | sour
|-
“FI | ‘SE: “Al “li ‘OT 6 8 7 9 "Gg v S % ‘T pucuuoeds

e

151

“SOUT

PL

“SOUT

“EL

ype QU eal fe gS ey all pene eee al Gy 66 es 0G eee eee es | ee eect oe ODLOG LOTONME ato NETO [eusysrydix Jo qApeorg
edate or hee cane pe ed cae 0g GEOG Pt |meee ta bo Cie esr aimee | ebrge ce| lcc gag eet ees A chet lick Jop10q tout 4v oyvtd [euxoysmdrx jo q}suery
ae | eee Wee eal Rete ah oe eek Vv 68 Swe | APO VNU deeined| ca a aeulamem etic, en Se OTD DION NB Ole TO: [eusoysodky jo qi peorg
eae : Calelasie se geen a GP 8s | IP Oe i Oe eae eas) LO PIOT TOMO AE orm mraisodAr, 10 yysuory
ae a cecal | eee iene |e Somer OP: IV ae ber (2) (ke Re arate | tamaoaac CAS ST | SA eae ae Maeve ed “--"-9Tpplut 9ev oyvyd [vureysoXy Jo Yypvorg,
or aS So CAs || fe Soe Re 66 LG essa [eppaclle wen 7 2 Sia Smee cae = a a a “-""-Jopilog Jeuur ye oyv)d [eureysoky Fo Yyouory
Se Gkele eee (ORE | SL, ey ae Il | ST 0 | ert Sea leads ci toprog Lor194sod qv oyeid yeusoysido Jo Wyprorg
eee Deal So aaa Il Me eee pT Sl er Ce ie Fo) ea | le ae ai ce or hoes ai Jopiog JomUr 4v oyvyid euseyside Jo qySueT
OL ASU Pe SS ee ES Ip ice | o 0& | 9% DoGIe al eo ee ae sane a ogni d [eureysozuo Jo YIpLorg
HOR alae wise. 6 ee eG ON ele eral tree ike (Of 2° SRR | masey te ine de Bee lea 9070 [& [vUuIE\sojUO Jo YASuOT
: moaysvyd ory Jo soyvyd ony Jo SJTOULOINSvOTT
pare ess | eae sie | ss siete |ieats a Lamy oS BC | Ses itce Sahel nie Glee. Hae eae |e aie algae Geena oe Se ei ees o7eld [vuLsIroL 43004 Jo Yyprorg
eos eee es Presence theo Nie mmerle iG, )e- leeeee (es arte gy ee geal RTRs r= one eMiotee tue) Jo YIN
ead taioe| | coos elie eae ean SMa E | eek ge sn eter emake ele Gil bese ong [ieee aan aie gee ie ule Gee ees 15 OIC Ce oneie nt Tq.910 jo [prog
eee eee oe A ey ee ed aa PEERS ea Sa at iia Sere ese nl pO (ogest (oun whe Lato OA|
SATS a pere we peso ake wate |e es [Sees Lor een [eee een esl ie) ee eens me DUCK Out ole da eololrun Ren oO mipeond
cig cep saa aaa ipa g eels ea tiene a (een LI a IS ae ei vCaTG | Nol COMM EINE fen bsptietens raph-qte) 10) apkslotaya |
paces Ole pena eS Ses niscae a eos oT ea ie ie been | net ee eee tegen eee SUC OUIUl Eoin Oamentanr un priyy Jo yAproig
Sesie Soe een eee ee ei Gees c CIs Wee SOIT lessee eer Ie cee Meee a) 09) q PUCMany Os Olid (emigieun pag) TO manary
SOE aya a Sagi cs (cia ae 0@ | OT rea Di eae gs allie son ral | ae a na "7 -""="="- 9opo Jeqno qv o7eTd jeusiem qs Jo yprog
Sine (Re RES | OU aati) aia a1 CB (SIE RS SOS SOE SUCHE TANI Me NMAUTOGESNGTE 10) (of MOROAIA |
Bags PES SSE ESC ERS Ene poae eer alErL GIR Ehtle: pce eiSet Gllimice oleae roo eo se eee Aywusszxe eyed [eyso9 parqy Jo yyprorg
ole Cee CU eas gc SI | ST PAA UE eR Ut 3 igs et eh | ar el ae “Ay[euseyzur oyeyd [eysoo paryy Jo yypLorg
Sy eee ie | ae ohne ay eal ee nn Eee iole az 0S OGRA ce sansa ere ces gc sia leet cere ein tg So meee “----="=-oqeid [24800 paiqy Fo qySueT
dia reo BOP ESTP eal I era RI Vie sents Oh oe cleesjiuletue e08) 00 oc tees eATIUUIONXO ONyd [Zqs00 pucsos oMmapearcy
ERAS 8 Oe haeeaeleaas. | COT Seo OL UE tse itp otlecees |itit0 0 <2 oe coos A[@udeIUT oneld [eIG00 pudses Jo yapEorgy
HE peeeceea tno aso Gen Ape Ca ae 0s GY a) san |e a tes fp er eee gees eee ee one eAsooumO DSS TOMA elan: ©
ete OT ag eae ae ‘ota LS 86 0§ ros Are Bees egal cay Si ira apt ce = ae ane aren tage a eyvid [vqsoo sayy JO YIpVoarg
Repeal EE hae g) SR eS SRS SEO [Pte lh ave OF ii oe el Nea || 1 a ae 2 | eae ee ea Bo ae ee ae a rig “oer [eqsoo 4sayE Jo qASuOT
ene le ie ae ea in eal OC ECE ce iG oy ies Bares ele etc 6 ieee cannes Gan ee OUT Bt OmUerONr aD EOlg:
Noa jlo teeter fier ec sles ROG Nee rGe Ice cee dG cel sae ea S one aa ae ee ie enon uso oue'y
" :eonderro oq jo soivtd 03 Jo sjucmornsveyy ©
“SIUVT | “SOUT | saUVT | sau] | “soULT | ‘sourT | sauvy | sauvy | sauvy | saw | saw | -sauvy
aD BL iO Is Oe rOe i aca Or NG soleil Sil eG a |i ‘uompoods

52

1

See ,
see ee Pr
ee. ed
= ee c

0&

KG V5 |e 27
Cae ec as
86 él
0 - | OL
cé él
08 ial
se-2--/ 9
ae 1%

Fi Lag ey a
at Sal) AP
igs kel (
eis &&

"SOUT | *saurT

Se ee soe
GG &@
Fee ins
LG. |" oe
Grae Be

"saUVT | saUvT

“él “TL

‘Or 6

Siete
(team = >a
Gre
le eee
SSOSSe i (0s
So ooes 8B
t oF
Open ae as
ear ee es
oes (as
BSBA Xe
ee 18
66 | 66
ee PS
OF Le
OS jh ae
tL $01
G g

“SOUT | *SOUVT

‘8 %

*sOUVT

®

baal:
ere 08
baer ty
Sans eT
a Te
RES oer
& | 8ST
Vor) er
& | oT
Ble|| ea
aeers 13
a re
TE | 92
ee 0s
0g | 28
wv | w
ies ep
Saatsy OL
pala aI
See Oy
sia 0g
gg | 9%
eas ae
G| 9%
ss | og
93 | 98
ze | og
Ip | 9¢
cg | og
or | 9
ie Wg

“SOUT | soUvT

ees ees -

BES A6e
Sea || OS
pat oat 08
ba cet || 0G

soos seas sesese- <T]/VUIO}XO OINOS [VULSAVUT TMOAITO Jo YIpvorg
weessegese sw mn==- KT[VUIO}XO OFNOS [VUTSIVUT TAMOASTO Jo TYSUET
soos seweesssa----KTTVUIOJXO ONS [LULGIVUL TYYSIO Jo [por
peas * AT[VU10JXO OYNdS [eULdIvM YIYS1o Jo y4ySueryT
(wos ewens ses-s=* <TTBUIO}XO OFNOS [VULSIVUL YIXIS Jo yIprorg
Pesan sense *-- AT[VUIOFXO OFNOS [RULSAIVUT TAXIS Jo YYSueT
Pipes mires oes AT[VU109}Xo OYNOS [LUISIVUL puodeSs Fo TAproIg
AT[VUIOFXO OJOS [RULGIVUE POdES Fo YASUErT
phaeaecaetehricisiais = sis /cisisis A][VUISZXO ONOS [LUISIVUT ysIY Jo Typvorg
Ber PSE “-->7-->*-AT[VUIOFXO O9NOS [LUTSIvUT Ysa Jo T4SuoT
repre isesriapeisar ees ai5% O[PPIM 4V o9Nos [Vys0o0 YAN0F Jo YApverg
pigs OPP 4V O4noS TLISOD YAIMOF Fo YASUE]
O[PPIUL 4v o4nos [eASOd pIIqy Jo YYpvoagy
pe vane ped Se * “O[PpIUL 4B O4NdS [e4S00 paryy Jo YYSuorT
poo "Tous tems ss "==" OTPPLUL 4B O¥NOS [24809 PUOdES Jo YI pvoIg
pe OO eer OPP 4B OINoS [vIS00 puodes Fo YASUO]
I Tooes esas ssse=="--OTPPIUL 4B OFNOS [L4Soo 4suTy Jo YY proagq
Pgs seis. woes seoss* "=" -9TppIUL 7B O4nos [e4S00 Ysay Jo YSU]
eqjnos [eokd Jo TQpeoig
cesar nee Susy 2 $096 os eases == OOS [BSAC FO TIcUSTy,
SHES STS Tere esecessossssm=--- anos [RIQO}IOA TIL JO Wpvoag
as ite cone Boos enon sooo ss==5° OINOS [VIC OJIOA TIF JO Youery
ee oe aaa ONS [VAIQoIIOA TIINOF Fo TApvoag
""7 "===" -99NDS [VIQO}IOA TIINOF Jo YYSuST
FoR tPisueeioRicienssios "* -OINdS [LAC OJIOA PILyY FO YYpLorg
ONS [VAGCOJIOA PAT Jo YQSuer]T
sae ecce ce ONS [VIGH}IOA PWOdES Jo YApLoIg
SRE OC Boa CU ae ao o ae a gciao ONS [VAGOJIOA PODS Jo 74SU07T
ee ee RE ae arise “77> OINOS [VIGOJ.AIOA YSIE Jo YYpLoIg
Sisieistasis pusiel faasielcola Nels cba clot “=->=" QNOS [BIG OJIOA Ysa FO TSU]
“----"-9]nos [BYNUM Jo YI pvorgq
rishistnealeicts ognos [eyonu Jo YASUuerT
> oovdvavo oy} JO Sojnos oY} Fo sjueMornsvopy

‘uetmmloedg

WOWROTUNTAMIOS SIU} UL poqitosap “oul, 4SAY ot[} AOF ‘av sIoY}O oT, “waphneT “sy 01 G ‘ON pur Sisaunay ‘Wy 0} F ‘ON
* SRUDYUOSUANIIY “FT 0} POLaJOI O8O} “E “% SON Ssesuasuruohm 7 04 pordoyar AT[LULSIIO yey} SVX T ‘ON UOUMIOAdS oY,

153

£9 OIL QO He eer oo OTT OT | GI 1 6L | 61 LT ST

“"""""=-TopIOG 1O110}UL 4B Soynos [eIOMIET Jo YA pvorg,

TG «| anes RS “So tke oe ee OOO CORD OE IC Ayjeurequr seqynos [e1ouey; Jo yyoueryT
Gea sot lle eeael geal | een peRC Ty VV GE DIES cassie Gh ule >| PSes oo eee STs a te ores SG) oh onan eth (elthatays [eulmMopqe Jo yAprorg
$6 Se a S| eee oe eR (ae cE OSs ess SG |e wee |P oe cope eee ae as eS A][VUIEZUT soqnos [vuIMOpYr Jo yyouery
£3) fecal ee ate EY cel ero BE eee ee Se Daca aes arate Spams i “""-*-9[pplt 48 soqnos [e10j00d Fo yyprorg
6 €1 Ge ise Ses ees ee, (Gal Came ass imate ae ee Sie Wome ale To coos secs eesecesso=>-- AT[VUIEZUT Soynos [vxto0jo0d zo yQSuory
él 91 Ale li Gace | opine | alli Gime | REG. aH mele OSs ieee ea [eames Sal ess ae "TTT sss="" JepIog Youd 4v soynos [vsomny Jo yypeorgq
G OL (Split ee geal lees Sal Al Cyt To SSaea eepPca er (53) taal a2 GRASS E"5 Sng Umea cong ees So aa Sy 2 ~--- A][VUTOLUT soqnos [eIeUUNY Jo WySuery
9 fk Sper ee se Sey Glew stSp “|e GT Slee nel pe peal ail Se a ee OTE UP Senos wens JO WYprorg

~---opIog IOUUI 9v seqnds vps Fo TySueT

: : uoayseyd oY} JO Seqnos oT} Fo sjuoMoInsvazy
“SOUYT |*8IUNT | "SAUNT | “SOUT | “SOUYT | ‘sauvT | sawyy |*saur'T | ‘saury | sour | saur7 | soury | sour

Rel! “6L ‘TL ‘OL 6 8 ‘h ‘9 ‘G a i G IE ‘uounledg

204

154

BAPTEMYS.

A peculiar and interesting genus of extinct emydiform turtles, apparently
intermediate in its characters to the existing American genera Dermatemys
and Staurotypus, is founded on remains in the Bridger Tertiary formation of
Wyoming.

In shape and constitution, the shell of Baptemys (Plate XII) approaches
most nearly that of Dermatemys, more especially the carapace, while the
sternum partakes of the character of that of Staurotypus.

The carapace is oval in outline, apparently not wider behind than in front, _
and with the prominence or convexity about equal to half its breadth. The
convexity is nearly uniform fore and aft, and laterally to the flexure of the
marginal plates. The anterior border is barely everted and is thick and
rounded. The imperfection of the fossils prevents a determination whether
the posterior border departed from the general convexity of the back of the
shell. The surface formed by the first and second marginal plates is feebly
depressed.

A median carina or thick rounded ridge starts upon the sixth vertebral
plate and extends backward.

Eleven vertebral plates enter into the constitution of the carapace. Those
anteriorly are proportionately much longer than in emydes. They also appear
proportionately of greater extent than in Dermatemys.

The first vertebral plate is oblong, somewhat narrowed behind, and with
the sides convex. Those to the sixth inclusive are hexagonal coffin-shaped.
From the fifth they rapidly decrease in length.to the eighth inclusive, and
then increase again to the last. The seventh is more uniformly hexagonal
than the others. The ninth is quadrate and wider than long. The tenth is
- quadrate, widest behind, with the lateral borders convex and the back border
concave.

The costal plates are like those of Dermatemys, and as in this widen out-
wardly more than in ordinary emydes in accordance with the greater convexity
of the carapace.

The nuchal plate and marginal bones, so far as preserved, appear to be
nearly as in Dermatemys.

The scute impressions of the carapace, as in the latter, are not defined by
such deep grooves as are usually observed in emydes.

HSS

The vertebral scute impressions have the same form and general propor-
tions as in Dermatemys. ‘The first is wide, urn-like in outline, and is broader
than long. The succeeding three are quadrate, with the length greatly ex-
ceeding the breadth, and with the usual lateral brace-like or double-sigmoid
borders. The last impression narrows for a short distance and then diverges
in the usual manner.

The costal scute impressions resemble those of emydes and extend further
upon the marginal bones than in Dermatemys, nearly reaching the middle of
their outer face at the sides of the carapace, as far back as they are preserved
in the fossils, as well as in front.

The position of the nuchal-scute is not preserved in the fossils, but the
part immediately contiguous in one of them indicates that it had about the
same proportions as in Dermatemys.

The marginal scute impressions about occupied the lower two-thirds of
the outer aspect of the marginal plates. The line intervening to the first
two marginal scutes is continuous with that between the first vertebral and
the succeeding costal scute.

Considering the striking resemblance of the carapace of Baptemys to that
of Dermatemys, it is not a little surprising to observe so much difference in
the plastron, though this also is nearly alike in the scute impressions.

Compared with that of Dermatemys, the plastron is remarkably small,
leaving proportionately much larger spaces in advance and behind the bridges
for the movements of the animal. As before intimated, it is intermediate in
character to that of the last-named genus and that of Staurotypus. The
pedicles are intermediate in extent to what they are in the two genera just
mentioned. The fore part of the plastron has nearly the same shape as in
Dermatemys, but is widely emarginate at the extremity, and it is thick
and rounded at the border instead of being acute as usual in emydes. The
back part of the plastron is narrower than in Dermatemys, but less so than
in Staurotypus. It terminates in a rounded extremity as seen in Fig. 2,
Plate XII. - In Derthatemys, it ends in a wide notch; in Staurotypus, in a
point.

The entosternal bone is proportionately as large as in Dermatemys, and has
nearly the same form. The same may be said to be the case with the epister-
nals, (Fig. 6, Plate XV,) except that their anterior border is more concave.

156

The hyosternals and hyposternals have nearly the same extent. Their
intervening suture crosses the sternum near the middle of the pedicles.

Dr. Gray, who established the genus Dermatemys, represents the South
American species D. Mawiti, with a pair of gular scutes. D. Berardii, of
Mexico, is represented by Dumeril as possessing a single symmetrical gular
scute, and this also is the case in two shells from Balize River, Yucatan, and
‘Tabasco, Mexico, described by Professor Cope as pertaining to another species
which he has named D. abnormis. 7

In Baptemys there is no trace of separation of gular scutes from the
humeral scutes as indicated in Fig. 6, Plate XV. The grooves defining the
latter from the pectoral scutes occupy nearly the same position as in Derma-
temys, crossing nearly through the middle of the entosternal plate.

In Emys the gular and humeral scutes fold deeply upon the upper surface
of the sternum, but in Baptemys, as is also the case in Dermatemys, the cor-
responding scutes fold only to the upper edge of the rounded border of the
sternum.

The intervening grooves of the pectoral, abdominal, femoral, and caudal
scutes nearly equally subdivide the sternum of Baptemys.

The pectoral and abdominal scutes extend upon the sternal pedicles, and
are there separated from the marginal scutes by large intervening scutes, as
in the sea-turtles and in Dermatemys. In the same position in Dermatemys
abnormis there are four of these scutes. In one of the specimens I have had
the opportunity of seeing there are four of these scutes on one side and three
on the other; but in this case it appears evident that the reduction is not the
usual condition in the species.

There are three scutes on the sternal bridge of Baptemys which succes-
sively increase in size. The first or axillary scute joins the fourth and fifth
marginal scutes and the pectoral scute. The middle or submarginal scute
is hexagonal, widest transversely, and it joins the fifth and sixth marginal
scutes and the pectoral and abdominal scutes. The third or inguinal scute,
nearly twice the extent of that in advance, is also hexagonal. It extends
across the hyposternal upon the hyosternal plate, and joins the sixth and
seventh marginal scutes and the abdominal scute, an outward prolongation
of which to the inguinal notch separates it from the femoral scute.

The axillary fossa reaches as far back as the posterior third of the fourth

157

marginal bone; the inguinal fossa extends forward nearly on a line with the
posterior border of the sixth marginal bone.

The interior of the fossils being occupied by the rocky matrix, all the
internal anatomical details are concealed from view.

Baptemys in the relatively smaller size of the plastron to the carapace, and
in the presence of submarginal scutes to the sternal bridges, is more nearly
related to the marine turtles than the genus Emys.

Baptemys appears also to have been nearly related with the equally ancient
and extinct genus Pleurosternon, of the English Tertiary formation. In
this the vertebral scute areas of the carapace are remarkable for their breadth,
which considerably exceeds the length, whereas in Baptemys the intermediate
vertebral scute areas are much longer than broad. The plastron in Pleuro-
sternon is intermediate in its proportions to that of Emys and Baptemys, and
has an additional pair of bones entering into its composition which do not
exist in the latter genera. In Pleurosternon a pair of integular scutes inter-
vene to the gular scutes; in Baptemys there appears to be no distinction of
- gular scutes from humeral scutes. In Pleurosternon, as in Baptemys, large
accessory or submarginal scutes intervene to the comparatively large axillary
and inguinal scutes.

BaPrEMYs WYOMINGENSIS.

The species thus named, as well as the genus, was first characterized from
a beautiful specimen of the turtle-shell, discovered by Mr. O. C. Smith, of
Leverett, Massachusetts, while engaged in the service of the Union Pacific
Railroad Company, near Fort Bridger, Wyoming Territory. The specimen
was loaned to Professor Hayden, by whom it was sent to the writer for exam-
ination. It is represented in Plate XII, one-third the natural size.

The specimen consists of a shell which nearly retains its original form, but
has lost thé front marginal plates on one side, all those behind, most of those
of the left, and the front part of the plastron. It is black, as is frequently
the case with the fossils from the same locality; and it is filled in the in-
terior with a gray sandstone mingled with coarse pebbles of indurated bluish
clay.

In its perfect condition the shell has measured about a foot and a half in
length, and in breadth about a foot. Following the curvature of the carapace

158

fore and aft, it has measured about 20 inches in length, aud the transverse
arch from a level has been nearly as great.

The length of the plastron has been about 114 inches ; its breadth from
its sutural junction with the carapace is 9 inches. :

The sides of the plastron slope inwardly to a moderate degree. The pedi-
cles are nearly on a level with the rest of the plastron, but are somewhat
prominent in front and slope backward, and are concave approaching the
inguinal fosse. The rise of the shell appears mainly to commence in the
marginal bones from the sternal pedicles; to what degree is uncertain, as
this part of the fossil is somewhat crushed inwardly. The rise is greater
anteriorly, and gradually appears to subside behind.

The fore and aft extent of the pedicles is 44 inches. The length of the
anterior extension of the plastron has been about 34 inches; its breadth at
the bottom of the axillary fossze is 54 inches. The length of the posterior
extension of the plastron is a little more than 34 inches, and its width at the
bottom of the inguinal fossz nearly 43 inches.

The marginal bones appear more abruptly bent to join the sternal bridge
than in Dermatemys, but the difference is partially due to the crushing
inward of the under part of the shell in the fossil.

A second specimen of the shell of Baptemys wyomingensis was subse-
quently discovered during Professor Hayden’s exploration of 1870 at Church
Buttes, Wyoming.. The shell is of a different color, and is filled with and
partially imbedded in a different matrix from the former specimen. The
bones are brown, and the matrix consists of a very hard sandstone. The
specimen, though far less complete than the former, fortunately retains one-
half of the anterior part of the plastron. Most of the carapace is lost or
imbedded in the hard rock. The sternum on one side from its fore extremity
to the commencement of the xiphisternal bone, together with the pedicle and
its characteristic scute impressions, is well preserved. g

The measurements of this second specimen indicate an individual of the
same size as the former. Slight differences existing between corresponding
parts of the two appear to be variations only of an individual character. In
the second specimen the large inguinal scute passes just over the back edge
of the hyosternal plate, while in the former one it extends upon it for half
an inch.

159

Measurements derived mainly from the more complete specimen are as

follows.
Length. | Breadth.

3 Tines. ~ Lines.
Emer veT DOULA Dlaber i. = 4 itt Mae fate ae Me he woe Soetoro 27 13
Seema VELpCOLal PlabCstaeg aaj coer oe ian mies eats ca oni 22 14
Baitnccdeverteoral plate c22 S026 eerste. bls 2b Sk eee cm Ce rcinwsees 23 14
Hourth, vertebral plate.---.-..\. -<-s+ ..---- =< PADRE. He wha lags: 22 14
[Surin sperensl one! O22) Wore See eine eeeeee Seo einem Sor ee ine Acree 22 15
Sema MMOGUC DLAI DUAUE) crerraee i cielo omic an al Sen 4 Swe ele wel aie pare wwe 17 16
SemenimeVerkeDlale PIALC 24 too cielo nia cscs ceeds ewes aen asses 10 ey
POM VeGLODLAL WATE eens canned nes onie ease hea onan: 7 £2
MMV EEbeMEA PIAL. 2-2... 2---20 2 somes cbmesess wnan re es=ss-m- 9 14
Hemth vertebral plate.......--.-.-----2--- 22-2 eens eee tee Pees 16

Width Width

Pee internally. | externally.

Lines. Lines. Tines.
LS GOR tEI OIE Cee Eee ee ea oe 45 26 37
RPE OS TAM OLALC torat~ =i .n) els clan ee cle nia alcholic ise olen s 60 24 26
PIMMIRMB CO SUL PIAL co ae es een ee nee eee eee 70 24 27
Monctm costal plate... 6.2.2 cee eee eee Fit sites Bist 2 eb. 73 22 o4
JEN) CCISTEN O11 le 69 20 30
Sunn COR) CC th ee a a are ea 60 aly 292
BemembhCOstal Plate... 5.20 2-20. sence eee ee ee eee ete 47 15 20

The nuchal plate fore and aft has been about 2%-inches; its breadth about
an inch greater.

The marginal bones, so far as preserved, appear to have nearly the propor-
tions and aspects as in Dermatemys. Their vertical measurement is about
2 inches, and their width about the same.

~The measurements of the scute impressions are as follows:

*

Length. Breadth.

Lines. Lines.
insti yertepral SCUve IMpPRESSIOM ~.=...-..-5- 2-2-2202 62. ee oe 39 52
Necond vertebral’ Scute IMpPression.......-..- 2.2... 22sec ee ene oe ee 50 30
Gihirdeyertebralescutie WMpreSssion... 2.2... 252. sss..e sees eet ees 43 33
Fourth vertebral scute impression .......-.--..-2.-----.--.00-5 38 32
Msi COStal SCULE at MMOGGle soo. 22s 2. le ee eee ewe ee 54 56
Mecond costal scuterat middle)... sl. kee eet eh ee eee 74 46
Eds costalseute at middlens 202.20. e eee See eae eee es 70 46

160

The episternals at their inner border measure 1 inch in length; at their
posterior extremity 10 lines.

The entosternal bone is 25 inches fore and aft, and 2# inches wide.

In the better preserved of the two specimens the plastron presents the
irregularity of having the left hyposternal and xiphisternal near half an inch
more produced forward than upon the right side, as seen in Fig. 2, Plate XII.

Measurements of the remaining sternal bones are as follows:

Lines,
Length of right hyosternal internally - 0.522.232 52 7. 220. ste 30
Length of left hyosternal internally......--.-... .2.--.+|-- ===. 7-2 = eee 25
Breadth of hyosternals at middle......-.....- wale @ vb bu nein Jue) aoe ee 58
Length of hyposternals internally .....- 2... 2-2. 25 ee A 34
Breadth of hyposternals atimiddle. 7-2. 2s... i = = -) ei eee ee +. 3s eee 52
Length of right xiphisternal internally ..-..-.....-.--+.---.0-=-----=5— =e 34
Length of left xiphisternal internally .....- -...2..----2-2-6-s2ss) «+2 eee 40
Breadth'of anterior border ¢.. 22. 65 2.< o. ee oes 2a bh 2 beet oe ae) BE

Measurements of the scutes are as follows:

Lines
Length. of gular-humeral scute internally ....-- 2. ---2.-<s-2--2sses— eee eee 28
Breadth of gular-humeral scute posteriorly.......-.....---. Pees Me 5 2 26
Length of pectoral scute internally ......--..-...-- Pi oS aaepeee 18
Breadth of. pectoral seute posteriorly .-...-.-.. -.--<2-- 22 sac. 2 ae aoe 36
Length of abdominal seute internally ..2-.--.-..-...----.-2- -..-2 ere 29
Breadth of abdominal scute posteriorly .....-.--- Jisnbee oitu. ee 28
Length of femoral scuteanternally . 22 ....25 i nee > oe oe i oe 26
Breadth of femoral scute: posteriorly ..... ...---...2:=.---e-----+--- == See 22
Length of caudal scute internally... .22..---2.-.-. 2.2 32 ee eee 27
Axillary scute obliquely from within outward..-..2-222:.5-.+.2.-2ces4--eeeeeeee 32
Axillary scute at posterior border .... 2. < -2.0 05. 226 26s bcecn see 3 ee eee 13
Middle scute of sternal bridge fore and aft ......- ble viGies bss—s6 soe 17
Middle scute of sternal bridge at middle, transversely....-..-..---.---.-------- 25
Inguinal seute fore and aft...-... sjaica bg laveercacla dpe aed Mees ete eee io) ee
Inguinal ‘seute at:anterior border. .-...-.---- 2 2. <2... 52-s2--- == er 13
Inguinal scute at middle between prominent angles.....-..-...-.. Bess. 29

BAENA.

By this name I have distinguished a remarkable genus of turtles, indicated
by remains in the Bridger Tertiary beds. It partook of characters of the
snappers or chelydroids, the terrapins or emydoids, and the sea-turtles or
chelonioids. ‘The specimens upon which the genus is founded consist of shells,
which are mostly so much crushed and distorted as to render it somewhat
uncertain as to their exact original and perfect form. ‘They were apparently
about as prominent as in our snapper, and had nearly the same outline of shape.
The middle of the carapace is not depressed as in the latter, but is somewhat

flattened, and forms a continuous convexity with the sides. The posterior
extremity presents a deep emargination as in the snapper, and on each side is
notched likewise as in the latter.

The plastron of Baena is emydoid in character, and in its degree of develop-
ment in relation with the carapace approaches that of its associate genus Bap-
temys. As in this, large spaces exist between the extremities of the plastron
and carapace, but comparatively of much less extent than in Chelydra. The
pedicles of the plastron are immovably conjoined with the carapace. They
are as wide relatively as in the emydoids, but are much longer. The two
extremities of the plastron are nearly alike in shape, being tongue-like and
feebly emarginate at the end.

The number, arrangement, and general form of the corneous scutes of the
carapace appear to have been the same asin Emysand Chelydra. The plastron
exhibits two pairs of gular scute areas, which, together with the other scute
areas, made seven pairs to the plastron. In addition to these the pedicles
exhibit a row of scute areas between the former and the marginal scute areas

of the carapace, as in the sea-turtle, the snapper, Dermatemys, and Baptemys.
A feature which may be regarded as a character of Baena is the obliteration
of the sutures, and the shell at maturity has the bones so co-ossified that their
original boundaries cannot be traced.

The true ribs or costal arches, connate with the costal plates, are remark-
ably prominent in Baena, and the costal capitula are well developed. In
several specimens, in which portions of the carapace are broken away, the
mass of rock within exhibits deep concave grooves indicating the former
position of the rib-arches.

The sustaining columns of the carapace, springing as processes from the
hyosternal and hyposternal bones of the plastron, are of great comparative
breadth, and subdivide the interior of the shell into three compartments as in
the Batagur, a genus of fresh-water turtles now living in India.

BAENA ARENOSA.

The species thus named was originally founded on a specimen consisting
of a nearly complete turtle-shell discovered at the junction of the Big Sandy
and Green Rivers, Wyoming, during Professor Hayden’s exploration of 1870.
The specimen is represented in Figs. 1, 2, Plate XIII.

The shell, besides appearing to be in some degree crushed downward or

PALES

162

flattened, has lost the fore part and right border of the carapace. ‘The plas-
tron, less injured, has lost its anterior extremity.

The outline of the carapace appears to have been broadly oval; and the
shell was apparently not more elevated than in our common snapper.

All the bones of the carapace and plastron are so intimately co-ossified that
the position of the former sutures cannot be detected. The grooved bound-
aries of the scutal areas are, on the other hand, well marked.

The carapace corresponding with the position of the intermediate vertebral
scutes is flattened and slightly depressed at the middle. It is most prominent
along the lateral boundaries of the vertebral scutes. In the position of the
last of the latter it is most prominent at the middle. No distinct carination
exists, but a feeble and widely interrupted ridge occupies the median line of
the carapace, scarcely noticeable were it not better developed in other speci-~
mens. The sides of the carapace slope evenly outward to the rounded flex-
ure of the lateral marginal plates.

The posterior marginal plates are notched as in the snapper, and are slightly
recurved at the prominent ends. Between the last pair of marginal bones a
wide concave emargination exists, as in Chelydra, but of less depth.

The intermediate vertebral scute tracts are nearly square, and are as broad
as, or a little broader than, long. The lateral grooves have the usual brace
form. ‘The groove between the second and third tracts is convex forward ;
the succeeding one much less saat and that between the fourth and fifth tracts
is much produced forward with a mammiform outline.

The costal scute tracts aremearly like those of Emys and Chelydra. Their
grooves are directed nearly parallel outwardly, except the extreme back and
front ones.

The plastron appears quite flat and nearly on the same level with its pedi-
cles, but this condition is evidently in some degree the result of accidental
pressure from above. ‘The posterior extremity is broad, linguiform, with the
end slightly and concavely emarginate.

The pectoral scute impressions, as in the Chelydra, are larger than any
others of the plastron. They extend outwardly on half the breadth of the
sternal bridges. The anterior groove is directed outwardly on a level with
the bottom of the axillary fossee, and near its end turns abruptly and obliquely
forward to the edge of the latter.

The abdominal scute impressions, shorter than those next in front and

163

behind, extend upon the posterior half of the breadth of the sternal bridges.
Their posterior groove is directed obliquely outward and backward to the
bottom of the inguinal fossee.

The femoral are considerably larger than the costal scute impressions, and
defined from them by a sigmoid groove.

The bridges of the plastron present a row of four large scutal areas inter-
vening between the pectoral and abdominal scute areas internally, and the
marginal-scute areas of the carapace externally. The first and last of these
may be regarded as homologues of the comparatively small axillary and ingui-
nal scute areas of Emydes; the intermediate ones are superadded.

The axillary scute area, partially broken away in the specimen, appears to
have had four borders, of which the anterior formed the outer boundary of
the axilla, and the internal joined the pectoral scute area.

The second submarginal scute area, the smallest of the series, is quadrate,
and internally joins the pectoral scute area. The succeeding submarginal
area, larger than those in advance, is pentagonal, with the two shorter sides
forming a projecting angle joining the pectoral and abdominal areas.

The inguinal scute area, larger than the others, has four borders, of which
the internal joins the abdominal area, and the posterior bounds the greater
part of the bottom of the inguinal space.

The surface of the carapace is somewhat irregular; that of the plastron is
more regularly and minutely roughened or fretted in appearance.

A second nearly complete specimen of a shell of Baena was discovered by
Dr. J. Van A. Carter at Church Buttes, on Black’s Fork of Green River, three
miles north of Fort Bridger, and was obligingly sent to the writer as a gift.
The shell, like the former one, is considerably crushed, so as to render an
exact determination of its original form uncertain. It approximated the other
specimen both in shape and size, and, like it, has all the bones so completely
co-ossified that their limits are obliterated.

This second specimen presents several differences from the former one,
which led to its having been considered as pertaining to another species, to
which the name of B. affinis was.given. Additional specimens since obtained
and exhibiting other variations have led to viewing all of them as belonging
to a single species.

The carapace measures 13 inches in length following the curvature. Its
anterior portion, preserved in the specimen on one side, has a rather obtuse

border, and is not recurved. In front it is prominent, as far as seen in the

164

specimen, corresponding with the position of what appears to be the outer
portion of the nuchal scute area. The latter apparently is of great width, at
least an inch at its conjunction with the first vertebral scute area.

The latter and the last of the series are prominent in the median line, where
they form athick, rounded ridge. A low interrupted ridge extends along the
median line of the carapace, which is barely evident in the first-described
specimen. ‘The short divisions of the ridge are flanked by equally long fusi-
form: elevations slightly divergent forward. In addition, the carapace is
rather irregularly prominent along the position of the lateral grooves of the
vertebral scute areas. The intermediate vertebral scute areas are proportion-
ately narrower than in the first specimen. ‘The second and third are slightly
longer than wide; the fourth a little wider than long; and the first and last
in width considerably exceed the length.

The plastren is preserved nearly complete, and is iéprenpteds in Fig. 3,
Plate XIII. It appears as if originally it had been less flat than in the former
specimen, as, independently of fractures, it turns up more at the extremities
as well as at the bridges. |

The anterior extremity, which is lost in the former specimen, affords an
opportunity of completing our knowledge of the plastron. It is shorter and
narrower than the posterior extremity, but is nearly like it in shape. The free
border-is obtusely rounded, and is slightly more thickened and prominent at the
divisions produced by the scute impressions. These do not mark the upper sur-
face as in the Emyde. The lower surface exhibits one of the most remarkable
peculiarities of the genus, which is the possession of two pairs of gular scutes.

The first pair of gular scutes are coniparatively small, and are defined poste-
riorly, in the usual manner, by oblique grooves diverging at an angle of 45°.

The second pair of gular scute impressions escaped my notice until I had
seen several additional specimens. As this did not occur until after the draw-
ing of Fig. 8 was made, they are not there represented. They are seen in
Fig. 1, Plate XV, which was subsequently and more accurately drawn from
the same specimen. They are rather larger than the first pair, and are
defined posteriorly by a serpentine groove directed outwardly nearly from the
same point as the grooves in advance.

The remaining scutc areas of the plastron are nearly like those of the pre-
ceding specimen, except those covering the pedicles.

Only three scutes covered the latter in the second specimen, the one cor-

responding with the first submarginal scute area of the first specimen being

165

deficient. In consequence of its absence, a modification of the outlines of the
contiguous ones resulted. The posterior groove of the axillary scute, and the
anterior groove of the area corresponding with the secoad submarginal scute
in the first specimen, instead of being transverse are oblique and join each
other at an angle externally. The posterior two scutal areas also differ from
those of the first specimen in being separated by a groove directed obliquely
outward and backward instead of nearly transversely.

The surface of the plastron exhibits the same minutely fretted appearance
as in the former specimen.

In the perfect condition the two specimens of Baena which have been de-
scribed differed but little in size. The length of the carapace in a straight line
has approximated 13 inches, the breadth 9 or 10 inches. The length of the plas-
tron is 11 inches; its breadth to its conjunction with the carapace about 8 inches.

A third and less perfect specimen of the shell of Baena arenosa, consisting
of the central portion of the carapace and nearly the corresponding portion
with the anterior extremity of the plastron, was found by Dr. Carter on
Henry’s Fork of Green River, and presented by him to the Academy of
Natural Sciences.

This specimen had about the same size as the previous ones, and like them
has all the bones completely co-ossified. The median ridge of the carapace is
more distinct than in the other specimens, and its divisions appear more or
less distinctly to mark the position of the vertebral plates, while the lateral
diverging prominences also appear to mark the sides of these plates.

The intermediate vertebral scute areas are intermediate in proportions to
those of the former specimens.

The surface of the plastron is smooth and exhibits no trace of the minutely
fretted condition observed in the former specimens. The grooves defining
the sternal scute impressions, the median groove as well the more transverse
ones, are less regular in their course than in the other specimens.

The anterior extremity of the plastron, represented in Fig. 2, Plate XV, is
flat, and exhibits the second pair of gular scute areas larger than in the former
specimen in which they exist, while their more tortuous back groove starts
from the median groove a half inch behind that in front. The rounded bor-

der is more prominent in the position of the gular scute impressions than in
the former specimen.

A small part of the sternal bridges retained in the specimen shows a por-

166

tion of the second submarginal scute area with an internal projecting angle
intermediate in extent to that of the former specimens. On one side, also, a
small portion of the first submarginal area is retained, and this appears to
indicate that it was nearly of the size and shape of that in the first-described
specimen of Baena.

Comparative measurements of the three described specimens of Baena

arenosa are as follows:

Lines. | Lines. Lines.

Length of first vertebral scute at middle .......2..---.-----2---|..- MP
Breadth ot first vertebraliscmterim mold Cle ees see eee ee ee =| eee 36, | eeeee
Length of second vertebral scute at middle......... =e pe eer 36 35 35
Breadth of second vertebral scute at middle... ....-...-.---..-- 36 30 32
Length of third vertebral:seutevat middle ---.4.-...-..-s-..--., 35 L 35 34
Breadth of third vertebral scute at middle: ......--....-..-.-.-. 37 bl 32
Length of fourth vertebral scute at middle ....-......--..-..... 29 28. “Eee
Breadth of fourth vertebral scute at middle ........---...-..--- 37 30 33
Length of fifth vertebral scute at middle.......--...-.------.-. 32 ps in eee
Breadth of fifth vertebral scute at middle -........-...-.--.--.. 48 AQ” 52 ae
Width of first costal scute internally ...-... Baia. ee ee ee eas oS ic b47 |e
Width of second costal scute internally ............-....---.--- 37 36 38
Width of third costal scute intermallly>—- 22 -c2 2. acc ee ee 32° 30 30
Width of fourth costal scute internally . - - -- eS be ee Se ee eee rat 170 See
Length of anterior prolongation of the plastron.........-.-..---|...... 35 37
Breadth at base of anterior prolongation of the plastron...-.-..--. 46 41
Length of posterior prolongation of the plastron .-.....----..--- 48 487" | eee
Breadth at base of posterior prolongation of the plastron........ 50 52 52
Breadth: of-pedicles/of£ plastron22- 54 23 ee aere epee ee eee ee ey 62 58 56
Length approximately of pedicles of plastron.......--.---.-..--. 26 24 24
Length of gular scutes internally ----..-2----.-:---.----- a eis HRS 10 16
Breadth of gular scutes at back border .-..--.... “LeU SAT ee | eae | ee 15
Length of humeral scutes internally ......-..-...-. bse Se ae aenee 26 21
Breadth of humeral scutes at back border.............-..-..--- 24. 19 22
Length of pectoral scutes internally ..--.....-.--.-----.- 3, See 32 24. 22
Breadth of pectoral scutes at middle: =.=. ~. 92) 25.42:2< S522 Av. 41 45 50
Breadth of pectoral scutes at back border .........- ee eee coat See 31 31 33
Length of abdominal scutes internally ....-...-.-..- Anos yet Ieee 15 22 20
Breadth of abdominal scutes at middle....................----- Al 38 44
Breadth of abdominal scutes at back border................---- 34 29 28
Tength of femoral scutes internally: - 205) see ee eee eo 28 26 24.
Breadth of femoral scutes at back border ..-..-...-----.------- 21 22 19
Length of caudal scutes internally...-..--...2-+2.---+-- -.-+-- 21 22) ae
Fore and aft diameter of first scute of pedicle.........-......-.]..-..- 184 eee
Fore and aft diameter of second scute of pedicle .--......-...... 16 . |)- 232 .
Fore and aft diameter of third scute of pedicle... ..-....--.-.-- 20 DAO ae oe
Fore and aft diameter of fourth scute of pedicle ....-.........-. 22 20) ee

167

A. fourth specimen referable to Baena arenosa consists of a small portion of
the carapace with a large portion of the plastron, from Henry’s Fork of Green
River, found by Dr. Carter, and presented by him to the Academy of Natural
Sciences of Philadelphia. This exhibits no peculiarity, excepting that the
scutal grooves of the plastron are more irregular in their course than in the
preceding specimens. ‘The median groove of the plastron is especially tor-
tuous, while in the other specimens it is nearly straight. A retained portion
of one of the sternal bridges exhibits evidences that four scutes impressed
them, arranged nearly as in the first-described specimen of Baena. ‘The sur-
face of the plastron is less smooth than in the previous specimen, but it does
not present the fretted appearance of the two former ones.

A fifth specimen, apparently referable to B. arenosa, consists of the anterior
extremity of a plastron, represented in Fig. 3, Plate XV. It was found at
Grizzly Buttes by Dr. Joseph K. Corson, and by him presented to the
Academy of Natural Sciences. It would appear from its size as if it had
belonged to a larger individual than the preceding specimens. It is nearly
flat, or in a trifling degree convex, and is smooth, or without any appearance
of fretting. It exhibits the four gular scute areas of unequal extent.

Another specimen, consisting of the anterior extremity of a plastron, appar-
ently of a young animal of the same species, is represented in Figs. 4, 5,
Plate XV. The specimen was found at the junction of the Big Sandy and
Green Rivers, Wyoming, during Professor Hayden’s exploration of 1870.

In this specimen the sutures are visible, and the contiguous bones defined
The grooves defining the two pairs of gular scutes start all from the same
point, which is near the center of the entosternum. The entosternal bone
viewed below is pyriform, but in the reverse position to that ordinarily
observed in emydes. Viewed above, it resembles that of the snapper,
(Chelydra,) or that of the sea-turtle, (Chelone.) In front it is received
between the episternals; behind, it forms two lateral barbs projecting
obliquely outward between the episternals and the hyosternals, and a long,
median, pointed process extending between the hyosternals. The episternals
posteriorly are angular, and are there received into a notch of the hyosternals.

From the matrix of the first-described specimen of the shell of Baena I
obtained a portion of the pelvis, which presents some anatomical points of

importance.

168

Comparative measurements of the anterior extremity of the plastron, where

this is present in the specimens, are as follows:

First Second Third Fourth | Sixth speci-
specimen. | Specimen. | specimen. | specimen. men, young.
Lines. Lines. Lines. Lines. Lines.
Length of plastron to anterior pectoral
Oi ae Sea cosy on eoteS paso es 5 o4 36 Of . ocean
Breadth of plastron at anterior pectoral
OROOWE), <2 tsa ete ee ae eet atic 44. 36 42 44. louse af
Breadth of plastron at anterior humeral
ONC emo ainaatren oe Sao s a) Moesanconlscua case 28 28 34 20
Breadth of plastron at middle gular
STOOWG: sone i Gusta esine sje eeeeee elas ee 18 18 20 13

The pelvis is more expanded above than in Emys, and in this respect is
more like that of the snapper. The sacrum represented in Fig. 9, Plate
XVI, is intermediate in its proportions to that of the two genera just men-
tioned.

The length of the sacral vertebrae of Baena, independently of the wings or
transverse processes, exceeds the breadth, the proportions in this respect
according more with the condition in the terrapin than in the snapper. The
second sacral vertebra is, however, larger than the first, as in the latter turtle,
and the reverse of what it is in the former. The inferior surface of the
bodies of the sacral vertebree is half cylindroid, depressed at the sides in the
first one, but scarcely so in the second.

The anterior articular surface of the first sacral centrum is moderately
convex; the posterior articular surface of the second centrum is concave. In
Iimys the corresponding surfaces are flat, or nearly so; in Chelydra the ante-
rior one is concave, the posterior convex, with lateral extensions nearly flat.

The proportionate length and robustness of the sacral alae of Baena agree
more nearly with the condition in the snapper than in the terrapin. In Emys
the posterior alee are comparatively feeble appendages, and they join the ends
of the anterior alee by means of a ligament. In Baena the posterior ale are
strong processes, as in the snapper, and likewise, as in this, join the ends of
the alee in advance by suture, but appear not to be prolonged to join the
ilium.

The innominatum of Baena, as represented in Fig. 8, Plate XVI, is propor-

169

tionately of more robust character than in Emys. The ilium in shape is
more like that of this genus than that of the snapper, but is proportionately
of much greater breadth, the wing being of nearly double the expanse.

The expanded extremity of the first sacral wing articulates with the ante-
rior extremity of the crest of the ilium. In Emys it articulates with the
latter midway to the two prominent extremities of the crest.

The acetabulum and commencements of the ischiatic and pubic rami pre-
sent nothing peculiar from the condition observed in the snapper.

Measurements of the pelvic specimens are as follows :

Lines
Length of sacrum beneath the centra.....-...--..----.-.. ae a ee nD 93
Menepivortrst sacral Centrum .......-.-.....--2+-- ee eas een RO AS
meaMiMmOR st SACrAl CENtUM). 0... 2 oe ade ese eee wees ise Serene ea At
enarmon second sacral centrum ....22-... 2... - ene ee een eset be ee 44
Breadth of second sacral centrum ....... Re ne nafs aie et Saya, nr a ore ea Ws S ace 43
Mircea on sacrum ab fish Pair Of ale...-.----..-- 220-2. wee cee fee eet tee 30
Mea pCR UOn DU CNC Tea le cleo Moy 5b Skat theyta aiid Ube Siete ltailayalela le a bce bes colcae «dials 13
Length of second sacral ale ............--..----- ve Be Se Ne ea RE | ae 11
See perme COE OMIM ALU crs cua e = dele ena ses eee Saag ee clte cere weet ete 23
Poem CEeSt Of MNMOMIMAGUUN dor\ iss st he oo 2 oS else uc alee s eee doe wee 18
See eremmneeee di OTE bp eats Ob chad hone 2. StecySin Sloe = ty woe Sm een ood ea eld be 6

EMiea MelnOh ACCLAMULUM) -- 9... ene ewes eee enw ye aees A a DNS CO i Seat oe 94

CHISTERNON.
CHISTERNON UNDATUM.

A large turtle-shell, discovered by Dr. Carter in a chain of buttes a few
miles from Fort Bridger, and presented to the Academy of Natural Sciences |
of Philadelphia, was originally described by me under the name of Baena
undata. A careful examination of the specimen has led me to view it as per-
taining to a different and heretofore undescribed genus.

The specimen represented in Plate XIV, one-half of the diameter of nature,
consists of the intermediate portion of a shell, with the extremities broken
away nearly in the position of the broad columns which spring from the plas-
tron to support the carapace. Though much fractured, it appears to have
been but little so while it lay imbedded in the deposit from which it was
derived, so that it now retains its orginal form. The upper shell is as much
vaulted as in some of the living land-turtles. This form, together with the
thick bone and strong, broad sternal supports, enabled it to sustain the great
weight of superincumbent pressure which has crushed so many of its asso-

22.G

170

ciates. The interior of the shell is occupied by a greenish-gray sandstone,
from which I obtained a pair of sacral vertebre.

The outline of the shell in its perfect condition was ovoid as in ordinary
Emydes; narrower and more elevated in front, wider and more depressed
behind. The fore part and sides of the carapace are uniformly convex, but
the hind part appears to have had the margin somewhat recurved. Over the
position of the vertebral scute areas the surface is flat and even and without
acarina. The plastron is flat, but its bridges turn from their commencement
upward and outward to the border of the carapace, which is elevated 23
inches above the level. The highest part of the shell is nearly 6 inches
above the level of the plastron. The bones of the shell, especially those of
the carapace, appear co-ossified, but not so completely as in Baena arenosa,
for those of the plastron can be distinctly traced.

The intermediate vertebral scute areas have nearly the form and propor-
tions of those of Baena arenosa, and are rather longer than wide. The costal
scutes widened more outwardly than in that turtle, indicating a proportion-
ately greater degree of prominence of the shell.

The lateral marginal scute areas are much like those in Emydes, but the
groove defining them from the costal scute areas exhibits an unusually undu-
lating course, not angular but serpentine or waving.

The number and relative position of the scute areas of the plastron and its
bridges are the same as in Baena, but the median sternal groove defining
them on the two sides is remarkable for its irregular serpentine course,
repeatedly crossing the also somewhat irregular course of the median suture
of the plastron.

The sutures of the plastron being visible, they reveal to us an unexpected
peculiarity, the existence or absence of which cannot be determined in the
shells of Baena arenosa from the total obliteration of the sutures.

The peculiarity in the plastron of Chisternon, to which the genus owes its
name, is the presence of a large triangular bone, added to those which usually
exist in turtles, on each side of the shell. This intercalated or mesosternal
bone commences at the center of the plastron and gradually widens outwardly
to where it conjoins the marginal plates of the carapace at the intermediate
half of the sternal bridge. The four sutures defining the mesosternal plates

from those in front and behind cross the plastron obliquely. A similar bone

Jum

exists in another extinct genus, the Pleurosternon, of the early Tertiary for-
mation of England, but in this it has the shape of a parallelogram:

The sternal bridges of Chisternon present four large scutal areas nearly
resembling those of Baena arenosa. ‘They are not quite symmetrical on the
two sides. |

The axillary scute area is pentagonal, and is the smallest of the series.
The anterior border is oblique, and bounds the axillary notch externally.
Two outer borders form an obtuse angle and join the third and fourth mar-
ginal areas. The inner border joins the pectoral area.

The second submarginal area is second in size of the series. It is longer
than broad, and nearly quadrate, but has its outer angles cut off. The inner

border conjoins the pectoral area; the outer the fourth and fifth marginal
areas. :

The third submarginal area is but little larger than the axillary area. It
joins the pectoral and abdominal areas internally, and-the fifth and sixth
marginal areas externally.

The inguinal area, the largest of the submarginal areas, is obliquely quad-
rate, longer than.broad, and with the outer angles cut off. The posterior
border bounds the inguinal notch; the inner border joins the abdominal area,
and the outer border joins the sixth, seventh, and eighth marginal areas.

The inferior surface of the plastron is comparatively smooth. Striations
cross the sutures, and elsewhere it presents a finely reticulo-vascular appear-
ance.

The fractured condition of the shell affords us an opportunity of seeing
the strong hyosternal and hyposternal columns which aid in sustaining the
carapace. These columns are broad, vertical plates reaching far into the cav-
ity of the shell and dividing it into three compartments, as in the Batagur of
India.

The hyosternal columns are 24 inches wide from their inner concave bor-
der to the axilla. The aperture of the shell between them is a doorway 3
inches wide near the roof and 44 inches near the floor. The hyosternal col-
umns, partially exposed in the specimen, appear to be co-extensive with the
anterior supports.

The breadth of the shell of Chsternon undatum, between the lateral
obtuse borders of the carapace, is 15 inches. ‘The length of the shell, or of
the carapace, in a straight line is estimated to have been about a foot and a

172

half. The length of the plastron is estimated to have been about 14 inches;
its breadth at the root of the posterior extremity is 54 inches; and at the root
of the anterior extremity has been rather less. The sternal bridges measure
7 inches fore and aft, and their length to the outer edge of the carapace is 5
inches.

Other measurements of the shell are as follows:

Inches.

Length of second vertebral scute area, estimated at.....--.-....-.-......-..-- 4}
Breadth of second vertebral scute area <-- 2. 3-2 =e = oe od
Length of third vertebralseute areaya 259] es) ~----2- =a ne le 44
Breadth of third vertebral seutearea.--=-22 = 22-2522-2jees a (Res
Length of fourth: vertebral scute area-----~-- 72-22-52 =n) oe 34
Breadth of fourth vertebral seute area... 2--..--.-- +=. 2 ie 34
Breadth of second costal scute area, internally .:.......-........22.2.2--22- 43
Breadth of second costal seute area, externally ......-7:--...-..22.-- 5) se eee 47
Breadth of third costal scute area, internally ......-.-.- ene te re 3g
Breadthvof third-eostal seute area, externally 252222 = 2. se . df
Height of sixth and seventh marginal scute areas.............-...--..--- ~.- 24
Lene th of hyposternals imternalilys. Jae. -= oa eee ae
Breadth of hyposternals internally .........--- eR ee er 53
Breadth. of hyostennalls...22 28-2 .elotet Aa Sys Pe ee a, 2 53
Breadth of plate intercalated between the hyosternals and hyposternals ....-.. 6
Extent of the same plate at the base externally, fore and aft..............-- . 43
Breadth of groove between pectoral and abdominal areas where it joins the pro-

jecting angle of the third sterno-costal scute areas ........-.....----.--.--- 74
Breadth of plastron at anterior suture of xiphisternals .-..............__- 1). ages
Breadth of pectoral scutes to sterno-costal scutes.........--....------ -- 4 and 43 °
LLength-of abdominal seute intermally > 22252)... 22-2520 62- 5 eeee eee 3
heneth oftemoral scuteumternallly eee. sess ele oe es ee 33
Asallary scute area, length atimiddle. 212-72) -se 9e-> 4 - =e: | 13
Axillary sente“area, breadth at middie. = 5: 22 a= 2 ee 24
Virst submarginal scute area, length at middle .......... ....- aes: S . - - 25
First submarginal scute area, breadth at middle..............-.......... 24
Second submarginal scute area, length at middle .....-...-...-..-..-.---... 2
Second submarginal scute area, breadth at middle..... ................. ... 23
Inguinal scute area, length at middle.......--...... if) Menrans Sin Soe 23
Inguimal seutejarea,jbreadithy atomic ese =e nr a 24

The sacral vertebree, represented in Figs. 11, 12, Plate XIX, are of pro-
portionately greater length than in Baena. ‘The first one is nearly as long as
it is broad; and the second is half as long again as the former, and is equal
in this respect to its breadth.

The anterior articulation of the first sacral centrum forms a decided cup-
like depression, and not merely a transverse concavity like that in the snap-

per. The second sacral centrum is prolonged to an unusual degree beyond

173

the neural arch. It ends in a flat, roughened articular surface, as if intended
for the conjunction of another vertebra entering into the constitution of the
-sacrum. ‘The neural arches of the sacral vertebree are proportionately higher
than in the snapper, and they appear to have articulated movably with each
other by zygapophyses alone.

The diapophyses are about equally developed with those in the snapper.
The neural arch is not co-ossified with the centrum; nor are the ee Pop hye:
co-ossified with either.

Measurements of the sacral vertebze are as follows :

Lines

Length of the sacrum inferiorly -...........-..- Meh tee sabia ce h mu eye 22 18
Length of first sacral centrum.......-....-.---5.. 2 ERE ee Ae eee mn eet 7
Breadth of first sacral vertebra, with diapophyses .......-.--.-.---------+-+-- 9
ema SCCONGISACtAl COMEUM 5 <5 een ae chee = ans de mabe Sale we nee ee sono 11

Breadth of second sacral vertebra, with diapophyses........ -.-. .-.--- ++... 103
. Height of first sacral vertebra to end of spinous process....-.---...---------.- 13
Height of anterior articulation of first sacral centrum.....-.......--.. ----.-- 5
Breadth of anterior articulation of first sacral centrum.......--. -..-----....--. 5

An isolated vertebra, from Henry’s Fork of Green River, looks as if it
might be the first sacral of Chisternon undatum. The body is little more than
half the length of that of the last sacral above described, but its anterior
articular surface agrees in size, form, and roughness with the posterior sur-
face of the last sacral centrum just mentioned. The pleurapophyses have
about the same degree of development as in the snapper.

Fig. 10, Plate XVI, represents a caudal vertebra, obtained by Dr. Carter
near Lodge-Pole Trail. In construction it resembles the caudals of the
snapper, the centrum, as in this, being opisthocoelian, or having a cup behind
and a ball in front. The proportions of the vertebra accord best with the
more anterior caudals of the snapper, but its transverse processes are as small
as in the terminal caudals of the latter. Perhaps it may belong to Chister-
non, but the opinion is conjectural. If the former isolated vertebra belongs
to Chisternon, it is doubtful whether this second one does.

Fig.-7, Plate XVI, represents an isolated ilium of a turtle, found at Grizzly
Buttes by Dr. Carter. It resembles in its form that of a snapper, but is more
robust in proportion to its length. The inner surface at the upper extremity
is flat and longitudinally striated, but is devoid of the fossa existing in the
snapper. The length of the bone is 34 inches; the width of its upper end

? of an inch; the width at the lower end is 17 lines. From the form of the

174

bone [ would suspect that it belonged to Chisternon, rather than to either

Emys Carteri or Baptemys wyomingensis.
HYBEMYS.
HYBEMYS ARENARIUS.

Two little specimens, obtained by Professor Hayden, in the Tertiary for-
mation of Little Sandy Creek, Wyoming, appear to indicate a previously
undescribed turtle, to which the above name was given. ‘hey consist of
a detached marginal bone, and a fragment of a costal plate of a species
about the size of the common spotted turtle, Emys guttata. The bones are
unusually thick in proportion to their breadth, compared with those of ordi-
nary recent Emydes. Their surface is smooth and strongly marked by the
lines of separation of the scute areas. The costal ridge on the interior of the
costal plate is scarcely perceptible; the costal capitulum is rather stouter
than in Emydes.

The marginal plate represented in Fig. 9, Plate XV, is especially remark-
able, and it is upon its peculiarity that the genusis inferred. It would appear
to correspond with the ninth of ‘the series, and has the same form as in the
corresponding plate of ordinaty Emydes. The outer portion of the upper
surface, strongly defined by the groove of the costal scute, exhibits at its fore
and back part a half-circular boss, occupying the middle of the marginal
scute areas. As we may safely infer the other marginals to have the same
construction, it follows that the margin of the carapace is ornamented with a
circle of hemispherical bosses, each of which is crossed by the sutures of the

marginal bones.

ANOSTEIRA.
ANOSTEIRA ORNATA.

Among the many remains of turtles from the Bridger Tertiary formation,
submitted to my examination from time to time, by Dr. Carter and Professor
Hayden, there were a few isolated plates of peculiar character which were
described and referred to a genus and species under the above name. Sub-
sequently Dr. Carter discovered many parts of a shell of the same species,
which we have endeavored to collocate as represented in Figs. 1, 2, Plate
XVI.

Anosteira is a remarkable genus, very unlike any other turtle, previously

175

described, recent or extinct. The carapace and plastron, while being com-
pletely ossified as in Testudines, Emydes, &c., are ornamented in a manner
only seen to the same degree in the soft-shelled turtles. True, we see some-
thing like ornamentation of the same kind in some of the Emydes, but in
them the condition is comparatively feeble. The osseous shell also appears
to be devoid of the usual outlines more or less strongly expressed of the in-
vesting scutes. A few of the plates exhibit obscure lines, but I am uncertain
as to whether they accord with the areas of the scutes.

The outline of the carapace is broadly cordiform and somewhat resembles
that of the ordinary sea-turtles, but is not acute posteriorly as in these, being
obtuse as in the Emydes. The prominence of the carapace is moderate as in
the less elevated forms of the latter. It is uniformly convex, except that it
is acutely carinated in the median line posteriorly.

_ The margin of the carapace anteriorly is rather obtuse, but laterally and

posteriorly is quite sharp. It is broadly and concavely notched in front; the
first pair of marginal plates being the most prominent portions anteriorly.
Antero-laterally it is slightly concave, and from this position posteriorly is
uniformly convex.

The plastron with its bridges is flat, and is intermediate in its relative pro-
portions with that of the snappers and Emydes. The bridges articulate with
the carapace by gomphosis, as seen in Fig. 2. They join the marginal plates
from the fifth to the eighth inclusive. The extremities of the plastron are
both broken away in the specimen. .

The vertebral plates of the carapace are narrow coffin-shaped. Those an-
terior are nearly level; those posterior are acutely carinated.

The costal plates within exhibit no costal elevation, but are quite level, as
represented in Fig. 3. The costal capitula are unusually broad but thin.

The inner surface of the nuchal plate at the posterior border presents a
- pair of round articular processes for conjunction with the contiguous vertebra.

The upper surface of the carapace is ornate with rugosities. These are
obsolete on the vertebral plates. On the costal plates they appear as longi-
tudinal, undulating, and nearly parallel ridges crossing the plates. Internally
they are feebly developed and become more strongly marked proceeding out-
wardly.

On the marginal, including the nuchal and pygal plates, the rugosities are
finer, closer, more interrupted, and in part even granular.

176

Beneath, the rugosities of the marginal plates bave a decidedly radiant
appearance. The under surface of the marginals in advance of the axillary
notches, and the corresponding surface of the nuchal plate, are smooth or de-
void of the ornate rugosities.

The pygal plate and the contiguous marginals increase in thickness from
their free acute edge inwardly, so as to be wedge-shaped in section. ‘The
base of the wedge, directed toward the cavity of the shell, is strongly grooved
in the pygal plate, and gradually less so in the contiguous “marginal plates.
The groove contributes to the general cavity of the shell. Fig. 6 represents
a fore and aft section of the pygal plate, exhibiting the groove on its inner part.

The plates of the plastron exhibit their ornate ridges arranged im a radiat-
ing manner, as seen in Fig. 2, but they are less prominent than those of the
carapace. f

The shell of the specimen of Anosteira, from which the above description
was taken, in its entire condition, was about 5 inches in length in the median
line and about 44 inches in breadth.

Figs. 4, 5, represent two anterior marginal plates, showing that the species

reaches a much greater size.

TRIONYX.
TRIONYX GUTTATUS.

One or more species of the soft-shelled turtles (Trionyzx) are indicated by
an abundance of fragments of shells which have come under my notice in the
various collections of fossils from the Bridger beds. Anything like complete
shells appear to be rare, as the best preserved which has yet been submitted
to my examination is the portion of a carapace represented in Fig 1, Plate
IX. The specimen, attached to a mass of sandstone, was obtained at Church
Buttes, near Fort Bridger, during Professor Hayden’s exploration of 1868

The osseous carapace in its entire condition is estimated to have been
about a foot and a quarter in length, and, independently of the extension of
the free ends of the ribs, has nearly reached that breadth. The bones range
from three to four lines in thickness, except along the position of the costal
ridges and near the thinner edges. |

The carapace appears to have bad the usual composition of seven vertebral
plates, and eight pairs of costal plates back of the nuchal plate. It was mod-
erately convex, and the posterior border in the specimen is deeply scolloped.

177

The vertebral plates in the specimen, consisting of part of the second, third,
and fourth, are reversed coffin-shaped, and nearly twice as long as wide.
Their anterior border is convex, and the posterior border concave.

The fifth vertebral plate is smaller than the preceding, and becomes earlier
narrowed from the sides toward the back end.

The sixth plate is lozenge-shaped, about as long as it is wide, and occupies
the space between the truncated angles of the sixth and seventh costal plates.
The latter meet in the median line for more than half their width.

The seventh vertebral plate is a very small lozenge-shaped bone, with a
crucial ridge on its surface, occupying an interval produced by the truncation
of the contiguous angles of the seventh and eighth pairs of costal plates.

The costal plates, from the fourth to the sixth inclusive, are nearly of the
same width internally, and they successively become more widened out-
wardly. The seventh costal plate is rather wider at the extremities than
‘intermediately. The last costal plates are nearly as wide fore and aft as from
within outwardly.

The surface of the carapace is sculptured for the most part with broad,
rounded, and isolated concave pits resembling the impression of rain-drops on
a soft surface. Only near the outer border of the costal plates, where these
are preserved, do the pits become more or less confluent, usually in twos and
threes. The reticular ridges bounding the pits are broad and low, and often
as wide as the included pits.

Measurements of the specimen are as follows :

Lines
Menemmor pid: vertebral plate. 22. 22 2.5 eee ce nes wee ce eee eet eee 23
Maingmorthond vertebral: plate in fromt../../.---2.--- 2-22. ee ee ee ee eee 7
Width of third vertebral plate behind ..... UG toy eee ee eee 2
EeUNEOR OUR, VENECOAl Plate’ << /0 5. - = 22 ese meee moe cee ese nee wes 204
Wich or fourth vertebral plate in front......+.......5-....-..-.- Se, ae ee 74
Sv inbvor fourth vertebral plate behind .............:.2.02.20.22-06 eee ese eres 104
Length of fifth: vertebral plate ............-- She ee a eee Sean. See Ane ccoer 193
MACiMOnnibm vertebral plate im front...--...--.. 2.2... -- +--+ eee wesc cee eee eee 7
MMinehros nith vertebral! plate at middle.......--.-.--...-2---.302.00ee. 2 eee. S$
IMENT OU a Oe SORE VERLE DTA ALC clca.c) ee ca mw nc oa le cls snes eel eter wee ene vec 10
Width of sixth vertebral plate at anterior third........-..--....... EAN Sco 10
Menor OUseVeEnuMVverteoral PlAtO 2... - ese see ee ee ee ee ee sete e ween 54
Width of seventh vertebral plate at middle .................2.2-...0.5--- 005. 5
Width of fourth costal plate fore and aft at inner part ...-. eet ak ayale gens 23
Width of fifth costal plate fore and aft at inner part ...-...--.--..-.-.......- 22
Width of sixth costal plate fore and aft at inner part.......--...--............ 21
Width of seventh costal plate fore and aft at inner part.........--.....-.-- chat LOR

236

178

Lines
Width of eighth costal plate fore and aft at inner part -.................-- ey |
Length of sixth costal plate'ab middle oie. ae wee ene ae ee ss ee 58
Length of seventh costal plate at middle.....---- 220. .52--2b see ee kee eens 41
Length ofeiehth costal:plate: atmilld dle sa! % 22.9 ooh eps tae) oii toe ee 22

Many fragments, both of the carapace and plastron of soft-shelled turtles,
collected during Professor Hayden’s expedition of 1870, and subsequently
by Drs. Carter and Corson at various localities in the vicinity of Fort Bridger,
appear to be referable to the same species as the above.

A specimen consisting of the right half of a nuchal plate, with an attached
piece of a first costal, derived from the same locality as the specimen above
described, belonged to an animal about the same size. The width of the
scabrous portion of the nuchal plate in its complete condition was about 63
inches; its fore and aft extent 1$ inches. The sculpturing of the surface is
more interrupted or broken than in the specimen specially referred to Tvionyx
guttatus. 'Vhe reticular ridges are narrower and sharper, and exhibit a dis-
position to rise in points at their intersection.

A specimen consisting of an outer portion of an intermediate costal plate
measures 33 inches wide, and is 5 lines thick. The reticulation of its sur-
face is unbroken, but otherwise it resembles that of the nuchal plate just
described.

TRIONYX UINTAENSIS.

During my stay at Fort Bridger, in a trip to Dry Creek, Major R. S$.
La Motte discovered the nearly complete carapace of a Trionyx, which he
presented to the Academy of Natural Sciences of Philadelphia. The speci-
men is represented in Fig. 1, Plate X XIX, one-half the natural size. On first
view I supposed it to belong to the same species as the former, but compar-
ison of the specimen with that of Fig. 1 of Plate IV leads to the belief that
it pertains to a different one. |

The carapace is about 164 inches long and 16 inches broad, so that its
proportions are. reversed from those in our living Trionyx muticus. It is
about as convex as in the latter, and appears to have been slightly depressed
along the position of the vertebral plates, judging from that portion of the
shell back of the fifth costal plates, as in advance of this the specimen has
been crushed inwardly. The fore and back part of the carapace is truncated,
as in JZ. muticus. The posterior truncation, slightly sinuous, extends the
width of the last two pairs of costal plates. In 7. guttatus the corresponding

179

border occupied by the latter is convex, and exhibits three deep sinuosities—
the middle one and the one on each side, as seen in Fig. 1, Plate IX.

Eight pairs of costal plates succeed the nuchal plate. The second, fifth,
and sixth pairs expand considerably outward, more especially the last of
these. The others are of more uniform breadth. ;

The specimen possesses only six vertebral plates. Of these, the first is the
longest and widest. Its fore border is convex, and nearly in a line with the
suture between the nuchal and first pair of costal plates. The lateral borders
diverge to the back angles, which are truncated to join the second pair of
costal plates. ;

The second and third vertebral plates are nearly equal in size, and are
reversed coffin-shaped. The fourth plate is smaller, and oblong quadrate,
with convex borders.. The fifth plate is obverse coffin-shaped, shorter, but
wider than the former. he sixth vertebral plate has not more than half its
usual development. It is pentagonal shield-like, and is included between the
angles of the fifth and sixth costal plates.

- The posterior half of the sixth costal plates, and those succeeding them,
unite in the median line by a tortuous suture.

The surface of the carapace presents a nearly uniform reticular aspect
and the thickness of the bones is of the usual proportion.

The measurements of the specimen are as follows :

Inches
Space occupied by the six vertebral plates..............---.-+--.-+--+--- 104
Breadth of nuchal plate... ... a rte NS Sich he cai eo ania 4 ars) Kigins oi wa 94
eaten oF muchal plate im median line -:..-.-..-.-.----0.--- 200s. se nena. 24
Breadth together of seventh pair of costal plates .......-..--+----.-+-.--+-- 33
Breadth together of eighth pair of costal plates ...-.-..-..--. NM a Pete 34

Length. Breadth.

Lines. Lines.
First vertebral plate....-. ore ere oe epee Crea tig aig niais es 28 16
mecond wernevral plate <2... Jes. s.r te ee SRC tay ‘ 22 15
Hal MICn VOTES Wa eVGA ak misc chee o nikee wes ewe oe twlclg ee ween wee Se 22 3
Fourth vertebral plate ......--.......-. HOR eee ere eee eee 20 10
Fifth vertebral plate........-... MeN e a atk ee Wad wen elnino Seer ete 18 12

bay Gente Oca Mlaihe sae erent oS oy ths eat esas Suis wed oe SS os 113 11

180

Depth Depth

Length. internally. | externally.

Inches. Lines. Lines.
First.costal plate «05 2). 4:45'2 fa eee ae ee 6 29 32
DOCOnd Costas plate. <i. c oer <tc lard tee nea eee ee 8 22 38
Third costal plate... - 2.2.2. 0: 222. see ee ee ee ee eee 8 21 26
Fourthicostal: plate... 2220 +e as ehh a aad ae oe 8 23 26
Ritthpcostalcplate .- .cje\s::.: aie pete ne vt rte ca ae 8. 22 33
SERUEICOSG AI LAGO «re cts = aie ieee oe ete ene ees 7 18 42
Seventh costal plate .......... DNS isate td te lark nts 44 16 21

’ REMAINS OF TRIONYX OF UNDETERMINED SPECIES.

Small fragments of Trionyx shells, from the Bridger Tertiary strata, exhib-
iting a different kind of surface-marking or sculpture froni that of the specimens
referred to the preceding species, probably indicate others, or, perhaps, differ-
ent genera. :

A specimen found by Dr. Carter at Dry Creek, and represented in Fig. 11,
Plate XVI, is an outer fragment of a costal plate. It is not pitted as in
Tronyx guttatus, but is crossed obliquely by coarse ridges with the intervals
occupied by a lattice of narrower ridges. Probably the specimen may belong
to a species of Anosteira. .

Another fragment of a costal plate, from Little acy Creek, is represented
in Fig. 12 of the same plate. ‘This specimen differs from the former in being
crossed by widely separated ridges, with the intervals finely pitted.

Other specimens exhibit slight differences from the foregoing and from
those of Trionyx guttatus, but are too imperfect to enable one to form any
idea of their relationship.

Order Lacertilia.

. The lizards have vertebrae with concavo-conyex bodies, and have the teeth
co-ossified with the jaws. The skin is furnished with horny or bony scales.
True lizards, allied to the existing monitors, iguanas, and chameleons, appear .
to have been abundant and of varied character in the ancient Wyoming fauna.
Few remains of these-animals, described in the succeeding pages, have been
submitted to my inspection, but Professor Marsh has indicated and briefly
described twenty-one species of five extinct genera from fossils obtained
by him from the Bridger beds.

181

SANIVA.
SANIVA ENSIDENS.

An extinct lizard, to which the above name has been applied, is indicated
by some remains discovered during Professor Hayden’s exploration of 1870,
near Granger, Wyoming.’ The remains consist of portions of a skeleton, in a
fragmentary condition, imbedded in an indurated ash-colored marl rock. The
bones are black, and the hollows of the long bones, including the ribs and
phalanges, are occupied with crystalline calcite.

The remains belong to a lacertian about the size of the existing monitor
of the Nile, to which it appears to have been closely related. The bones
indicate a robust body, a long tail, and limbs with long toes. |

The vertebree resemble those of the Nilotic monitor in form and propor-
tions, and like them possess no zy gosphenal articulation.

A pair of dorsal vertebree are represented in Fig. 15, Plate XV. The body
is 4 an inch long inferiorly, and measures ? of an inch between the dia-
pophyses. The ball and socket extremities are twice the breadth of the height.
The ball measures 4 lines in breadth and 2 lines in height. The neural arch
laterally at the zygapophyses is nearly 8 lines long.

An anterior caudal has the same length as the dorsals, but is narrower.
The ball is of less width, but the same height. The hypopophyses for the
chevron are quite prominent, and are situated a short distance in advance of
the ball, as in the monitor.

~ A small detached tooth, imbedded in the same mass, in proximity to some
small skull-fragments, presents the form and constitution of those of the moni-
tors. -It is represented in Fig. 35, Plate X XVII, magnified eight diameters.
The length of the tooth is about 14 lines; its breadth, ? of a line; and its
thickness, $a line. It is compressed conical, feebly curved inwardly and back-
ward, sharp-pointed, has abruptly impressed trenchant borders, and is smooth
and shining. It is hollow, and has thick walls. The transverse section of
the base is rhomboidally oval, with acute poles.

In breaking eff portions of the rock containing the bones above described,
there was exposed what appears to be the anterior extremity of a maxillary
containing the remains of six teeth. The fragment is 4 lines long and 1$
lines deep. The teeth are pleurodont in character, but appear different in
form from the isolated tooth above indicated, and have more resemblance in

shape to those of the iguana. The specimen appears so small in its propor-

182

tions with the other bones, that it leads to the suspicion that it may not belong
to the same skeleton.

No scales were found in association with the bones in the same mass of

a -
rock.

4 °

he name Saniwa, according to Professor Hayden, is used by one of the

Indian tribes of the Upper Missouri for a rock-lizard.

SANIVA MAJOR.

Several fragments, discovered by Dr. Carter near the Lodge-Pole Trail,
crossing Dry Creek, would appear to indicate a larger species of Saniva. The
specimens are of a greenish hue and somewhat smooth or water-worn, and
were derived from a green sandstone stratum.

One of the fossils consists of the distal extremity of a humerus, repre-
sented in Fig. 14, Plate XV. It resembles in general aspect the correspond-
ing portion of the humerus of the monitor, but the shaft is proportionately
more robust,-and not so much narrowed toward the middle. It is occupied
by a large medullary cavity with compact walls, as in the humerus of a bird.
The internal epicondyle appears less prominent than in the monitor, in con-
sequence of the less degree of contraction of the shaft. The external epicon-
dyle does not reach upward to more than half the relative extent it does in
the monitor, and it is not perforated. The ulnar eminence is prominent in
front, but projects below to a less degree than the radial capitellum.

The breadth of the bone at the epicondyles is ? of an inch. The greater
diameter or breadth of the shaft at the broken end is 33 lines; the short
diameter is 24 lines.

Another of the fossils consists of a pair of dorsal vertebrae, represented in
Figs. 36, 37, Plate XX VII. They agree in al! respects with the two vertebre
referred to the former species, except that they are considerably larger.

The bodies of the vertebree inferiorly measure 7? lines in length and 105
lines in width between the diapophyses. The ball measures 5 les in breadth
and 3 lines in height. The neural arch laterally at the zygapophyses is 10

lines in length.

GLYPTOSAURUS.
Professor Marsh has described, in the American Journal of Science and

Arts for 1871, another genus of extinct lizards, under the above name, from
remains obtained in the Bridger Tertiary. He observes that “the head was

183

covered with large osseous shields symmetrically arranged and highly orna-
mented. Other parts of the body, especially the ventral region, were pro-
tected by rectangular, ornamented shields, united to each other by suture.
The teeth are pleurodont, and are round with obtuse summits. The dorsal
and caudal vertebra have the same general form as those of Varanus, but show
traces of a zygosphene articulation. /

Professor Marsh indicates eight species, mainly founded on differences in
the position, form, and ornamentation of the dermal osseous shields and the
form of the teeth.

Dr. Carter has submitted to my examination a number of specimens col-
lected by him at Grizzly Buttes, which in part or whole are attributable to
the same genus, and mostly to the species named Glyptosaurus ocellatus.

Several of the dermal shields from the trunk of the body are represented
in Figs. 13 to 15, Plate XVI, and several of the cranial shields in Figs. 16, 17,
of the same plate, all magnified two diameters.

~The dermal shields of the trunk are oblong quadrate, with the longer mar-
‘gins thick and roughened for sutural conjunction with one another. The ex-
tremities thin out for imbrication. The anterior extremity, which is over-
lapped by the shield in advance, extends a third or more of the length of the
plate, and is smooth. The posterior two-thirds or less of the shields are orna-
mented on their free surface with rounded knobs or tubercles, closely arranged
in more or less concentric rows.

The cranial shields are from four to six sided, and proportionately-of greater
thickness than the former. All their margins are roughened for sutural at-
tachment together, and their free surface is ornamented in the same manner
as the shields of the trunk.

Accompanying the specimens of dermal shields above described, there are
several detached vertebra. One of the specimens is a dorsal vertebra re-
sembling those of Saniva, but somewhat smaller, and, like them, presents no
zy gosphene articulation. It may probably belong to that genus. The other
specimen is an intermediate caudal vertebra of the same proportions of length
and breadth as in Saniva, but the ball and socket articulation is as high as it
is wide. It has no zygophene articulation, and the hypopophyses for the
chevron are immediately beneath the-ball of the body. The length of the

latter inferiorly is 23 lines.

184

CHAMELEO.
CHAMELEO PRISTINUS.

A small fragment of a lower jaw with teeth, discovered by Dr. Carter in
the Bridger Tertiary formation, is represented in Figs. 38, 39, Plate XX VII,
magnified three diameters. In every respect it agrees with the correspond-
ing part of the jaw of the living chameleons, but indicates a much larger
species. In a space of 5 lines the alveolar border is occupied by eight teeth
successively increasing in size from before backward.

The teeth are laterally compressed conical, with the borders in front and
behind somewhat extended and acute, and at the base produced into a minute
denticle. Externally the bases of the teeth are separated by perpendicular
furrows descending on the face of the jaw to the position of a finely perforate
horizontal line. Beneath the bases of the teeth internally there is a wider
and more conspicuous horizontal and perforated groove. Below this, toward
the rounded base of the jaw, the usual Meckelian groove is situated. The
outer face of the jaw exhibits two vasculo-neural foramina. The depth of
the lower jaw from the point of the last tooth of the specimen is 2$ lines.

FISHES.

The remains of fishes in the Bridger beds are not so abundant as one might
have supposed from the nature of their composition and the conditions of their
origin. Nevertheless, it is probable that fishes were abundant in genera,
species, and individuals in the great Uintah Lake and its tributaries, whose de-
posits form the Bridger beds.. The’same circumstances which removed the
less coherent parts of the skeleton from the interior of the many turtles, and
likewise scattered the bones of these and of the multitude of other reptiles
and of mammals, no doubt served to destroy the more delicate structure of
the fishes and to distribute their hard parts through the mud. It is probable

that future explorations may lead to the discovery of some strata of the Bridger
beds in which well-preserved forms of fishes may exist like those found in the
shales of the deeper beds of Green River.

The remains of fishes from the Bridger beds, which, with few exceptions,
were found by Dr. Carter and submitted to my examination, consist mainly of
smoothly enameled ganoid scales, a:‘few isolated specimens of vertebral centra,
portions of spingus rays, and fragments of jaws with teeth. My means of

comparison of these specimens with the skeletons of recent fishes are ex-

185

ceedingly meager, but they indicate forms which generally appear to be most
nearly related with our mud-fishes, (Amza,) and the gars, (Lepidosteus.)
Professor Marsh (Proceedings of the Academy of Natural Sciences of
Philadelphia, 1871, p. 105) has already noticed specimens from the same
locality, which he refers to two species of Amia about the size of A. calva,
and two species of Lepidosteus about the same size as the modern gar-pike.

AMIA.

Amita (PROTAMIA) UINTAENSIS.

A number of specimens, discovered by Dr. Carter on the buttes about ten
miles from Dry Creek Cafion, indicate a large fish related with the modern
Amia, but exhibiting sufficient peculiarity to pertain to a different genus, for
which the name of Protamia has been proposed.

Figs. 1, 2, Plate XXXII, represent one of the best-preserved specimens, a
- vertebral centrum from the fore part of the dorsal series. Its breadth is con-
siderably greater in proportion with its length than in Amia; it is more
prominent below ; hasa different transverse outline; has shorter parapophyses,
which also spring from a higher position at the sides, and the bottom of the
articular cones is situated considerably above the centre.

The centrum is nearly four times the width and three times the height of
its length. It is slightly curved from side to side with the convexity directed
forward. It is widest at the upper third, opposite the origin of the para-
pophyses, and is shortest at the sides intermediately. :

The articular cones have their bottom considerably above the center, and
are more minutely-perforate for the notochord than in Amia.

The sides-of the centrum are concave between the prominent articular
margins, and slant in a nearly straight line to the ridges defining the narrow
inferior surface. ‘The latter is concave, and the lateral ridges are obtuse, and
excavated in an oblong shallow fossa at their fore part.

The upper part of the centrum is transversely convex between the para-
pophyses. The articular fossee for the contiguous neural arches, as in Amia,
are in the form of the figure of 8, and their internal prominent borders form
the lateral limits of the bottom of the neural canal.

The parapophyses are short, stout processes projecting above the middle
of the centrum from its widest part, and ona line with the bottom of the
articular cones. |

246

186

The measurements of the specimen are as follows:

Lines.
Length of centrum inferiorly .......-.--...-.. ER PEN ce Sia ice ae). 5.6
Height of centrum anteriorly. -o asec = sce e oes See ee 15 ag aA Si 9 ke a i le 15.5
Width of centrum in line with the parapophyses.-.......-.--------.----.-.-+. 20.0

Another specimen from the same locality as the preceding is represented
in Figs. 3,4, Plate XXXII. It appears to be the centrum of an atlas, and
may probably belong to the same species as the former, though, judging from
its different aspect, to a different individual.

The centrum is transversely oval and slightly curved, with the convexity
of the curve directed forward. Its breadth is two and a half times the height,
and over five times the length.

The anterior surface is nearly flat and somewhat uneven, and just above
the center is depressed into a concave pit about one-fifth the diameter of the
centrum. The posterior surface presents the usual cone with its bot-
tom just above the center.

The sides of the centrum are concave between the articular borders, and
bear no trace of parapophyses. ‘The lower part is more flat, and presents a
shallow fossa on each side of a median concavity. ‘The fossz for the neural
arch are quite promivent at their contiguous borders.

The measurements of the specimen are as follows :

Lines
Length of centrum, inferiorly... 64 02 onig co ne gee a ne 4
Heightof centrum anteriorly" es. 6 a eee odes 2 14
Breadth of centrum-at middle<- 2: s-j-. 222s. pee aG.te J 22

A third specimen, from the same locality, less well preserved, resembles
the first one, and belonged apparently to a somewhat smaller individual. Its
parapophyses barely project beyond the sides, and are hollowed at the end.
The ridges defining the inferior surface from the concave sides are barely

excavated.
Its measurements are as follows:
Lines
Length ofcentrum inferiorly®. 26) ee a gett aa 5.5
Height of centrumianteriochyee ee ee eee eee eee eee ee ee POSER... 15.5
Breadth of-centrum ‘at the upper birds eas see ese aoa et 18. 25

A series of three specimens, with a portion of another, from the same
locality as the preceding, appear to correspond with the anterior vertebre of
Amia from the second to the fifth inclusive. The fragment resembles the
lateral half of the atlas above described, but is bi-concave. The other speci-
mens resemble the first and third ones above described in the form of the

187

centrum. In the third vertebra the parapophyses are high up, as in the first-

described specimen. In the succeeding two they spring from near the middle

of the sides of the centrum. |
The measurements of the second cervical are as follows:

Lines:

Pemeanhwiol cenkEnm: Mferiorly 55 ce. wa wsie = 222g ts eie Scie Se swe 4
Depth of centrum anteriorly ...... - shoes alegre ih le ee 1
Erevan oOrcentrum at mIddlett. 0 cn . Ha ise.) faa = slae es ho gee oem eee se eee 20

The measurements of the fifth vertebra are as follows :

; Lines

emai eOmeECNLTIMMMIeMOLy <<). 525s sae og) Soe eat sees cee toe e eee 3.6
ene MEO COMUCMMMPAMLCIIOULY = = 25 - a aes we mamas cel pew se ene ee ee tee 12.0
Breadth of centrum at middle, on line with parapophyses .......-.....--.-.-- 17.0

A series of three posterior dorsal centra, from the same locality as the
preceding specimens, perhaps belong to the same species, but, from their
appearance, most probably to another individual. They are somewhat dis-
torted from pressure, and appear in the original condition closely to have
resembled corresponding vertebree of Amza calva, but are nearly three times
the breadth, and scarcely twice the length.

The three specimens together, represented in Fig. 5, measure 16 lines in
length.

The anterior of the three presents the following measurements :

Lines.
Length of centrum inferiorly.........-.-..-- ESS ere wre e aden amr etes nen eet) 5
ORC OULCUUN DULCTIONY: 62-54 oa00-50 csc once sees. tec slsiss eel eels aus
Breadth of centrum inferiorly, opposite the diapophyses........-.........-...... 14

A specimen from Dry Creek, consisting of a mutilated basi-occipital, about
the size of that of the alligator-gar, differs considerably as well as from that
of the mud-fish. It is represented in Figs. 6, 6", and may perhaps belong to
Protamia.

The articular conical cup has its acute margin scolloped, as seen in Fig. 6
The deep median groove on the under part of the bone in Amia and Lepi-
dosteus reaches the articular margin, but in the fossil, stops the fourth of an
inch short of it. On each side of the bone at the articular margin corresponding
with the lateral notch there is a conspicuous fossa not seen in the genera just

named. In advance of the fossa on each side of the median groove there is
a broad, slanting, flat surface, longitudinally ridged, of which there is likewise
no exact counterpart in Lepidosteus, but appears to correspond with a smooth
surface occupying the same position in Amia.

188

AmiA (PROTAMIA) MEDIA.

Figs. 7 to 9 represent a vertebral centrum, obtained at the junction of the
Sandy and Green Rivers, during Professor Hayden’s expedition of 1870. In
its form and proportions it resembles a centrum from near the fore part of
the dorsal series of Amia calva, but pertained to a species double the size.
It presents several peculiarities which render it probable that it belongs to a
related genus. The sides of the centrum are less contracted than in Amia,
and the pair of ridges beneath are substittted by a pair of oval pits. The
parapophyses project transversely just above the middle, and are very short.

The measurements of the specimen are as follows:

Lines
Hengeth, of centrum mileriorly.. 2206s ao22 tke se tees ae ee ee 5.5
Height of centrum: cu icx cd DRS) sete SURE ees os tte Ae 10.2
Breadthiof centrum... 2s 22). Sen tiger oa ek aie os eye lee ee 13.0

Figs. 10, 11 represent a vertebral centrum, found by Dr. Carter on Dry
Creek. It resembles a centrum of Amza calva from the back of the dorsal
series, but is double the size. It presents beneath a pair of grooved ridges,
as in A. calva.

The specimen measures as follows :

Lines
Length of centrum inferiorly ..02-.4- 9: setae ee es eo 4.0
Height of centrum {220 ose we scien yoke Sow Se Bio ies oo te ee ae ee 7.6
Breadth+of. centrum. --haee a2 Goce ee eee Jeecae tthe ie 8.6

Amia (PROTAMIA) GRACILIS.

Figs. 23, 24, Plate XXXII, represent a vertebral centrum found by Dr.
Carter, together with a number of ganoid scales, opposite the second cross-
ing of Henry’s Fork of Green River. ‘The centrum has a different color from
the scales, and clearly did not belong to the same fish. It is from near the
middle of the dorsal series, and pertained to a smaller species than Amza
calva The two ridges beneath the centra of the latter are substituted by
two oblong fosse.

The measurements of the specimen are as follows:

Lines
Length of vertebral centrum inferiorly .- -. . PSOE? A OR eae a Ses
Height of vertebral centrum <.........-------- Soe SN SERENE NE Ol 3.4

Breadth of vertebral centrum....-...---.-------:--- sie 2 eS ee Be aS

189

HYPAMIA.
HfYPAMIA ELEGANS.

Figs. 19 to 22, Plate XXXII, represent a vertebral centrum, found by Dr.
Carter on Dry Creek. It is from near the middle of the dorsal series, and
evidently indicates a genus distinct from but nearly related with Amia. As
in this, the centrum is short in proportion with its breadth, and it presents
sutural impressions for a cbntiguous pair of neural arches. The articular
cups have their bottom central and minutely perforate. The sides below the
parapophyses are concave, and converge to a median prominence, which is
excavated into a pair of fossee, separated only by a linear partition. The
parapophyses are cylindroid and comparatively short.

The measurements of the specimen are as follows :

Lines

| ancien Gt regina rhrclanin (es ato) ¢ haa ae er res are ane anne 2.2
Depth of centrum anteriorly...-.-...----- Hise Sack Ae SAS BAe Seiten ee ees 6.5
Preqiubror centrum anteriorly .-..-.. --.--.------:-+2----- Bs Ce a oe ache = BG
breadth of centrum, including parapophyses.....--..-..-.-. 22.22.2202 eens: 8.5

The specimen indicates a species about one-third larger than Ama calva.
LEPIDOSTEUS.
. LEPIDOSTEUS ATROX.

During Professor Hayden’s expedition of 1870, James Stevenson collected
a number of remains of fishes at the junction of Big Sandy and Green Rivers,
Wyoming. The specimens consist of isolated vertebral centra, ganoid scales,
and portions of jaws with teeth, all of a black hue. Among them are several
vertebree indicating an extinct species of gar larger than the existing alliga-
tor-gar, Lepidosteus ferox.

Figs. 14, 15, Plate XXXII, represent the centrum of a vertebra from a
position in advance of the middle of the dorsal series. The length of the
centrum is not greater than the breadth. The extremities are hexahedral in
outline. The under surface is flat, and ornate with longitudinal and somewhat
reticular wrinkles. The sides beneath the parapophyses are impressed into
a deep fossa. The neurapophyses are likewise impressed at the sides with a
deep fossa, and a second deep pit occupies a position just behind and above
the parapophyses. These appear rather narrower than in the alligator-gar,
and are less anterior in position.

190

The measurements of the specimen are as follows :

Lines
Length of centram inferiorly’): - ease de ee ee = trey eine wenn a 8.6
Breadth of centram Posterionly: . 2... .- ce eee eee oe BEES EONS SA 2 =
Height of centrum posteriorly: s2a.5. 4- tise nce eee be oe ee eee ae en ee 6.0

Another specimen, consisting of a caudal centrum, perhaps belongs to the
same species. It has about the same length as the preceding, and is hexa-
gonal in outline at the ends. Its sides present a strong longitudinal ridge
separating a deep fossa below from another above.

The measurements of the specimen are as follows:

Lines,
Length of centrum inferiorly .. 252). 22 <2 asic) 2 Ss nee = 2 er 8.4
Breadth of/centrum posteriorly ---4-<- 222-522. 23-22. s-e-- =e 4,4
Height-of centrum posteriorly,.2 =. 2-2 ~. 6 =< einen oe ee ets eee ain =r 4,8

LEPIDOSTEUS ———— ?

Accompanying the preceding specimens there are two vertebre of another
species of Lepidosteus. One of them is a posterior dorsal centrum, and is
represented in Figs. 16, 17. It is about as long as the corresponding centra
of the gar-pike, Lepzdosteus osseus, but is proportionately broader and more
robust. Its articular ends are hexahedral, with the upper and lower borders
slightly emarginate. The lower surface of the centrum is nearly flat, nearly
level, contracted at its anterior third, and deeply grooved along the middle.
It is bounded by ridges defining it from the deeply impressed sides.

‘The other specimen is the centrum of a caudal nearly as long as the former,
but narrower in proportion with its difference of position in the series.

The measurements of the specimens are as follows:

Lines
Leneth of dorsal centrum/inferiorly . =... <.-.$22-2- e225 2 ee eee 3.4
Length of caudal centrum inferiorly..-.--.- 2.....--.2- 22.202 5-= 22 ee 5.0
Breadth of dorsal centrum posteriorly 20-2. 2220.6 - ie ass. Jt eee D.4
Breadth of caudal centrum posteriorly ..-.....-----.------- RP ve = = 3.0
Height of dorsal centrum posteriorly....... PR eee ey Mes Ss so = 4,2
Height of caudalcentrum® postertorly.2- 2. -. 4-6-5222 = oo ee 3.2

These specimens may, perhaps, belong to one of the species indicated by
Professor Marsh.

Figs. 27 to 30 represent several ganoid scales, accompanying the preceding
specimens, which probably pertain to the smaller of the two Lepidostei.
They are covered with perfectly smooth, shining ganoine without markings.

Fig. 25 represents a fragment of the fore part of the right ramus of the

lower jaw accompanying the former specimens. Its construction is similar

191

to the corresponding part in the alligator-gar, but is proportionately not so
thick or robust near the symphysial end. The lower surface is reticulated
with round meshes, and the ridges of the net are ornate with shining trans-
lucent tubercles.

The dental groove exhibits the remains of a row of large teeth, of which
one retained exhibits the same character as those. of the living gars. The
outer edge of the groove was also furnished with minute teeth, but the inner
edge exhibits no trace of these organs.

LEPIDOSTEUS SIMPLEX.

Some remains of a Lepidosteus, together with some fragments of a turtle-
shell, were collected near Washakie Station, Wyoming, by James Stevenson,
during Professor Hayden’s exploration of 1870. The remains of the Lepidos-
teus consist of a mutilated basi-occipital and three succeeding vertebral cen-
- tra, together with several small jaw-fragments and a number of large ganoid
scales.

The basi-occipital and vertebral centra, represented in’ Fig. 18, Plate
XXXII, resemble in form and proportions those of alligator-gar, but are
smaller. ‘

A tooth, represented in Fig. 26, contained in one of the jaw-fragments
agrees in character with the larger teeth of living gars. The outer edge of
the same jaw-fragment is furnished with smaller and more curved teeth of
the same kind.

Figs. 31, 32 represent two lozenge-shaped scales of less breadth but thicker
than those of the alligator-gar. The enamel surface is flat, smooth, and
highly polished, and exhibits no markings except one or several minute puncta
near the center.

Fig. 83 represents a similar scale, which appears to be traversed fore and
aft by a canal communicating by a short cleft with the outer surface. The
cleft is directed backward, and is protected by an angular elevation of the
anterior border.

Fig. 84 represents another scale of a different forin, probably from the
median line of the back.

The measurements of the basi-occipital and vertebral centra are as follows:

Lines
Breadth of the articulation of the basi-occipital .-..........--..-...-.......-- 10.0
Height from lower groove to edge of occipital foramen...........--5 ..-....-- 5.0

SMG Cit WAS G WC RS VEEL) aU ee 4.0

192

Lines
Breadth of first veriebral centrant oto e-o ee e ee sc eo ~ Soo mee ee
Length of second ‘vertebral contami ..a1tet. + ele We ee ce wcriele's secs colette see eee 4.4
Breadthof second \vertebral:centram:. ©2222 © ssbb ee ae ete» ee eee ce eee 7.6
Length of third vertebral centrum ........-. bide Sap P Amek fGen 3, 5.0
Breadth ofthird vertebral icentromy.. 1 eee eee ee eee eee Po bee 6.8

A number of large ganoid scales, of the & same character as the preceding,
were collected in a sandstone stratum on Little Sandy Creek, during Pro-
fessor Hayden’s expedition of 1870. Several of these selected from the collec-
tion are represented in Figs. 35 to 38.

A number of similar scales were obtained by Dr. Carter in the vicinity
of Fort Bridger. Figs. 39 to 42 represent several of the scales selected from
the collection. |

Fig. 43 represents a scale of a Lepidosteus found in association with the
large saber-like canines described in the preceding pages, and supposed to
belong to Uintatherium.

LEPIDOSTEUS NOTABILIS.

A vertebral centrum partially imbedded in a yellowish sandstone contain-
ing casts of shells was obtained near Washakie, Wyoming, during Professor
Hayden’s exploration of 1870.

The centrum is represented in Figs. 12, 13, and appears re indicate a fish
related with Lepidosteus, but probably of a different genus. It pertains to
an anterior dorsal, and is about the size of a corresponding centrum of the
alligator-gar, but has the parapophyses much shorter. The centrum also
differs in shape from those of the alligator-gar. The lower surface is broad
and flat, and is marked with longitudinal curved and furcate ridges. The sides
are perpendicular and depressed in a deep fossa beneath the parapophyses
In the alligator-gar the sides slant outwardly from the lower surface.

The posterior end of the centrum of the fossil is four-sided, with the
widest border above and convex, the shortest below and straight, and the
lateral borders slanting with a slight sigmoid course.

The skort parapophyses project from the upper part of the centrum nearly
from the middle.

The measurements of the specimen are as follows:

Lines
Iheneth of centrum inferiorly 24.2 B= --2 eee ee ee oc ieee 8
Height of centrum posteriorly......-.--- eps a A EY = 9
Breadth’of centrum at. upper Path... -.t2e a2 sos ce: 22+ 2s ee 10
Breadth-ot centrum-at lower part... 2 -.--s5e---<:s2--: +++) eee eee 6

Breadth of centrum, inclading parapophyses.-....-..---.:-.--.----. -- Pee 13

193

PIMELODUS.
PIMELODUS ANTIQUUS.

Among the fossil-fish remains of Professor Hayden’s collection from the
junction of the Big Sandy and Green Rivers, there are a number of fragments
of pectoral spines and a few jaw-fragments of a species of cat-fish.

The pectoral spines, of which two fragments are represented in Figs. 44,
45, Plate XXXII, are like those of our living cat-fish. A fragment compris-
ing about two-thirds of the symphysial portion of a dentary bone, -Fig. 46, re-
sembles the same in the recent cat-fish, and, as in it, was covered with a broad
card-like surface of teeth. The breadth of the dentary surface near the sym-
physis is 34 lines. The pectoral spines have ranged from an inch to upward
of 2 inches in length. The size of the specie was from a foot to 18 inches.

PHAREODUS.
PHAREODUS ACUTUS.

Accompanying the remains of gars and cat-fish, from the junction of the
Big Sandy and Green Rivers, there are many fragments of jaw-bones and
others with teeth, evidently not belonging to either of those genera of fishes.
They also present sufficient peculiarity to render it probable that they may
not belong in the same family with Amia, and therefore probably not to the
closely allied genera supposed to be indicated by the vertebral specimens
described in the preceding pages. ‘The means of comparison at my command
are too scanty to enable me to determine the athnities of the fish to which
the fossils pertain.

Figs. 49, 50, Plate XXXII represent two of the best nae and more
characteristic of the specimens, consisting of fragments of dentary bones.
These.are proportionately deeper and stronger than in Amia. They support
a single row of long teeth at the border, and possess no patch of smaller
teeth internally such as exist in Amia.. The teeth are cylindro-conical, with
their somewhat thickened bases close together and firmly co-ossified with the
jaw. ‘Their shaft is straight and not curved as in Amia, but the sharp coni-
cal apex is bent inwardly. | .

Figs. 47, 48 represent fragments of premaxillaries. In these the teeth
are of the same character as in the dentary bones, but are less bent, at the
tips.

25 G

LSet

Vig. 51 represents what I suppose to be a fragment of a maxillary of the
same fish. It is provided with teeth as in Amia, Salmo, and some other
genera.

Associated with the specimens of the character above described there are
a number of others, consisting of small fragments of bones with close patches
of short conical teeth, like the vomerine and other similar patches of teeth of
Amia. ar
The dentary fragment of Fig. 49 contains the remains of a dozen teeth in
the space of 11 lines. The specimen of Fig. 50 contained thirteen teeth within
‘a space of 10 lines from the symphysis. Of the retained teeth the last is the
longest, and measures nearly 3 lines. The others are about 24 lines in length.
The premaxillary fragment of Fig. 48 contained seven teeth in a space of as
many lines. The first tooth is the longest, and measures 2% lines. In
the other fragment of Fig. 47, ten teeth occupied a space of 84 lines.

The genus supposed to be indicated by the specimens has been named from
the light-house-like form of the teeth.

REMAINS OF FISHES FROM THE SHALES OF GREEN RIVER, WYOMING.

In Professor Hayden’s Preliminary Report on the Geology of Wyoming
for 1870, p. 142, the author remarks that soon after leaving Rock Springs
Station, on the Union Pacific Railroad, the Green River group is seen on the
bluff hills on either side of the road to the entrance of Bitter Creek into
Green River. In the valley of the latter remarkable sections of strata
are exposed to view. The group he calls the Green River shales, because the
strata are composed of thin layers, varying in thickness from that ofa knife-blade
to several inches. The rocks all have a grayish-buff color on exposure, some-
times with bands of dark brown. ‘These darker bands are saturated with a
bituminous matter which renders them combustible.

About two miles west of Rock Springs Station there is an excayation on
the railroad which has been called the. Petrified Fish Cut, on account of the
thousands of beautiful and perfect fossil-fishes which are found on the surface
of the thin shales, sometimes a dozen or more on an area of a square foot.
Remains of insects and aquatic plants are also found in the shales, and in one
instance a well-preserved portion of a feather of a bird was discovered.

A large collection of fossil-fishes from the Petrified Fish Cut, obtained by
Professor Hayden in 1570, was submitted to Professor Cope, who has described

the different forms in the report above mentioned.

195

The first of the fossil-fishes of the Green River shales was discovered by
the late Dr. John Evans as early as 1856, and was submitted to the examina-
tion of the writer. Several specimens, both of the buff-colored and dark
bituminous shales, containing fossil-fishes, have been presented to me by
Judge W. A. Carter and Dr. J. Van A. Carter, of Fort Bridger, Wyoming.

Professor Cope describes seven species, including one of those described
by me, from the Green River shales: Two are named Clupea humilis and
C. pusilla, and a third Osteoglossum encaustum. The others are referred to
two extinct genera with the names of Asineops squamifrons and A. viridensis,
Erismatopterus Rickseckert and E. levatus.

CLUPEA.
CLUPEA HUMILIS.

The species was originally described in the Proceedings of the Academy
of Natural Sciences of Philadelphia for 1856, page 256. It was indicated
from a specimen consisting of an impression of a nearly complete fish ina
piece of shale, which looks like one-half of a rounded, water-worn fragment.
The fossil was found by Dr. Evans on Green River, and was stated by him
to have been derived from the Tertiary rocks of that locality. The fish is
represented in Fig. 1, Plate XVII, of the natural size. It has the ordinary
form of living species of herring, and presents the characters of the genus.

This small herring in its total length has measured about 33 inches. The
back is slightly arched, and the dorsal fin is situated just in advance of the
middle. The ventral border is strongly arched, and is rather abruptly nar-
rowed from the anus. The ventral fins are placed beneath the back of the
middle of the dorsal fin. ‘The head is pointed. The tail is deeply forked,
and its pedicle is rather narrow.

The number of vertebre appears to be about thirty-four, of which at least
twenty are dorsal, the remainder caudal. The notochord appears to have
_ extended continuously through the perforated vertebral bodies.

The depth of the body at the fore part of the dorsal fin is four and a half
times less than the length. The length of the head slightly exceeds the
depth of the body. The eyes are large. .

The pectoral fins are destroyed, but their connection with the body was
just below the position of the operculum. The ventral fins contain seven

rays.

196

The dorsal fin appears to have had thirteen rays, of which the second was
the longest, and from which the others gradually decreased. The anal fin
contains fourteen rays. The caudal fin between its two extreme outer and
longest rays, inclusive of these, appears to possess twenty rays.

The ventral carinated spines are twenty-five. Accessory ribs project from
the vertebrae and ordinary ribs in the usual manner in the herrings.

Measurements of the specimen are as follows :

Lines.
Total length of the fish....- sal spel aera awiePay isi Sees le ate mmin Slain ed a pa a rrr 45
Length to commencement of the tail::....--.-.-. «, sess-.---- + os +20 eee 34
Depth of body in front of dorsal fin...----1. 2 0-2-2 so 5.--2.2 6225 oe 10
Depth abjamuis 27-2 5 oa Ae ls oyn ara ee meee ole ofall amit te ote 6
Term tot Gere a eee eae aloe ee erege emia ee ete ieee rie 103
Depth ofithe head _. --).- 55... 2. eee eee ee eee eee eee eee eee eee 2S tie 84
Length of the tail. c2cn.s.2eeee Seed see leicester eee ee see 10
Depth ‘of pedicle of the tail... 22-2. - 2 poem, o andes pose ae 4
Distance from snout to commencement of dorsal fin...---.... ie 17
Distance from snout to anus ..-...--.-. till: debiee dawelaco es sale ae 27

CLUPEA ALTA.

A slab of shale obtained from the so-called “ Petrified Fish Cut,” and sub-
mitted to my examination, contains ten herrings, in which the bones and
scales are preserved, and stained of a dark-brown hue. The vertebra, where
broken, exhibit the position of a continuous notochord occupied by hyaline
chalcedony that looks like the original substance of the latter itself. The
most complete and largest of the fossil-fishes is represented of the natural
size in Fig. 2, Plate XVII.

These fishes appear to belong to a different species of herring from the
former, especially distinguished by the greater proportionate depth of the
body and the more arched dorsal border. In most. other essential characters
the two appear to agree. It has the same number of vertebree and of ventral
carinated spines. ‘The fins also, so far as can be determined, appear to con-
tain the same number of rays.

The other specimens on the slab, though smaller, exhibit the same, or
nearly the same, proportionate depth of the body.

The measurements of the specimen figured are as follows:

Lines
Rofaleneth ok the TShe st woeeerens Gener ne neh ey te) ese ee eee 50
Length to commencement of tail. .--.......-- BP aaise nies Wiss $6, vctrie oe 38

Depithyotibody.in front of dorsal fin 2.-0. Soe oe wenn sss. <i One eee - 143

197

Lines
IDEDID Bik BOS 2c 6 tebe dGee 5 aS ee cue cis i eee ENE Ser ey eRe ee eater eine roan on. ote 94
TEDL OF IGE! oct Sak ee ei ace aera sae aa Ma he a nee Pare aide a 12
LDVECDD GLP INQ IOL = © 2 sy See eet OES a ne en dae enor et ee 104
Length of tail.....-... Mains eA ae TIES Cy A Pere re ete EE ete oe Ad ee Oe eer 11
LVEVDIID, OLE OCOIB ONC A) PAE SE, SEI OAs Bee ek ee OI ee Uae ae ee ee ee 5
Distance from snout to commencement of dorsal fin-.......-.-...--..--- eee 203
Distance from snout to anus ...--..--.-.--.--- Oe Arce o eee he, On one terre ene 31

DESCRIPTION OF REMAINS OF MAMMALS FROM THE TERTIARY
FORMATION OF SWEETWATER RIVER, WYOMING.

A small collection of fossils, consisting of the remains of mammals, was
obtained, during Professor Hayden’s expedition of 1870, on Sweetwater
River, eighteen miles west of Devil’s Gate, Wyoming. |

Professor Hayden, in his Preliminary Report of the Geological Survey
of Wyoming, 1871, page 32, in relation to the locality whence the fossils
were obtained, makes the following remarks: “Near Cloven Peak, fifteen
miles west of Devil’s Gate, there are some bluff-banks on the south side
of the Sweetwater, about one hundred feet high, which indicate the exist-
ence of quite modern Tertiary beds, like those on the Niobrara River.
They are composed of indurated sands and marls of a light-gray or cream
color, and are in appearance precisely like those seen on the Laramie River,
and many other places, which I have usually regarded as of the Pliocene age’
Still farther to the westward are numerous exposures of these beds, which
are weathered into the usual fortification-like forms, and scattered around
their base are large numbers of remains of extinct mammals and turtles,
apparently identical with those found on the Niobrara. They occur in the
same beautiful state of preservation.”

Professor “Hayden’s view of the age of the formation is confirmed by the
zoological character of the fossils, which are nearly related with those from
the Phocene Tertiary sands of the Niobrara River, and are, without doubt,
of a much more recent date than those of the Bridger beds.

The specimens submitted to my examination consist of fragments of jaws
with teeth, portions of the larger limb-bones, small bones of the feet, and a
few mutilated vertebree. Most of them pertain to a species of Merycocheerus,
an animal nearly related to Oreodon. A few apparently belonged to a smaller
species, and several to a small equine animal. The others remain undeter-
mined for want of ready means of comparison.

The fossils are all isolated specimens, which were picked up from the sur-
face of the ground. Usually they are perfectly free from adherent matrix.
They are white in appearance, and resemble recent bleached bones. They

: £99

have lost their bone-cartilage, and are hard and brittle, though not friable.
They are not in the least degree water-worn, and present no appearance of
having been submitted to great pressure, as is so frequently the case with the
ossils from the Cretaceous and Eocene formations of neighboring localities.

MAMMALIA.
Order Ruminantia.
MERYCOCHGRUS. :
MERYCOCH@RUS RUSTICUS.

The genus above named was originally characterized from some remains,
discovered by Professor Hayden during Lieutenant Warren’s expedition of
1857, in a bed of dull, fine-grained grit, on the head-waters of the Niobrara
River, near Fort Laramie, Nebraska.

Merycocheerus pertains to the same family as Oreodon, a genus character-
ized from a profusion of remains from the Miocene Tertiary deposit of the
Mauvaises Terres of White River, Dakota. The general construction and
form of the skull appear to be nearly the same, and such, also, is the case
with the number, constitution, and relative position of the teeth. There are,
however, certain peculiarities distinguishing the two genera.

The molar teeth of Oreodon have, comparatively with those of most genera
of existing ruminants, short crowns as in the deer; and, as in this, at matu-
rity they are all inserted alone by fangs. In Merycochcerus the crowns of
the molars are proportionately longer, and in the mature condition of the ani-
mal, while the anterior ones were fully protruded, the posterior ones, though
in functional position, were only partiaily protruded, and continued to advance
as they were worn away. The difference between the two genera, Oreodon
and Merycochcerus, in respect to the comparative length of the molar crowns,
is like that existing between the molars of the deer and the ox, but not to
the same degree. While the condition of the teeth of Oreodon corresponds to
that of the deer, those of Merycocheerus rather hold an intermediate condi-
tion to those of the deer and the ox.

In Oreodon, when the last of the molar series was fully protruded so as to
be inserted by the fangs alone, the anterior molars might still be in a condi-
tion to exhibit very conspicuously the anatomical characters of their triturat-
ing surfaces, as displayed in Plate VII of the Extinct Mammalian Fauna of

200

Dakota and Nebraska. In Merycochcerus, on the other hand, before the
crown of the last molar was fully protruded, already the anatomical characters
of the triturating surfaces of those in advance were, to some extent, destroyed ;
and in the case of the first true molar completely obliterated, in this state pre-
senting simply a broad dentinal surface bordered with enamel. This condi-
tion is represented in the Fig. 3, of Plate X, of the same work just mentioned,
though in this case the specimen belonged to an individual past maturity, and
the last molar is fully protruded.

Another distinctive character in the teeth of Oreodon and Merycocheerus is
expressed in the less degree of transverse symmetry of the crowns of the
premolars in the latter. In Oreodon their various measurements are more
uniform, and the summits of the principal constituent lobes of their crowns are
nearly or quite median, and they nearly retained this relative position as the
teeth were worn away. In Merycocheerus the length and fore and aft diame-
ter of the crown exceed the transverse diameter except in the last upper one;
and the summits of the lobes of the premolars, especially in the upper ones,
are.more or less in advance of the middle of the crowns, and they likewise
retained this relative position as the teeth were worn.

In the original description of Merycocheerus, its distinction from Oreodon
was mainly founded on peculiarities of the skull; the differences in the teeth
above noted, especially those in the proportionate length of the crowns of the
molars, and their relative mode of protrusion, were not recognized. This
want of appreciation of the distinctive characters of the teeth of the two gen-
era arose from the observations having been made on the jaw-specimens of
Merycocheerus advanced beyond maturity, in which all the teeth were fully
protruded, and in this condition did not strikingly differ from those of Oreodon.

A number of other fossils, discovered by Professor Hayden in the Pliocene
sands of the Niobrara Valley, and described by the writer at the same time
as those referred to Merycochcerus, from the difference in the proportionate
length of the molar teeth in comparison with those of Oreodon, were referred
to another genus with the name of Merychyus. In the same manner this
was supposed to differ from the Merycochcerus; and though subsequently, in
the preparation of the ‘ Extinct Mammalian Fauna of Dakota and Nebraska,”
it was suspected that these two genera might prove to be the same, it was
not until the present moment the suspicion appeared to be confirmed. From

present observations and reflection, [ am under the impression that Oreodon

201

and Merycocherus are two quite distinct though closely allied genera, of
which the latter is geologically the later, and, perhaps, the successor by evolu-
tion from the former. Merychyus would appear to be the same as Meryco-
cheerus, and the fossils which had been referred to it belong to the same geo-
logical horizon.

Of the specimens originally attributed to Merychyus mayor and M. medius,
too little of the corresponding parts were preserved in such a condition as to
enable us to make a comparison of the upper jaw and face with the same
parts in Merycochcerus to ascertain how far they are like one another. ‘The
position of the infra-orbital foramen, which appears to be nearly or quite con-
stant in a species, or varies but slightly in several species of a genus, in the
jaw-specimen referred to Merychyus maor is placed above the last premolar.
It oceupies the same position in Merychyus elegans ; and in the upper jaw of
a young animal, referred to Merychyus médius, it is placed above the last
temporary premolar, therefore agreeing in position with that in the adults of
the other two species. In Merycocherus proprius the position of the foramen
is further back, above the interval of the first and second molars, and this is,
also, its position in the upper jaw of the Sweetwater species named Meryco-
cherus rusticus.

This difference of cat aga is probably related with a difference in the shape
of the face, which in Merycochcerus is rather abruptly narrewed in advance
of the zygomata, as in the hog. The face of Merychyus I suspect rather to
be more like that of Oreodon, narrowing gradually forward from the position
of the ofbits and zygomata, as in the peccary.

Admitting the three genera, Oreodon, Merycocherus, and Merychyus, their
distinctive characters, so far as ascertained from the materials at command,
would appear to be as follows:

Orropon.—Molar teeth with short crowns, as in the deer; and, as in
this, at maturity inserted by fangs. Anterior premolars straight, with the
diameters nearly equal, and with their points median or nearly so. Face
gradually convergent, conical. Infra-orbital arch narrow or of moderate
depth; gradually declining upon the side of the face. Infra-orbital foramen
small and situated above the third premolar. Nasal orifice nearly as wide as
high, and situated immediately above the incisive alveolar border, as usual in
most animals. Premaxillaries and maxillaries remaining distinct from one
another. Incisive foramina of moderate size.

26 &

202

Merycocuarus.—Crowns of the molars proportionately longer than in
Oreodon, and protruding gradually as they were worn away; the anterior
having their sculptured triturating surface obliterated before the posterior are
fully protruded. Anterior premolars with the length and breadth exceeding the
width, and the upper ones inclining posteriorly, and with their points in advance
of the middle. Facial cone abruptly narrowed in advance of the orbits.
Infra-orbital arches deep and rapidly declining on the face. Orbits smaller
and more externally situated than in Oreodon. Infra-orbital foramen above
the interval of the first and second molars. Nasal orifice situated far above
the alveolar border, as in the tapir, and commencing below as an angular
notch of the premaxillaries, which are firmly co-ossified together and with
the maxillaries. Incisive foramen large.

Merrycuyus.——Teeth as in Merycocherus. Facial cone intermediate in-
character to the latter and Oreodon (?) Infra-orbital foramen situated above
the last premolar, or in a position intermediate to that of Oreodon and
Merycocheerus.

The more characteristic of the remains of Merycocheerus, from the Sweet-
water River, consist of fragments of jaws with teeth from perhaps a half
dozen individuals. One of the specimens consists of the greater part of an
upper jaw, represented in Figs. 1, 2, Plate III, accompanied with a portion
of the lower jaw, represented in Fig. 3 of the same plate.

The face of Merycocheerus, as indicated by the upper-jaw specimen just
mentioned, would appear to differ in a remarkable manner from that of the
closely allied genus Oreodon. In the species to which the name 6f Mery-
cocherus rusticus has been given, and which probably is the same as Mery-
chyus medvus, the face is narrowed in the same abrupt manner in advance of
the orbits as in Merycocherus proprius. It is, however, more convergent than
in the latter, or is proportionately less widened at the extremity. .

The relation of the orbits and zygomata to the fore part of the face in
Oreodon is more like the condition in the peccary; in Merycocherus more
like that in the hog.

The side of the face in JL rusticus between the position of the
orbit and the prominence produced by thé canine, and above the alveolar
ridge, is deeply concave, even more so proportionately than in the hog. In
M. proprius, it is not depressed in this manner, so that the side of
the face in the corresponding position is nearly vertical, and the large infra-

203

orbital foramen opens forward on this vertical surface. In MZ. rusticus, the
infra-orbital foramen is also large, and occupies a corresponding position, but
is situated in the concavity of the side of the face, so that the surface of the
alveolar border curves outwardly and downward from it.

The front of the snout or fore part of the upper jaw resembles in its con-
struction the same part in the tapir more than that of Oréodon, but, as in the
latter, it barely projects beyond the position of the canine alveoli. The pre-
maxillaries are completely co-ossified with each other and with the maxillaries.

Viewed at the side, the fore part of the upper jaw is convex forward and
downward, as in the tapir. Viewed in front, (Fig. 2, Plate IIL) it presentsa
long slope, narrow above, widening below, depressed toward the median line,
and bounded laterally by the convex curved prominences of the canine
alveoli. About 13 inches above the alveolar margin the nasal orifice com-
mences in an angular notch as in the tapir, but proportionately less narrow.

Behind the position of this nasal notch, bordered by thickened ridges
ascending in a convergent manner from the canine alveoli, are the lateral con-
cavities of the face before mentioned.

The upper part of the face being broken away, we can form no just idea
of its character. If constructed as in Oreodon, by the conjunction of the
maxillaries along the course of the nasals, it would appear to be exceedingly
narrow, even less than half the width at the alveolar border. It would appear
as if the construction might be somewhat similar to that in the tapir, so that
the maxillaries bounded a large nasal aperture overhung by the nasals.

The infra-orbital arch is nearly twice the depth it is in Oreodon, and resem-
bles in its proportions that of the hog. Its outer surface is nearly vertical or
slopes slightly outward, and is nearly plane or slightly depressed. The ante-
rior zygomatic root is an unusually prominent process of the maxillary. Its
suture of conjunction with the malar descends nearly on a line with the an-
terior border of the orbit. The latter is smaller, and is situated more exter-
nally than in Oreodon.

The roof of the month is moderately concave, and the incisive foramen,
apparently, is proportionately as large as in the tapir.

The lower jaw of Merycocheerus is like that of Oreodon, and, as in this and
all living ruminants, has the rami united by suture.

The mental foramen, like the infra-orbital foramen, is proportionately larger

than in Oreodon. Perhaps this difference in the size of the foramina, together

204

with the other peculiarities of the face, may indicate that Merycochcerus was
provided with large prehensile lips, or probably a short proboscis.

As in Oreodon, the dental series of the upper jaw consists of 3 incisors, 1
canine, 4 premolars, and 3 molars; of the lower jaw, 4 incisors, 1 canine, 3
premolars, and 3 molars.

In both jaws of Merycocheerus, as in Oreodon, the teeth form nearly closed
rows. The largest interval is between the canine and first premolar of the
upper jaw, to accommodate the lower canine, which in all the Oreodont family
occupies a position behind the upper one.

A last upper incisor, retained in the upper-jaw specimen of Merycocherus
rusticus, resembles in its form and relative size to the others the correspond-
ing tooth in Merychyus elegans.

In a fragment of a lower jaw represented in Fig. 5, Plate VII, and retain-
ing most of the incisors, the lateral one is observed to be much: larger in re-
lation with the others than in Oreodon. Its crown, viewed in front, is nearly
ovoid in outline. Its borders are acute and meet in a rounded point. The
outer surface is convex. ‘The inner surface, considerably shorter, is bounded
by a basal ridge. The intervening incisors, about half the size of the outer
one, successively but slightly decrease. Their crown is more truncate at the
summit, and the internal basal ridge is stronger. ‘The large lateral incisor is
to be viewed as a modified canine in its relation with this tooth as present in
animals usually.

The canines of Merycochcerus in all respects are like those of Oreodon.
As in this genus, the lower ones are to be viewed as modified first premolars,
assuming the form and function of canine teeth, but still holding in relation to
the other teeth the ordinary position of the former.

The crowns of the premolars of MM. rusticus in their earlier state are con-
siderably longer proportionately than those of Oreodon, and by the time they
became wholly protruded they were so much worn as to have the peculiar
construction of their-triturating surface obliterated. ;

The crowns of the upper premolars, except the last one, have a backward
inclination, successively increasing from the third to the first. The points
of these teeth occupy the anterior third of the crown in the earlier stage,
and at a late period become so advanced as to appear to form the anterior
corner of the crown. In Oreodon the corresponding teeth are nearly or quite
straight, and the summit of the crown is median, and continues so as the

205

teeth are worn away. The differences mentioned—that is to say, the back- |
ward inclination of the crowns of the premolars and the more advanced
position of their points in Merycochcerus—would appear to be due to a com-
parative shortening of the face and a less consequent space for the develop-
ment of the teeth.

The same differences which have been mentioned as existing between the
premolars of Merycocherus rusticus and Oreodon are also obvious in Mery-
’ chyus elegans. ‘The same may be said also of the third upper premolar in
_ the fossil referred to Merychyus major, except that in this the crown of the
tooth is proportionately not so long as in Merycocherus rusticus, and was less
worn when fully protruded. .

In Merycocherus rusticus the outer face of the upper premolars is convex
longitudinally, but concave transversely; the lateral borders having a consider-
able degree of, prominence. In MW. proprius and Merychyus major they are like-
' wise concave and bordered by.a strong basal ridge which is absent in Mery-.
cocherus rusticus. In Merychyus elegans the outer face of the upper pre-
molars is convex transversely as well as longitudinally, and, as in the latter, is
devoid of a basal ridge.

In a small fragment of an upper jaw of JZ. rusticus, containing the second
and third premolars, represented in Figs. 3, 4, Plate VII, the crowns are com-
paratively but little worn and retain the characters of the triturating surface.
These teeth are of less breadth in proportion to their thickness than in M.
proprius, and in this respect are more like the corresponding teeth of Oreodon.
Their outer part forms a strong curve from the ends of the fangs to the point
of the crown, of which about one-fourth externally remains unprotruded,
while it is fully protruded internally. The point of the crown is at the
anterior third, and externally it appears to be continuous as part of the an-
terior projecting border of the crown, ‘The inner portion of the crown ex-
hibits three deep recesses inclosed by prominent loop-like folds. The pos-
terior larger recess is separated from the anterior smaller pair by a ridge
dividing the inner part of the outer or principal lobe of the crown. A basal
ridge festoons the posterior internal loop of the third premolar, but does not
exist in the second. The teeth are worn off in a slope on the postero-internal
face of the principal lobe of the crown.

206

These teeth are sufficiently like the corresponding tooth in the jaw-speci-
men of Merychyus major to render it probable that this animal may belong to
the same genus as the former. ‘

The last upper premolar of Merycocherus rusticus is like that of M. pro-
prius.

The superior molars, the inferior premolars and molars, are so closely like
those of Merychyus elegans, that they may be considered as their magnified
representatives. )

Fig. 1, Plate VII, represents a series of upper molars in a specimen in
which the last one has not more than two-thirds protruded. A view of the
outer part of this last molar is introduced in the representation of the upper
jaw in Fig. 1, Plate III, so as to complete the series of upper molar teeth.
In the first molar the anterior crescentic enamel pit is observed to be com-
pletely obliterated, and the posterior one nearly so. In the back two molars
the inner faces of the internal lobes are decidedly concave longitudinally.

In Fig. 6, Plate VII, we have a presentation of the first and second
upper molars of Merycocherus proprius introduced for comparison. The
specimen is from the head-waters of the Niobrara River, in the vicinity of
Fort Laramie.

Fig. 2, of the same plate, represents the last premolar and the molar of
the temporary series of JZ. rusticus. The molar is like those of the perma-
nent set; the premolar resembles the former modified by having the anterior
lobes, especially the inner one, proportionately less well developed.

In a small fragment of an upper jaw of another young animal, in which the
temporary molars were retained and the first permanent molar had protruded,
the maxillary presents a different appearance from that in the adult. The
surfaces above and below the position of the ridge produced by the malar
process are almost at a right angle to each other. The upper surface slopes
forward and outward from the position occupied by the orbit, and upon it
opens the infra-orbital foramen about half an inch within the ridge separat-
ing this surface from the lower one. In the progress of development from
youth to age the angularity of the outer part of the maxillary became rounded,
so that the surface assumed a convex instead of a nearly rectangular char-
acter.

207

Measurements of the jaws and teeth of AZ. rusticus are as follows:

Lines.
Distance from upper incisors to back of last molar ....-.---.----...---.- 62
Length of space occupied by upper series of molar teeth ........- emekneels 53
Length of space occupied by upper premolars -.-..-.. “soe ecoce dc ensesstedec 22
imeneth of space occupied by upper molars......--.----~-<---+e.-----=-+- 31
Breadth of upper jaw outside of canines --.--.--.-.----.-+-. ----------- 22
Breadth of upper jaw outside of second premolars -.-..-- -- sme) aee 24
Breadth of upper jaw outside of second molars.......--.--. Yep RIE) 5 2 30
Breadth of upper jaw at inner side of infra-orbital foramina -.......-..--- 20
Breadth of face at lower margin of the orbits ..... ....-...---+.2...---. 55
Distance from lower incisors to back of last molar..............---+----- 62
Length of space occupied by lower series of molar teeth ...........-.--.. 48
Length of space occupied by lower premolars ..........--.---.---------- 17
Length of space occupied by lower molars .--..---..-- .----------------- 31
EMEC MOWEeL ANY Ab SYMPHYSIS. < 222. -i26- oie senda e bes esl see ee: 29
fwepinoL lower jaw below last premolar .-....-...---<-.-.s-s-s---2.--+- 19
Depth of lower jaw below second molar ...........-.--...----- he, ate 22
Pemoveron condyle’ of lower Jaw .22.5-0). 6... scat eee eb eee eee 19
Antero-
posterior. | Transverse.
Lines. Lines.
Diameter of upper canine .......-. 2s Bi ER Eee ee aE 43 43
DAME TOROMOW EL: CANINE wo. )2 5 210-\c com acses doce camnn ya eaecne- 5 44
Diameter of second upper premolar........-.--..----.+-- 54 4
rameter ot third upper premolar............--+...0-.....-.- 6 a
Diameter of fourth upper premolar.........-...-..-.--02-.-. 5 64
Diameter of first upper molar...-.... ........----.. Bee aad 84 83
Miameter of second upper molar ........:.--...------.-+----: 11-12 10-104
Memmerer OF third uppermolar,....- 2-2-2. senee. Dee e le 14 103
Mramecer of first lower premolar.......-.--.-.-- --.-- -t-.- 5 23
Diameter of second lower premolar .....-.--....--.+---+---+. 6 44
Wermmeter of third lower premolar.......¢..-....2-- 2-2 '.-4-- 65 5
Diameter of first lower molar.......--.......----- Ey Sod bane 7 6
Dime rerioh second lower MOlAN .- sc 2 oes eecc ce weet ee eee 10 74
Diameter of third lower molar......-..:.----..--.2s2-.02-5- 153 7

Of other bones referable to Merycocherus rusticus, the collection contains

the following:

Portions of several scapule. The glenoid cavity is oval, and measures 11
lines in its short diameter, and 15 lines in its long diameter, including the

coracoid process.

208

A number of fragments, mostly distal extremities of tibize, of which one is
represented in Fig. 9, Plate XX. The general construction is the same as
in ordinary even-toed ungulates. The shaft approaching the articulation is
three-sided, with the outer border subacute. This terminates in a triangular
surface for junction with a fibula. The internal malleolus is comparatively
long and pointed, and projects below the position of the anterior process of
the tibia. The articular concavities are nearly of the same extent fore and
aft, but the outer one is much the wider. The width of the end of the tibia ©
in different specimens ranges from 13 to 14 lines, and the fore and aft diam-
eter is 84 lines.

Of a number of specimens of the astragalus, one is represented in Fig. 10,
Plate XX. It is about the size of that of the peccary, but is proportionately
wider. The outer division of the trochlea is considerably larger than the
inner one. The posterior articular surface for the calcaneum extends but
little more than half the width of the bone. The length of the astragalus
externally is 16 lines; its width at the lower tarsal articulation is 104 lines,

Of a number of specimens of the. calcaneum, one is represented in Fig. 11.
It is about the size of those of the peccary, but is more robust in its propor-
tions. The tuber is a little shorter, but considerably thicker. A peculiarity
of the bone is the absence of a sustentaculum tali, the usual articular surface
of the latter being supported on a moderate expansion of the base of the
tuber. The articular eminence for the fibula is but slightly prominent.

The length of the calcaneum is Di inches; its width at the articulation
below the tuber is 8 lines. .

Another specimen of a calcaneum, interesting on account of its diseased
condition, is represented in Fig. 15, Plate IT.

MeErRyYcocHa@rus

Fig. 12, Plate XX, represents the distal end of the tibia, probably of a
smaller species of Merycocherus. The specimen was found with those

sp ?

above described. The transverse diameter of the articular end is 11 lines.
An astragalus resembling that above described probably belongs to the
same animal as the latter. It is 104 lines long, and 54 lines wide.

Order Solidungula.

Associated with the remains of Merycocherus, from the Sweetwater
River, there are several bones of a small equine animal, probably a species

209

of Hipparion. One of the specimens is an external cuneiform bone, of which
an upper view is given in Fig. 13, Plate XX. Another specimen of the same
bone has the navicular bone co-ossified with it. A third specimen consists
of a first ungual phalanx 17 lines long at the side, and 144 lines wide at the

upper extremity.
27 G

DESCRIPTION OF VERTEBRATE FOSSILS FROM THE TERTIARY
FORMATION OF JOHN DAY’S RIVER, OREGON.

‘Through the Smithsonian Institution, at the suggestion of Professor S. F.
Baird, a collection of fossils was submitted to the examination of the writer
by Rev. Thomas Condon, of Dalles City, Oregon.

The fossils were discovered by Mr. Condon mainly in the valley of Bridge
Creek, a tributary of John Day’s River, one of the branches of the Columbia
River. Some additional fossils from the same locality were also placed in my
hands by Professor H. 8. Osborn, of La Fayette College, Easton, Pennsyl-
vania. .

With the exception of a single turtle-bone, the fossils consist of remains of
mammals. In general appearance and condition of preservation they resemble
those of the Mauvaises Terres of White River, Dakota. They are nearly all
specimens which have been found lying loose on the surface of the country,
and are, therefore, more or less weathered, or much injured by exposure. A
few of the fossils are imbedded in, and the cavities of others are filled with,
a hard, compact, homogeneous rock of a bluish-gray hue. The rock appears
to be an indurated marl, and contains abundance of lime. It bears @ near
resemblance to the matrix of the fossils of the Mauvaises Terres of Dakota,
except that it is more compact and harder.

The zoological character of the fossils is such as to render it probable that
the formation to which they belong is of contemporaneous age with the Ter-
tiary deposit of the locality just named.

The greater number pertain to a species of Oreodon larger than any of
those from White River, Dakota, and about the size of Merycochwrus proprius
of the Niobrara River, Nebraska.

A number of the fossils appear to belong to some of the same species as
those of the Mauvaises Terres, as Oreodon Culbertsoni, Agriocherus antiquus,
and A. latifrons, Leptomeryx Evansi, Anchitherium Bairdi, and Rhinoceros
occidentalis.

The collections further contain remains of a second species of Rhinoceros,
two species of Elotherium, &c., generally too scanty or imperfect to ascertain
positively whether they pertain to species previously characterized

att

A descriptive list of the fossils is given below :

MAMMALIA.

Order Ruminantia.

OREODON.

OREODON CULBERTSONI.

This species, established on a multitude of remains from the Mauvaises
Terres of White River, Dakota, is apparently indicated by some small frag-
ments of upper and lower jaws with teeth, which are labeled ‘“ Big Bottom
of John Day’s River.” One of the best-preserved and most characteristic
specimens consists of a jaw-fragment containing the upper last premolar
and the molars, the latter being represented in Fig. 12, Plate VII. In all
respects it is like the corresponding part in Oreodon Culbertsoni, from White
River. Other specimens show a slight variation in the size of the teeth.

OREODON SUPERBUS.

Nearly twenty-five years have elapsed since the first fossil remains of

mammals from the Tertiary formations of the West were submitted to my
examination. ‘To the present time they have been coming to me in constant
succession, so that I have had the opportunity of examining thousands of
specimens, the collective weight of which would amount to several tons.
From some of the first specimens brought from the Mauvaises Terres of
White River, Dakota, after a few errors, I thought I had fixed upon well-
marked characters distinguishing the extinct genus of hog-like ruminants, for
which I proposed the name of Oreodon. Two species were described under
the names of O. Culbertsoni and O. gracilis, mainly from a marked difference
in size.
_ Several detached crania, differing from that of either of the species of Oreo-
don in the possession of large inflated ear-capsules, at first attributed to a
peculiar genus with the name of Eucrotaphus, were subsequently referred to
Agriochcerus, which had originaily been described from jaws and teeth. Later
this determination appeared to be confirmed by an almost complete skull in
which the cranium agreed with the detached specimens.

Some small fragments, and finally a complete skull, appeared to indicate a

third and larger species of Oreodon, to which the name of O. major was given.

212

It is especially remarkable for the great size of the ear-capsules compared
with those of the other species, being proportionately quite as large as those
in Agriocheerus.

Of the multitude of fragments of jaws with teeth, portions of skulls, and
more or less complete skulls of Oreodon, which I have had the opportunity of
examining, by far the greater number are referable to the species O. Culbertsoni, -
about a twentieth to O. gracilis, and one per centum to O. mgor. Specimens
exhibit more or less variation, generally of a comparatively trifling character,
but in some instances to such a degree as nearly to be distinctive enough for
other species, and in some cases as nearly to remove the distinctions between
the two species O. Culbertsoni and O. gracilis. 'Two specimens, presenting a
greater extent of variation than usual, have been suspected to represent hybrids
in the one case between O. Culbertsoniand O. gracilis, in the other case between
the former and O. magor. With the view that they may be specifically dis-
tinct, they have been named O. affinis and O. hybridus.

After a number of years, and after having seen many hundred specimens
referable to O. Culbertsoni, to my utter astonishment one of the last ones
received, consisting of the greater part of a skull, while agreeing in every
other respect with the ordinary form of O. Cudlbertsoni, possesses ear-capsules
as large as those of Agriochcerus. Looking upon this specimen as represent-
ing a species or an important variety, the name of O. budlatus was applied to
it in allusion to its large inflated ear-capsules.

As the cranial portion of the skull of O. bud/atus does not differ in size from
the specimens originally referred to Eucrotaphus, we are now uncertain
whether they pertained to O. bullatus or Agriochcerus. They correlate in
size, construction, and form equally well with either.

Some remains from the Niobrara River, Nebraska, while clearly indicating
members of the same family as Oreodon, appeared to me te belong to two
different genera, to which the names of Merycocherus and Merychyus were
given. The recent discovery of additional remains of another species of
Merycocheerus, on the Sweetwater River, Wyoming, while rendering the
characters of the genus more obvious, rather tend to make the genus Mery-
chyus doubtful.

The skull of Merycochcerus has the same general form and construction as
that of Oreodon, and the teeth agree in number, relative position, and consti-
tution. The crowns of the molar teeth in Oreodon are short and inserted by

213

fangs, as in the deer. In Merycochcerus they are longer, and protrude more
gradually as they are worn away. The face is more abruptly prolonged in
front of the orbits; the infra-orbital arches are proportionately of much greater
depth; and the infra-orbital foramina situated much further back. While the
fore part of the upper jaw of Oreodon is constructed in the more ordinary
manner of many animals—suilline pachyderms, carnivora, &c.—that of Mery-
cocheerus is more like that of the tapir.

Merychyus, so far as known, is intermediate in character with Oreodon and
Merycocherus. Its molar teeth are like those of the latter; its face appears
not to be so abruptly narrowed; and the infra-orbital foramina hold an inter-
mediate position. é

Another member of the oreodont family, from a formation probably of
equivalent age to that which has yielded the remains of the Oreodons, has been
named Leptauchenia. Its molar teeth agree in character with those of Mery-
cocheerus and Merychyus, but are more strongly folded internally in the case
of the lower ones, externally in the case of the upper ones. The face is more
like that of Oreodon ; has the infra-orbital foramina in the same relative posi-
tion, but has large unossified spaces at the upper part of the face.

Oreodon, superbus, the name which appears at the head of this chapter, was
applied to a species, indicated more recently than any of the preceding, from
specimens belonging to Mr. Condon’s collection of Oregon fossils. The species
exhibits characters which make it somewhat peculiar, and place it in a position
intermediate to the White River Oreodons and the genus Merycocheerus. It
is exemplified by a number of specimens, among which is the mutilated skull,
represented, one-half the natural size, in Fig. 1, Plate I. Other specimens,
consisting of detached mutilated crania, portions of others, and fragments of
jaws and teeth, pertain to half a dozen or more individuals.

The .skull of Oreodon superbus is about the size of that of Merycochwrus
proprius. In form, proportions, and constitution, and in the number, relative
position, and construction of the teeth, it nearly resembles the other known
species of the genus from the Mauvaises Terres of White River, Dakota.

The cranium proper is a magnified likeness of that of Oreodon Culbertsoni
or O. major, and more especially agrees with the latter in the possession of
large inflated ear-capsules. It presents the same kind of variation in different
specimens observed in O. Cudbertsont. In most of the specimens the tempo-

ral surfaces slope from the sagittal crest with a slight sigmoid curve. In one

214

specimen the parictal surface is deeply depressed on each side of the sagittal
crest. In another specimen a pair of well-marked grooves follow the course of
the fore part of the squamous suture, one in front, the other behind it. In all
the specimens the front groove is more or less distinct; in some of them the
back groove is barely perceptible. |

The auditory capsules are ovoidal, with the greater diameter fore and ait,
and the length exceeding the width. They extend from the paramastoid
process forward to the middle line of the glenoid articular surface, and project —
below the level of this for half their length.

The face of Oreodon superbus differs from that of the other species of the
genus more than it does among these. It especially differs in the position of
the infra-orbital foramen, and in the great proportionate depth of the infra-
orbital arch. In the other known species of Oreodon the infra-orbital fora-
men occupies a position above the third premolar. In O. superbus it is placed
above the last premolar, as in Merychyus. In Merycocheerus it is placed fur-
ther back over the interval of the first and second true molars. The infra-
orbital arch is proportionately as deep as in Merycocheerus, and like it presents
a broad, nearly flat surface, extending forward below the position of the lach-
rymal fossa. The latter is relatively shallow. ‘The forehead is more flat than
is usual in Oreodon Culbertsoni. 'The anterior nasal orifice is like that in other
species of the genus.

The teeth of Oreodon superbus, so far as we have had the opportunity of
examining them, appear to agree in all respects with those of the other known
species.

Fig. 16, Plate II, represents a fragment of the lower jaw, natural size, con-
taining the premolars and the first molar. A view of the triturating surfaces
of the premolars is given in Fig. 9, Plate VII.

Figs. 7, 8, Plate VII, represent a first molar, part of the second, and the
last molar from a lower-jaw specimen.

Fig. 10, of the same plate, represents a facial specimen, with a view of the
forehead, one-half the natural size. |

Measurements obtained from several specimens of portions of skulls of

Oreodon superbus arc as follows:

Estimated length of skull, approximating 14 inches.

215

Lines. | Lines. |} Lines.

Breadth of forehead between orbits on line with supra-orbital
Ore ADDU Nal eee erat sit 3 ade! ep Saree Mechs grees wichnara nN eSA Liat ihre tar Eb pee DOM es. 50
Length of face from orbit to lateral nasal notch........-.....-.. AMA aerial fate
' Height of face on line with the second true molar.....-...-..-- Ee Seana enc | oo ic
DepuMrok Orpital entrance. 2229. hese sce. cs eae Se oes ee one Zi hehe esta eae ees
Mransverse diameter of the same «......------.22:0 25-201 se eee: WO es 2 fe 2 a
Wepihvok intra-orbifalvarchie: 2.2 25.22. diasc 2 oF. new ope we (ae 18 2:1 laa eae ore
Length of upper molar series, estimated at........--. .-------- TD oA ee Re ee
Antero-posterior diameter of last upper molar ........----.-..--|.----. BG ees
Transverse diameter of last upper molar ....-...-....-..--.----|.---.- 1S al ee ee
eam iNKOn MASAISMPOSCPNEL. . 242% cals <a. So coe = vie alee doe ona wee fewer ee eles cee 16

Measurements obtained from lower-jaw fragments detached and not per-

taining to the preceding :

Lines. | Lines. | Lines. | Lines.
Space occupied by the lower molar series ...”........-.--- SAG Ge pois ae eat Ee ea
Space occupied by the lower premolars.....-......-...-. EAT RC lappa 303 | 273
Space oceupied by the lower molars.......-..........--. 40 0 gana Re ea ee
Depth of jaw below back of last molar...........-..-.--.]..-. SOE ESO Seats eaten ape
Depth of jaw below fore part of last molar.........-..... 27 DG Verena crccat es sae ;
Depth of jaw below middle of first molar ...........----. 25 tl tcl 3
Depth of jaw below middle of second premolar ......-.-..-- HES gee | ee 31
Antero-posterior diameter of first-premolar ..........-.--|......|...... LT Ve
Transverse diameter of.first premolar .........-..-.....-/.-----|....-. at ees
Antero-posterior diameter of second premolar......-..--./..-- Bia a's LOr eet
Transverse diameter of second premolar......-.....-.--.|......| ....! 44 |......
Antero-posterior diameter of third premolar .......-...-./.....-|...... MAT lave Ps
Transverse diameter of third premolar ............-.----|--.-.2|-..... Pe ieee
Antero-posterior diameter of first molar...........-...--.|...-.. (1) fie ees Sy eee
iMansverse diameter of first molar .....20-.-...25....0.-.{.--2.- OAS aie tea ai
Antero-posterior diameter of second molar........-...---{.....- TOE a ees et ae
Transverse diameter of second molar..-......--..-.-----|---.-. Sa tee eee ea torte
Antero-posterior diameter of third molar .-.........-..-.|--..-. 1h reo ees (ee
Mransverse diameter of third molar ...................--|....-. DS Stee east I
Transverse diameter crown of lower canine .........--.--|.....-[...-..|--.--. 11

216

LEPTOMERYX.

LepromMeryx Evansi.

A small ruminant, related to the musks, was originally described under the
above name, from remains discovered by Dr. John Evans and Professor Hay-
den in the Mauvaises Terres of White River, Dakota.

Two small fragments of jaws, the one containing a well-preserved upper
molar and the other a lower molar, from John Day’s River, agree in all re-
spects with the corresponding parts of Leptomeryx Evansi. |

AGRIOCHGERUS.
AGRIOCHGRUS ANTIQUUS. AGRIOCH@RUS LATIFRONS.

The above genus and species were originally characterized from remains
found in the Mauvaises Terres of Dakota. The genus is related with Oreodon,
but exhibits peculiarities enough to regard it as pertaining to another family
of extinct ruminating hog-like animals.

A small fragment of an upper jaw with portion of a molar, and a few frag-
ments of detached molars from John Day’s River, appear to indicate the
presence of both the above-mentioned species.

Artiodactyla.

DIC OTYLES.
DicoTyLEs PRISTINUS.

An extinct animal about the size of and nearly allied to the living collared
peceary, Dicotyles torquatus, .is represented in the Condon collection by
several detached lower molar teeth. ‘These have nearly the size and consti-
tution of those of the collared peccary, though considerably worn and there-
fore smoother than when in a younger condition. Independently of this
smoothness, due to age, the constituent lobes of their crowns do not present
the wrinkled condition observed in the living peccaries.

The last lower molar, represented in Fig. 14, Plate VII, has a five-lobed
crown with a basal ridge in front and externally, and also postero-internally.
The lobes of the crown are comparatively simple, or but slightly complicated
by offsets or folds. The penultimate molar, represented in Fig. 13, Plate VIL
has four principal lobes to the crown, arranged as in the recent peccary.

An upper molar, from a younger animal, perhaps, belonged to the same

217

species. It is more square than in the recent peccary, and has the four con-
stituent lobes of the crown comparatively smooth and devoid of wrinkles.
Measurements of the specimens referred to Dicotyles pristinus are as fol-

lows:
‘ 5 : Lines
- Antero-posterior diameter of last lower molar ........-.......---.-----:------- 9
Miransverse: diameter of last lower molar iiss .262 022-5 esses Sense eee sev cis oes 5
Antero-posterior diameter of penultimate lower molar.-......-.....----.---.--- i
Transverse diameter of penultimate lower molar. .....-..--.- JGb US hoes ae eee 54
Antero-posterior diameter of first or second upper molar .-.-..-....-.----.----- 6
Transverse diameter of first or second upper molar ........-...----.----------- 54

Professor O. C.. Marsh has also described some remains of peccaries from
the same locality, which he attributes to two species under the names of
Dicotyles hesperius and Platygonus Condoni. The former is estimated as about
half the bulk of the collared peccary, the latter as being about the size of
the hog.

ELOTHERIUM.
ELOTHERIUM IMPERATOR.

Mr. Condon’s collection of Oregon fossils contains portions of several teeth
of large size, which are supposed to belong to a huge species of Elotherium,
for which the above name is proposed.

One of the specimens, represented in Fig. 3, Plate II, is a portion of a
large canine tooth, from Bridge Creek. In the perfect condition the tooth
would appear to have measured upward of 7 inches in length. The crown
has measured about 33 inches long, with the diameter at base antero-posteriorly
about 22 lines, and transversely about 20 lines. The enamel is moderately
rugose, except near the back border of the crown, where it exhibits a more
folded or ridged appearance. The gibbous fang has been over 4 inches in
length, with the fore and aft diameter about 2 inches and the transverse
diameter 20 lines.

Another mutilated specimen, from Bridge Creek, supposed to be an upper
incisor, is represented in Fig. 27, Plate VII. When complete, the tooth has
measured over 4 inches in length. The fang is:long, conical, and nearly
straight. The crown forms with its fang an obtuse bend or angle. It is
conical, compressed from without inwardly, and has the lateral borders sub-
acute and somewhat expanded toward the base.

28 G

218

A third specimen, from John Day’s River, represented in Fig. 4, Plate I,
consists of the greater portion of the crown of an anterior premolar. It is
blunted at the apex as the result of wear. When perfect and unworn it has
measured about 14 inches in length, about 16 lines antero-posteriorly, and
about 94 lines in thickness.

It is not improbable that part or the whole of the specimens pertain to the
species named Llotherium superbum, from an isolated incisor tooth found in
Calaveras County, California, in the same formation in which was discovered
the specimen of a lower jaw referred to Rhinoceros hesperius.

Solidungula.

ANCHITHERIUM.

ANCHITHERIUM BaAtRDI.

The extinct genus of solidungulate animals, Anchitherium, was. originally
described from remains found in the middle Tertiary formation of France.
Abundant remains of a species have also been found in the Mauvaises Terres
of White River, Dakota, which have been described under the name of
Anchitherium Bairdi. The Condon collection contains several specimens,
consisting of detached molars and fragments of others, apparently of the
same species. One of the best preserved of these, the crown of an upper
molar, is represented in Fig. 15, Plate VIL In every respéct it agrees with
the upper molars of the Anchitherium Baird: of White River.

ANCHITHERIUM CoNDONI.

A specimen in the Oregon collection of fossils, consisting of a smatl jaw-
fragment with a mutilated molar, represented in Fig. 5, Plate Il, I have
referred to a species of Anchitherium, though several points lead me to sus-
pect that it may belong to a different though closely allied genus. The gen-
eral form and construction of the teeth are the same as in A. aurelianense and .
A. Baird. The intermediate lobes of the crown are proportionately larger,
more distinct from the others, and more prominent than in the species just
mentioned. A tubercle springing from the basal ridge between the antero-
internal and antero-median lobes is obsolete in the true Anchitherium.

The diameter of the crown in both directions is about three-fourths of an
inch. The species was named in compliment to the Rev. Thomas Condon,

219

through whose interest in natural history. most of the Oregon fossils have been
brought to the notice of the world.

Perissodactyla.
LOPHIODON?

Among the fossils from Bridge Creek, in the Condon collection, there is a
small fragment of an upper jaw containing two molar teeth, represented in*
Fig. 1, Plate IJ, which probably indicates a tapiroid animal, allied if not
actually pertaining to the extinct genus Lophiodon. The teeth, which appear
to be the upper back premolars, are much worn, and the last one is mutilated.
' They belonged to an animal about the size of the common American tapir,
(Tapirus terrestris.)

The teeth nearly resemble the corresponding ones, as we might suppose
them to be in the same state of wear, of Lophiodon isselense, of the Eocene
formation of France, as represented in Gervais’s Plate XVIII, of the Zoologie
et Paléontologie francaises; or they would appear to bear a nearer resem-
blance to those of Palg@osyops paludosus of the Bridger Tertiary formation of
Wyoming. 3

The teeth are inserted with three fangs, two externally and a broader one
internally. ‘The crowns are widest transversely, square without, semicircular
- within. ‘They are composed of a pair of pyramidal lobes externally and an
internal median conical lobe embraced by a thick basal ridge. The antero-
external lobe extends in a ridge to the fore part of the base of the inner lobe,
and the postero-external lobe appears to have been continuous by a ridge
with the base of the inner lobe. A thin basal ridge festoons the outer part
of the crown. .

In the worn condition of the teeth they present a wide tract of dentine
continuously on the outer lobes. In the penultimate premolar the tract ex-
tends inwardly from the postero-external lobe on the inner lobe, and from
the antero-external lobe to the base of the latter in front. In the last pre-
molar the dentinal surface of the outer lobes extends continuously on the
inner lobe. ,

The penultimate premolar measures 84 lines antero-posteriorly, and 114
lines transversely; the last premolar measured about 10 lines antero-poste-
riorly, 11 lines transversely.

The size of the specimen, and its apparent relationship with Lophiodon,

220

led me to suspect that it might pertain to the same animal as an isolated
molar tooth, from the Mauvaises Terres of White River, Dakota, described
under the name of Lophiodon occidentalis.

RHINOCEROS.

A nuimber of fossils in the Oregon collection appear to indicate two differ-
-ent species of Rhinoceros, or perhaps the hornless form Aceratherium. One
of them was about the size of the Rhinoceros occidentalis of the Tertiary of
the Mauvaises Terres of White River, Dakota, and was first supposed to
belong to that species. A more attentive examination of its remains has led
to the detection of several peculiarities which render it probable it may be a
distinct species. As the specimens co-ordinate in size with the lower jaw
‘from the California Tertiary, on which was founded the LR. hesperius, they
may perhaps pertain to this species; and in this view I will so consider them.
Of course, more ample material may confirm or refute our position, and may
determine the fossils to indicate an animal different from I. occidentalis and
R. hesperius.

The second species, a larger animal, intermediate in size to the latter ones,
and the &. crassus of the Niobrara Pliocene Tertiary, has been distinguished

with the name of R. pacificus.
RHINOCEROS HESPERIUS 2

The fossils of the Condon collection, attributed with some probability to
this species, consist of a mutilated portion of an upper jaw an isolated upper
molar, and a lower-jaw fragment containing one entire molar. |

The upper-jaw specimen contains portions of the fangs of the molars, of
which there were seven, occupying a space of about 74 inches, or about
equal to that in Rhinoceros occidentalis.

The anterior extremity of the space included by the zygoma.extends to a
line with the interval of the second and third molars; in &. occidentalis it
extends only to a line with the back part of the last molar.

The infra-orbital foramen is large, and occupies a position above the second
premolar; in R. occzdentahs it is over the third premolar.

The upper molar, the last of the series, represented in Fig. 8, Plate II, has
nearly the size and form of that.of J. occidentalis. As in this, the crown

consists of a pair of lobes diverging inward from the antero-external corner.

221

A strong bulge projects from the middle of the anterior lobe into the valley
of the crown, which is not so well developed in J. occidentalis, and a second
bulge at the bottom of the valley is absent in the latter. The basal ridge is
stronger in front, and internally at the entrance of the valley of the crown it
forms two conspicuous, rounded tubercles not seen in a corresponding posi-
tion in ft. occidentalis. 'The presence of these tubercles, however, is, perhaps,
merely an individual peculiarity. The tooth measures 15 lines antero-poste-
riorly and internally, and is estimated to have been 19 lines transversely.

The lower-jaw fragment, containing a molar, represented in Fig. 9, Plate
II, exhibits nothing peculiar distinguishing it from the corresponding part
either of R. occidentalis or R. hesperius.

RHINOCEROS PACIFICUS.

The fossil specimens indicative of the second species of rhinoceros from
the Oregon Tertiary consist of a mutilated right side of the upper jaw with
portions of fangs of the.molars, except of the first premolar, and several iso-
lated molar teeth.

The specimens indicate a species larger than the preceding, but not reach-
ing Rhinoceros crassus of the Niobrara Tertiary, which was about the size of
the existing India rhinoceros.

The upper-jaw specimen retains portions of the fangs of six molar teeth,
counting from behind. The space occupied by the back two premolars and
the-molars is estimated at nearly 74 inches; that occupied by the true molars
at rather more than 5 inches.

The fore part of the zygomatic space is on a line with the fore part of the
last molar tooth.

_ Fig. 6, Plate Il, represents an upper molar which is supposed to belong to
this species. The specimen is broken at its back part, and is labeled “Alkali
Flat.” The crown at the fore part measures 21 lines in diameter, and is esti-
mated to have measured 14 inches antero-posteriorly. ‘The bottom of the
crown is embraced with a strong basal ridge, which is strongest anteriorly
and internally. The inner lobes expand inwardly, but do not bulge in the
abrupt manner posteriorly to the same degree that they do in R. occidentalis.
The bottom of the oblique valley of the crown is expanded, and is compli-
cated by the projection into it of four folds.

Another tooth, represented in Fig. 7, Plate II, likewise labeled ‘ Alkali

222

Flat,” has the appearance in condition of preservation, color, and wear, as if
it might have pertained to the same individual as the former specimen. If
so, it is related to it apparently as the last premolar to the first molar. The
antero-posterior diameter of the crown is nearly 16 lines; the transverse
diameter is 19 lines. The basal ridge and inner lobes are as in the former
tooth. Traces at the bottom of the oblique valley appear to indicate a dispo-
sition to the formation of two folds like those existing in the same position in
the larger tooth.

It is not unlikely that this second molar tooth may be a true molar of the
preceding species. ’

The crown of a lower molar tooth, represented in Figs. 24, 25, Plate VII,
from Bridge Creek, is supposed to belong to R. pacificus. It measures 20
lines fore and aft, and 1 inch transversely, at base.

HADROHYUS.
HADROHYUS SUPREMUS.

Among the Condon collection of Oregon fossils there are several, apparently
of a large pachyderm, differing from those previously indicated, and likewise
different in character from such as have been heretofore described.

Fig. 26, Plate XVII, represents a fragment of a tooth which I have sup-
posed to be a last upper premolar. The crown of the tooth would appear in
its entire condition to have nearly the form and construction of the corre-
sponding tooth of the Oreodonts, but differs especially in the proportionately
less degree of development of the inner lobe and the greater degree of pro-
duction of the inner basal ridge. ‘The remains of the inner lobe have the
appearance of being composed of a nearly connate pair, which no doubt
would be found better developed and more distinct in the succeeding teeth.
In the specimen the inner lobe appears notched, and the dentine is exposed
on the outer lobe and the anterior division of the inner lobe.

The transverse diameter of the specimen is 1$ inches. The tooth is

labeled ‘‘Alkali Flats,” and may be regarded as BEUESSCHIINE the animal to
which the above name is given.

Another specimen pertaining to an animal as ie as that to which the
tooth just described belonged, and perhaps actually belongimg to the same,
consists of a brain-cast, or rather the cast of the interior of a cranium. The
cast has nearly the size and shape of the brain of a horse. The cerebral

223

hemispheres are nearly as much convoluted as in the latter, and measure
about 44 inches in length and breadth.

A third specimen, which may likewise be suspected as belonging to Had-
rohyus, is a large atlas, which measures 5 inches in width between the outer
acute borders of the articular cups for the occipital condyles, and about. 44
inches from the neural tubercle to the hypapophysis. ‘The vertebra differs in
several important points from the atlas of the rhinoceros, horse, ox, &c., but
the want of the requisite means of comparison prevents me from determin-

ing its nearer relationship.

e

AN UNDETERMINED CARNIVORE.

A supposed carnivorous animal of large size is indicated by the portion of
‘a large canine tooth, represented in Fig. 26, Plate VII. The specimen per-
tains to the Condon collection of Oregon fossils.

CHELONIA.
Testudinida.

STYLEMYS.

The extinct genus of turtles above named, and originally described from
remains found in the Miocene Tertiary formation of the Mauvaises Terres of
White River, Dakota, was most nearly related with the existing land-tortoises.
The shell is of the simplest form, and is about as prominent as in the less
vaulted forms of the living species of Testudo, or the more vaulted ones of
the terrapenes. The proportions nearly accord with those of our southern
gopher, but the carapace is more uniformly convex.

The carapace is most prominent just back of the middle, and is abruptly
rounded posteriorly as usual in the tortoises. The margin is entire, feebly
emarginate in front, somewhat expanded and everted over the axillary spaces,
and in a less degree everted over the inguinal spaces.

The plastron holds the ordinary proportions to.the carapace as in Testudo
and Emys. It is for the most part flat, and only moderately turned up in
front. The extremities are nearly equal and rounded. The anterior is
slightly narrowed; the posterior is moderately notched.

The number, shape, and relations of the bones of the shell are nearly the
same as in Testudo and Emys. The number of the vertebral plates is ten,
occasionally eleven, from subdivision of the usual eighth plate.

224

The ninth plate appears like a corresponding pair of costal plates connate
in the median line. The tenth plate is lozenge-shaped, and occupies a
similar shaped interval of the ninth vertebral and the pygal plates.

The eight pairs of costal plates in their alternate narrowing and widening
toward the extremities resemble those of the living tortoises, though the
variation is not so great as usual in these.

The interior of the vertebral plates of Stylemys exhibits a deep, narrow,
keel-like ridge, as represented in Fig. 6, Plate III, and Fig. 9, Plate XIX, in-
tended for union with the neural arches of the vertebrae. A similar con-
dition exists in the Gallipagos and other living tortoises.

The costal capituli, as seen in Fig. 6, Plate III, and Fig. 9, Plate XIX,
are feebly developed as in most species of Testudo, but are not reduced to
the rudimental condition observed in our gopher.

The first pair are as well developed as usual. The sixth and seventh pairs
unite with processes of the corresponding vertebral plates. The eighth and
ninth pairs, better developed than those in advance, unite in the root of the
process of the eighth costal plate for the attachment of the pelvis. ©

‘The scutes of both the carapace and plastron of Stylemys correspond with
those of Testudo. The pygal scute is single as in all living tortoises, except
Manouria. The pectoral scutes are very narrow, as usual in Testudo.

The thickness and strength of the shell of Stylemys is greater than ordi-
narily in the latter, but proportionately not more so than in several living
species.

The bones of the limbs, so far as we are acquainted with them, approach
in character those of the tortoises. The concavity above the articular surface
of the distal extremity of the humerus, but especially of the femur, is deeper
than in the living forms.

The remains of Stylemys are apparently referable to three species, all
geographically and perhaps geologically separated.

STYLEMYS NEBRASCENSIS.

The remains of this species form one of the most abundant fossils of the
Miocene Tertiary deposit of the Mauvaises Terres of White River, Dakota.
A multitude of specimens of nearly entire shells have been collected by all
explorers of the locality in which they are found. They present a great

225

variety of age, size, and condition of «preservation. Many exhibit in their
distortion evidences of considerable pressure, while others are so well pre-
served as to appear entirely unbroken. Their varied conditions, added to
slight anatomical variation, led me at first to attribute them to five different
species, which I now view as one.

Mature specimens are comparatively rare, at least in an entire condition
One, broken into two pieces, is represented in Plate XXIII of “The Ancient.
Fauna of Nebraska.” A second, more complete, was obtained by Professor
Hayden for the Academy of Natural Sciences of Philadelphia.

Very few other bones of Stylemys nebrascensis, other than those of the
shell, have come under my notice. Among hundreds of shells and fragments
of others, I never met with any portions of the skull or jaws.

Fig. 10, Plate XIX, represents a fragment of the scapula with part of its
precoracoid. It agrees with the corresponding portion of the bone in Testudo.

Fig. 7, of the same plate, represents the distal extremity of a humerus of
a young individual. The hollow above the articular surface is rather deeper

than in Testudo.
STYLEMYS NIOBRARENSIS.

Numerous fragments of shells and a few portions of other bones of a
second species of Stylemys. were discovered by Professor Hayden in the
Pliocene sands of the Niobrara River in the year 1857. All the anatomical
characters of the specimens indicate the same genus as the former, but
several of them point to a different species. It was about the same size as
the S. nebrascensis.

Fig. 4, Plate III, represents the anterior portion of a plastron of the
natural size, and therefore supposed to have belonged to a young animal. The
episternals are more prominent forward than in S. nebrascensis, and they are
deeply excavated beneath the broad scute-covered margin, which is not the
case in the species just named.

Fig. 5 represents the last vertebral and the pygal .plates of an
older animal. It shows that the investing scute is single, as in Testudo. The
lower margin of the pygal bone is slightly but decidedly everted, which is
not the case in S. nebrascensis.

Fig. 6 represents an inner view of a portion of a carapace one-half the
natural size. It belonged to a mature animal, and is the most complete por-

29 G

226

tion of the shell of the species whieh has been submitted to me. It com-
prises the vertebral plates from the sixth to the ninth inclusive, and portions
of the corresponding costal plates on each side. The narrow character of the
costal capitula is observable in the sixth and seventh pairs; and the two suc-
ceeding pairs are observable as they spring from the strong process for the
attachment of the pelvis. .
Fig.8, Plate XIX, represents the distal extremity of a right humerus, and
Fig. 6 the same part of a left femur, both half the natural size. The femur
would appear to have belonged to a larger animal than the humerus. The
concavity above the articular surface is much deeper than in other known
turtles, The breadth of the femur, at the condyloid eminences, is 32 lines;
that of the humerus, in a corresponding position, has been nearly the same.

STYLEMYS OREGONENSIS.

An isolated vetebral plate, im the Condon collection of Oregon fossils, is
supposed to indicate a third species of Stylemys. ‘The specimen was found
on Crooked River, and is represented, one-half the natural size, in Fig. 10,
Plate XV. It exhibits a transverse groove defining two vertebral scute areas,
and on the interior a narrow crest for union with the corresponding neural
arch. The plate appears to be the third of the series, and is thicker in pro-
portion with its length and breadth than would appear to be the case in the
preceding species of Stylemys. The specimen is 2 inches wide, 14 inches

oa

long, and 7 lines thick.

DESCRIPTIONS OF REMAINS OF VERTEBRATA FROM TERTIARY
FORMATIONS OF DIFFERENT STATES AND TERRITORIES
WEST OF THE MISSISSIPPI RIVER. | -

The fossil remains described in the succeeding pages consist mainly of
isolated specimens obtained from Tertiary formations in various parts of the
country west of the Mississippi River. They are nearly all remains of mam-
mals. Included in the series there are descriptions of a few other Tertiary
mammalian fossils, from the country east of the Mississippi, described on
‘account of their relation with the former, and for the most part for the first

. time.
MAMMALIA.
Order Carnivora.
FELIS.
FELIS AUGUSTUS.

Several teeth in fragments of jaws, and portions of other teeth, indicate a
species of tiger apparently different from any previously described. The
specimens were discovered by Professor Hayden, during Warren’s expedition
of 1857, on the Loup Fork of the Niobrara River, Nebraska. They belong
to the Pliocene Tertiary formation, and were found in association with remains
of Mastodon mirificus, Merychyus elegans, Procamelus occidentalis, &c.

The most characteristic of the specimens, represented in Fig. 19, Plate VIJ,
is an upper sectorial molar contained in a small jaw-fragment. The tooth is
about the size of that of the Bengal tiger, and is therefore too large to have
belonged either to the panther or the jaguar. It is as much too small to
have belonged to the extinct American lion, or Fe/is-atroz, as its breadth is
but little greater than the sectorial molar contained in the lower jaw from
which the latter was described. The form of the tooth is the same as in the
American panther and Bengal tiger. The breadth of the crown is slightly
less, and its thickness proportionately greater than in the corresponding teeth

of a skull of the latter with which the fossil was compared.

228

If the upper sectorial molar of Felis atrox had the same proportionate size
to the lower one as in the Bengal tiger and other feline animals, it measured
nearly an inch and three-fourths in breadth. That of the Loup Fork fossil
is a little over an inch and a quarter in breadth. From the difference in size
thus indicated between the sectorial molar of the Loup Fork fossil and that of
the previously described largest American cats, recent and extinct, we may
fairly regard the specimen as characteristic of another species, for which the
name heading this chapter has been proposed.

Comparative measurements of the upper sectorial molar are as follows—
those from Lelis atrox being estimated, and that from the jaguar being taken.
from Plate XIV of De Biainville’s Osteographie:

Upper sectorial molar. F. concolor.| F.onga. |F. augustus.| TF. tigris. F. atrox.
; ; Lines. Lines. Lines. Lines. Lines.
Breadth or crownl-o2. essere Tal 12 154 16 20
Thiekness in front.......-.--- Dian. ames are 8 14 10°

Another specimen, represented in Fig. 18, Plate VII, consisting of a frag-
ment of a premaxillary retaining the second incisor, the first alveolus, and part
of the last one, agrees in size and other characters with the corresponding
part in the Bengal tiger.

The remaining specimens are fragments of an upper last premolar and of a
canine from the same individual.

A specimen, represented in Fig. 24, Plate XX, feund by Professor Hayden
on the Niobrara River, but not in proximity with the preceding, consists of
the distal extremity of a humerus, probably of the same animal. It has
about the same size, proportions, and form as in the corresponding part of
the arm-bone of the Bengal tiger. Its diameter at the supracondyles is 33
inches; the breadth of the articular surface in front is 22 inches. The hole
for the brachial blood-vessels and accompanying nerve is quite evident, though
the bony bridge defining it is broken.

FELIS IMPERIALIS.

Among a collection of fossils belonging to the cabinet of Wabash College,
Crawfordsville, Indiana, purchased from Dr. Lorenzo Y. Yates, of Centreville,
Alameda County, California, there are several which were kindly leaned to

229

me for investigation. The specimens consist of jaw-fragments of a large
wolf and tiger.

Professor E. O. Hovey writes me that they are part of a collection of fossil-
bones which were obtained from a wash in the side of a hill about twenty-
five miles inland from San Leandro, California. )

The fossils are not petrified, and indeed have undergone almost no altera-
tion, and are probably quaternary.

The fossil pertaining to a tiger consists of an upper-jaw fragment, repre-
sented in Fig. 3, Plate XXXI, one half size. It. contains the second pre-
molar, and retains the alveolus of the one in advance and that of the canine.

The specimen indicates a species as large as the largest living Bengal tiger,
and, indeed, is slightly larger than the corresponding part of the largest spec-
imen of a skull among many in the Academy Museum of Philadelphia.

The proportions of the specimen indicate a larger animal than the extinct
Felis augustus, as represented by the fossil-fragments from the Niobrara
River of Nebraska. ‘They also indicate an animal as much smaller than the
_ extinct £ atrox, as represented by the ramus of a lower jaw found in associ-
ation with remains of the Mastodon americanus and Megalonyx Jeffersoni,
near Natchez, Mississippi, as the Bengal tiger is compared with the latter.

Taking into consideration the extent of variation in size of the same
species, there can be no question that the California fossil might pertain to
either the Felis augustus or the F. atrox. Its associations might aid in the
- determination whether it was either of these, or whether it is distinct. If
found in association with remains of A/astodon americanus, it might reason-
ably be supposed to pertain to a smaller individual of Felis atrox; if with
any of the peculiar species of the Niobrara fauna, it might be supposed to be
a larger individual of F. augustus.

Comparative measurements of the fossil with the corresponding portion of

the skull of a large Bengal tiger from Hindostan,are as follows:

Fossil. Bengal

tiger.
P . Lines. Lines.

Space occupied by the upper premolars and canine. ...-....---- 3d4. 0 3a. 0
From back of last premolar to canine alveolus ..-...:.....-...- 21.8 19.0
Antero-posterior diameter of second premolar..........---.....- 12.2 12.0
Pe MeLer Ole Caan CralWeOMISre cao. 4 5 sac cciee sce once Sees ues ewes 14.0 13.5

230

CANIS.
CANIS INDIANENSIS.

The fossil specimen pertaining to a wolf consists of the right ramus of a
lower jaw, represented in Fig. 2, Plate XX XI. The specimen indicates an
animal larger than any individuals of the recent wolves of North America
and Europe, as represented by skulls I have had the opportunity of examin-
ing in our Museum of the Academy. It, however, indicates a less robust
animal than that formerly described by me under the name of Canis primevus,
and subsequently as C. imdianensis, from an upper-jaw fragment, found in
association with remains of Megalonyx, &c., on the banks of the Ohio River,
Indiana.

The specimen likewise indicates a less robust species than the C. Haydeni,
of the Pliocene formation of the Niobrara River, but a larger one than C.
s@vus, of the same formation.

I am disposed to view the specimen as pertaining to the C. indianensis,
and perhaps it was not different from the existing C. occidentalis.

Measurements of the fossil, in comparison with those of the skull of a large
wolf from the Columbia River, Oregon, and of another from Germany, are as

follows :

Fossil Oregon | European

jaw. ~ wolf. wolf.

Lines Lines. Lines.
Length of jaw from condyle to fore part of canine ..... 96. 0 $0.0 | 86.0
Depth of jaw aticondyle 2 hee tae ses eee 21.2 20.5 20.5
Depth of jaw at coronoid process..-.....-...-..-..... 40. 0 36, 4 37.5
Depth of jaw at sectorial molar ...................--- 18.0 0G) 15.0
Depth of jaw at second premolar..2.-550---2-.--25-=- 16. 6 14. 0 12.5
Length of molar series with canine .......--...--..--. 66. 0 61.0 59. 4
OEE OF WOE SSH SS 5. c2b5 sosG205s000ca9052 505-05 o4. 0 50. 0 45. 0
Antero-posterior diameter sectorial molar .......--.--. 16.4 14.6 14.3
Antero-posterior diameter caniné.-.......-.---.----- : 8.4 6.8 6. 2

LUTRA ?

A specimen of a tibia, submitted to my inspection by the Smithsonian
Institution, is represented in Fig. 4, Plate XX XI. It was presented by
Clarence King, and was obtained by him on Sinker Creek, Idaho, in associ-
ation with remains of Hquus excelsus and Mastodon mivificus.

231

The tibia pertains to a carnivore, and resembles that of an otter more than
that of any other animal with which I have an opportunity of comparing it.
Its differences, excepting size, are trifling. The tubercle for insertion of the
quadriceps extensor is less prominent, soas to give the head of the bone pro-
portionately less thickness in relation with its breadth. The ridge for the
attachment of the interosseous membrane at the lower part of the bone is
more prominent and sharper. The distal end in front just above the articu-
lation is flatter, and the groove for the flexor tendons behind is deeper.

° Lines
Length of the bone internally.....--... ep SRI Bec eene te I Sane eer a 59
“MEGED DP UG LGC! te koe eels eal te eS ea ees eg 15
iinnekness atthe imer-condyle. .. 2... -.-.- 2222-622 see ene Woy ess tags fac 104
Width of the distal end between the most prominent points -......-......---.- 11
Mucknessvat the inner malleole .-....-.-.-...--2------+-- bee Pierre acs tapes ome ei 8

Order Proboscidea.
MASTODON.

MastTopon OBSCURUS.

Besides the well-known American mastodon, WM. americanus, of the post-
Tertiary period, there appear to have been at least three others which in-
habited this continent. Characteristic remains of a species, to which the
name of M. mirificus was given, were discovered by Professor Hayden, in
association with an abundance of remains of many other extinct animals in
the Pliocene formation of the Loup Fork of Platte River, Nebraska. Re-
mains also, apparently of the same species as the South American MZ. andium,
have been found in Central America. For an account of the remains of the
two species last named, the reader is referred to the ‘“ Extinct Mammalian
Fauna of Dakota and Nebraska.”

In the Museum of the Academy of Natural Sciences of Philadelphia,
there is a cast in plaster of a mastodon tooth, the original of which is reputed
to have been found in the Miocene formation of Maryland. The original
specimen having been lost, the cast is represented in Fig. 13, Plate XX VII,
of the work just named. ‘This, together with the fragment of a similar
tooth, represented in Fig. 16, of the same plate, has been taken in evidence
of the existence of a fourth species, to which the name of JZ. obscurus has
been given.

Dr. Lorenzo G. Yates, of Centreville, Alameda County, California, has

communicated to the writer a list of localities in which he has discovered re-

232

mains of mastodons in that State. Specimens collected by him were sent to
Professor C. U. Shepard, of Amherst, Massachusetts, who has submitted
them to the examination of the author.

One of the specimens, a last inferior molar tooth, represented in Figs. 1, 2,
Plate XXI, was found together with the mutilated lower jaw and upper molars,
at Oak Springs, in Contra Costa County. The, remains were obtained from
the rock at the base of one of the rounded hills, of Tertiary age, mentioned
~in Professor Whitney’s Geological Survey of California, p. 32, stretching
along near the edge of the San Joaquin plain. According to Mr. William M.
Gabb, the formation belongs to the Plocene Tertiary period.

A small photograph, sent to me by Dr. Yates, exhibits the lower jaw with-
out the ascending portions behind, and with straight tusks projecting with an
upward direction. The tusks appear to be as long as the jaw was in its com-
plete condition.

The molar tooth has the same general form and constitution as the corre-
sponding one of the American mastodon, but is smaller than is usual in this
species. It resembles the plaster-cast above mentioned sufficiently to render
it probable that it belonged to the same animal.

he crown of the tooth is composed of four transverse pyramidal ridges,
each consisting of a pair of lobes, and conjoined in a common, broad, low
base, without a conspicuous offset or heel. As" in the cast of the Maryland
tooth, the inner lobes are ‘more mammillary or less angular than in JZ. ameri-
canus. In this respect they approach the condition, even more marked, how-
ever, in the M. angustidens of Europe, and they are well separated to their
base as in MM. americanus. The outer lobes of the crown have the same form
as in the latter, but are provided with distinct offsets projecting from their
inner part fore and aft. The contiguous offsets come into contact, and thus
obstruct the transverse valleys of the crown. This arrangement accords
with that of the cast of the Maryland tooth. In AZ, americanus similar offsets
from the outer lobes are usually but feebly developed, and scarcely obstruct
the bottoms of the transverse valleys.

The enamel wern from the summits of the anterior of the inner lobes
leaves a transverse ellipsoidal cup of exposed dentine, as usual in the same
position in the American mastodon. A greater degree of wearing on the
corresponding outer lobes has produced quadrilobate excavations of dentine,
in which the specimen agrees with the plaster-cast. In the same stage of

wear in AZ. americanus, the excavations have a more lozenge-like outline.

233

The anterior three divisions of the crown are nearly alike in size and con-
struction. The fourth division is less well developed, and consists of a pair
of conical lobes, but:*the inner is much smaller than the other, and is connate,
with a supplemental lobe in advance. Back of these there is a small conical
tubercle, corresponding with the heel or rudimental fifth division of the crown
in M. americanus.

In the plaster-cast of the Maryland tooth, the fourth division of the crown
consists of a pair of nearly equal conical lobes, embracing a smaller pair
at their fore part. Behind these there is a pair of conical tubercles corre-
sponding with the single one in the California tooth. The differences inde
cated between the posterior extremity of the crown of the latter and the
cast of the Maryland tooth are not greater than those observed between the
same teeth of different individuals of MZ. americanus, and are therefore unim-
portant as distinctive characters. eat

Well-developed elements of a basal ridge, in the California tooth, occupy
the outer fore part of the crown and the intervals of the outer lobes. Between
the posterior three divisions of the crown they are better marked than in the
cast of the Maryland tooth, or even than is usually the condition in the
American mastodon. The ridge is also distinctly produced around the outer
part of the third and fourth external lobes and the back of the crown, which
is not the case in the cast, nor usually in AZ. americanus.

The jaw-fragment containing the tooth is too much mutilated to ascertain
anything of importance in regard to it, other than that it measured about 65
inches in depth at the fore part.

Comparative measurements of the California tooth, the cast of the Mary-

land tooth, and two teeth of AZ americanis are as follows:

| MM. americanus.
Last lower molar. California. Maryland. ——
Female. | Male.*
: pe ae . |
| |
| Lines. al Lines. Lines. | Lines.
Fore and aft diameter of crown ........- ttre | 75 75 (5) | 90°
Breadth at anterior three ridges ..........---- 33 B33 38-42 | 41-45
Breadth at fourth ridge ......-.... See ene ae Op 28 aa | 39
Height of third inner lobe, unworn.....---.--. | 2% | 26 28 | 34
* , | : - | ;
Heisht of fourth inner lobe.......-....--.-.--- 16 20°75 208 | 30
Hechinor tourth outer lobe...........-..-..--- | 24 22 22 | 30
| | | |

* The specimen of the tooth of a male has five transverse divisions to the crown in addition to a small

heel.
30 G

204

The second specimen received from Professor Shepard consists of the
fragment of a tusk, from Dry Creek, Stanislaus County, California. It was
discovered by Dr. Yates imbedded in the bluff of a hill, about ten feet above
the bed of the creek. The hill, upward of a hundred feet in height, is one
of those mentioned in Professor Whitney’s Geological Survey as being
scattered over the San Joaquin plain, at the base of the foot-hills of the
Sierra Nevada.

The specimen is represented in Figs. 3, 4, Plate XXI, and is, remarkable
from its exhibiting characters which indicate the species to have been nearly
related with the Mastodon augustidens of Europe. The molar tooth from
Contra Costa County, likewise presents a form which approximates it to the
same animal, so that it is probable both specimens may belong to the same
species.

The fragment is six inches long, slightly curved in two directions, and in
transverse section (Fig. 3) is ovate, with the anterior pole acute. The pulp-
cavity, opening half the diameter of the tusk atits larger broken end, extends
half the length of the specimen. On one side of the tusk, as in Mastodon
augustidens, there is a broad layer of enamel, which extends from the acute
border two-thirds the width of the specimen. The enamel is somewhat
rugose, and is two-thirds of a line thick. In one position, near the smaller end
of the fragment, it has been worn through irregularly for the extent of about 14
inches. ‘The convex or thicker border of the tusk has also been worn off to
an extent of two-fifths of the surface. , The broken ends of the fragment exhibit
the usual decussating lines of structure of the dentine so characteristic of
the ivory of the great proboscidians.

The entire length of the tusk appears to have approximated two feet. The
other dimensions are as follows:

Lines.
Long: diameter of the larger extremity .----.---..--.----- 2-2 «= s)--5 = eee 28
Short diameter of the larger extremity.......-----.-.-.--.- sfio0se > 49
Long diameter of the smaller extremity ..--..-< --.----<-2-- == 2s 255 2
Short diameter of the smaller*extremity. ..--- Evon Seine =2.o a2 genet 16
Breadth of enamel layer at larger extremity --:: --...2--.-.--2--ce= 2-2 22
Breadth of enamel layer at smaller extremity ....---.----------...25-2 ===

In the form of the tusk and the possession of an enamel band it resembles
tle same organ in the Mastodon augustidens. The specimen when first de-
scribed was viewed as probably representing a species distinct from that to
which the Contra Costa specimens pertained, and was therefore referred to an

235
animal with the name of Mastodon Shepard, in honor of Professor C. U.
Shepard.

Since writing the above, I have received another specimen from Professor
Shepard, consisting of a last inferior molar tooth, obtained ‘by Dr. Yates in
Contra Costa County, California. It is almost identical in form and size with
the one previously described from the same locality, but appears to have be-
longed to an older individual, as indicated by the more worn condition.

From the: Smithsonian Institution I have recently received for examination
some remains of a mastodon and an elephant, which were found near Santa
Fé, New Mexico, and were presented to the institution by the Hon. W. F.
M. Arny. The mastodon remains consist of three fragments of a lower jaw,
a vertebral body, anda rib-fragment. They are white, and from adherent por-
tions of matrix appear to have been imbedded in an indurated clay. The
eancellated structure of the bones is filled with the same matter together
with crystalline calcite.

The lower-jaw fragments appear all to have pertained to the same specimen.
One of them, represented in Fig. 1, Plate XXII, consists of a portion of the
right ramus containing the last molar tooth nearly of the size of the corre-
- sponding part in the American mastodon. The molar tooth, represented in
Fig. 4 of the same plate, has lost the portion back of the third ridge of the
crown. ‘The portion preserved sufficiently resembles in its construction the
_ corresponding portion of the California tooth above described to belong to
the same species, which I suspect actually to be the case. It also resembles
more nearly the corresponding: portion of the same tooth of JZ. augustidens
of Kurope than it does that of the JZ. americanus.

The other jaw-fragments, represented in Figs. 2, 8, form together the
anterior extremity of an enormously prolonged symphysis, like that of JZ.
augustidens. ‘The specimen is rather more than a foot in length, and contains
portions of tusks extending through the pieces and broken off on a level with
the extremities of the symphysis. This has been somewhat crushed laterally,
so as to disarrange the proper relative position of the two tusks. It is of
nearly uniform width, but widens at the posterior extremity. Below, it is
slightly convex or nearly straight longitudinally, and is depressed along the
median line. The sides are convex, and extend upward in ridges which form
the boundaries of a deep groove at the upper part of the symphysis. The
groove is narrower behind, and becomes shallow in front. The tusks are

236

slightly compressed cylindrical, and curved in their course. They are oval in

transverse section, with the long diameter directed from within upward and
outward. ‘They are unprovided with enamel, and at the broken ends exhibit
the decussating curved lines of structure of the ivory enveloped in a thick
layer of dense cementum. At the posterior extremity the broken ends ex-
hibit the pulp-cavity occupied with matrix and surrounded with a margin of
about a line in thickness, so that the symphysis is broken off near the bottom
of the incisive alveoli.

From the thinning of the anterior alveolar borders of the symphysis it
would appear as if the latter was nearly complete, so that if we suppose the
lower tusks projected about 6 inches from the jaw, it would give them an
entire length of about 20 inches.

The breadth of the fore part of the symphysis, in its complete condition,
is rather more than 5 inches. At the back part, corresponding with the posi-
tion of the bottom of the incisive alveoli, it has been about an inch wider.

The long diameter of the tusks, at their anterior broken ends, is about 20
lines; the short diameter 17 lines. These diameters are nearly uniform
throughout as existing in the specimen. .

The fore and aft diameter of the last molar tooth, when complete, is esti-
mated to have been full 6§ inches. The width of the crown at the base of

the second and third ridges is 35 lines. The measurements indicate the pro-

portions of the tooth to be slightly greater than in the corresponding Califor-
nia tooth or the cast of the Maryland tooth.

The depth of the lower jaw below the second ridge of the last molar is 64
inches; and the thickness is 5 inches.

I think it probable, without being positive in the matter, that the Masto-
don remains above described, which have been referred to species under the
names of Mastodon obscurus and M. Shepardi, including those from New Mex-
ico, belong to one and the same species. ‘This, from the ferm of the molar
teeth, the constitution of the upper tusks, and the prolonged symphysis of
the lower jaw, was clearly a near relation of the Mastodon augustidens of
-Hurope.

In a note, on page 74, of volume II, of the Palaeontological Memoirs of the
late Dr. Falconer, it is stated that at Genoa he had seen a cast of a lower jaw
of a mastodon from Mexico, with an enormous bec abruptly deflected down-

ward, and containing one very large incisor. The beak is much thicker than in

ee

237

M. augustidens and larger than in M. longivostris. “The outline of the jaw re-
sembles very much the figure in D’Orbigny’s voyage, described by Laurillard
as M. andium. The Genoese paleontologists had named it Rhynchotherium,
from the enormous development of the beak, approaching Dinotherium.”
Perhaps this Mexican specimen of a lower jaw may pertain to the same
species as the specimens above described, though the beak of the New Mex-
ican specimen is unlike that of the figure above alluded to in the work of
D’Orbigny. : .
The vertebral body and rib-fragment accompanying the jaw-fragments from
New Mexico present nothing remarkable. ‘The former is of a lumbar verte-
bra, and would indicate an animal about as large as the living Asiatic elephant.
Its length is 34 lines; its breadth is about 5 inches at the posterior border ;

and its height is 34 inches.

MASTODON MIRIFICUS.

- Some small fragments of jaws and teeth, apparently referable to this species,
in the museum of the Smithsonian Institution, were obtained by Mr. Clarence

King, from Sinker Creek, Idaho.
MASTODON AMERICANUS.

Among a collection of remains of the American mastodon, from Benton
County, Missouri, deposited in the museum of the Academy of Natural Sciences
of Philadelphia by the American Philosophical Society, there is a singular
tooth, which I suppose to be of abnormal character and to pertain to the
Mastodon americanus. The specimen is in the same state of preservation as
the associated remains, and is represented in Figs. 5 and 6, Plate XXII. It
consists of the complete crown of a molar tooth without the fangs. Its-shape
is so peculiar that I can form no clear idea as to the relative position it occu-
pied in the jaws, or as to its homologous character in comparison with normal
teeth.

The crown in transverse outline is irregularly oblong oval, more bulging
on one side than the other, and somewhat prolonged at the extremities. Irom
a thick expanded base there project four conical lobes, of which the interme-
diate two are nearly equal and nearly twice the size of the others, also nearly
equal in size. The basal ridge on the more prominent side of the crown is
mammillated, and twice the depth that it is upon the other side, in which

position it is comparatively smooth.

238

The long diameter of the crown is 55 lines; the short diameter, 29 lines.

A small collection of fossil teeth, from near Pittstown, on the Susquehanna
River, in Luzerne County, Pennsylvania, now preserved in the Museum of the
Academy of Natural Sciences, is of interest on account of the association.
‘The specimens consist of two molars of Mquus major, hereafter described, a
molar of Bison latifrons, also to be described, and three first premolars, ap-
parently from as many different individuals of Mastodon americanus. Of these
one is represented, of the natural size, in Fig. 9, Plate XXVIII.

ELEPHAS.
ELEPHAS AMERICANUS.

In the preéeding account of the remains of mastodon from near Santa
Fé, New Mexico, those of an elephant are referred to which were found
in association with them. There is but one specimen, consisting of the back
part of a molar tooth, apparently the last upper one. It is composed of eight
unworn lobes, decreasing successively in length. They present the ordinary
thin, elongated, palmate appearance, with the digitate extremities curving for-
ward and ending in mammillary points. The eight plates occupy a space
of 43 inches. The second of the plates is 32 inches broad near the middle,
and when entire was upward of 7 inches in length. .

The specimen is insufficient to determine whether it pertained toa species
different from the ordinary Elephas americanus, and it presents nothing pecu-
liar. The thickness of the lobes, or double plates, indicates the coarse-plated
variety of teeth of the American elephant, named by Dr. Falconer Elephas
columbi.

Since the above was written I have received, from the Smithsonian Insti-
tution, for examination some remains of an elephant from Chihuahua. Pro-
fessor Baird reports that the remains came from an ancient lagoon-bed at
Potos Spring, seventy-five miles south of El Paso, Texas, and were presented
to the institution by General Carleton, United States Army.

The specimens consist of fragments of molar teeth with adherent gravel,
and with the exterior cementum much worn away by water action. They
indicate the coarse-plated variety of teeth of the American elephant. One
of the better preserved specimens consists of the fore part of a last lower
molar about one-third worn down. It comprises about eight lobes, or double
plates, included in a space of 58 inches. The width of the sixth lobe is 3%

239

inches. The first lobe is nearly obliterated, and its back plate conjoins the
contiguous one of the second lobe.

Another specimen consists of the back part of a molar with six lobes,
occupying a space of nearly 4$ inches. ‘The lobes exhibit the same narrow,
elongated, palmated form, with curved digitate extremities, as m the molar
fragment from New Mexico. The first of the six lobes is worn off at. the
summits of the digitate ends. The others are unworn, and the second plate

is 383 inches wide near its middle.

MEGACEROPS.

MEGACEROPS COLORADENSIS.

An imperfectly known extinct animal, which was supposed to be related
with the great ruminant, the Sivatherium of the Tertiary formation of the
Sewalik Hills of India, is indicated by a singular looking fossil discovered in
Colorado. The specimen belonged to Dr. Gehrung, of Colorado City, by
whom it was presented to Professor Hayden. It is represented one-half the
natural size in Figs. 2, 3, Plate I, and Fig. 2, Plate II, and was originally
described in the Proceedings of the Academy of Natural Sciences of Phila-
delphia for January, 1870, under the name heading this article.

The fossil is singularly puzzling in its character, and possesses so little in
common with the homologous portion in ordinary animals that its relation-
ship would have remained unknown, or entirely conjectural, had we not been
previously acquainted with the Sivathertum. The specimen appears to cor-
respond with that portion of the face of the latter which comprises the upper
part of the nose, together with the forehead and the anterior horn-cores. As
is described to be the condition in the corresponding portion of the skull of
Sivatherium, all the bones entering into the constitution of the fossil are
completely co-ossified, so as to leave no traces of the original course of the
sutures. The nasal and contiguous bones are of great thickness, and as solid
as those generally in the living Sirenians.

The horn-cores of the Colorado fossil resemble the anterior ones of Siva-
therium both in form and relative position. They are large, dense, conical
knobs, somewhat trilateral, and with a rounded, dome-like summit, which is
more porous on the surface than any other part of the fossil. They are
nearly straight, and divergent ftom each other, and their summits project
more over their base externally than in Sivatherium.

240

’

The space between the horn-cores extending across the forehead forms a
deep concavity divergent outwardly, The surface of the forehead from the
broken border of the specimen behind to the end of the nasals forms a mod-
erate uninterrupted convexity. In Sivatherium, the rhinoceros, and the tapir,
the corresponding surface is interrupted by a concavity at the root of the nose.

The face, as formed by the nasals and their apparent conjunction with the
maxillaries in advance of the position of the horn-cores, is exceedingly short
in comparison with the corresponding part in Sivatherium and the rhinoceros,
and is more like that in the tapir.

The nasals together form a strong, thick, tongue-like process, projecting
free from their conjunction with the frontals in advance of the horn-cores.
The overhanging process of the nose is proportionately wider, thicker, and
longer than that of Sivatherium. Its upper surface is not vaulted as in the
latter and the rhinoceros, but simply continues the convexity of the forehead.
The lateral margins are somewhat expanded, (not sufficiently expressed in
Fig. 2, Plate I,) and are thinner than elsewhere. The end is thicker than at
the sides, is more obtuse than in Sivatherium or the tapir, and is roughened
and porous, probably to have given firmer attachment to a proboscis. _ A
notch occupies the extremity of the obliterated internasal suture.

One of the most remarkable characters of the Colorado fossil is the great
comparative extent of the lateral nasal notch. It not only exceeds that of —
Sivatherium, but also that of the rhinoceros and tapir. In the former its
bottom is far in advance of the position of the horn-cores, and in the rhi-
noceros it holds nearly the same relative position. In the tapir the notch
extends back over the position of the orbits. In the Colorado fossil it
extends far back beneath the position of the horn-cores, where the nasals
apparently conjoin the maxillaries. The relative position of the orbits cannot
be ascertained in our fossil, as all the contiguous parts are brokeh away.
They appear as if they had been situated farther posteriorly in relation with
the position of the horn-cores than in Sivatherium. The horn-cores, project-
ing forward and outward, overhang a large recess, which would appear to
have been just in advance of the orbit, and is situated externally above and
behind the lateral nasal notch.

The broad and stout projecting nasals were probably intended as a point’
of attachment for a movable snout or proboscis, intermediate in degree of
development to that of the tapir and elephant or mastodon. The similar

241

constitution of the nose of Sivatherium led ie discoverer and deseriber, Dr.
Falconer, to attribute a like prehensile organ to that animal. ‘The strength
and co-ossification of the nasals, together and with the frontals and maxilla-
ries, are also no doubt related with the unusual position of the horn-cores, just
as a similar condition of things in the rhinoceros is related with the support
of a horn on the nose.

Megacerops coloradensis is estimated to have approximated two-thirds the
size of the Swathertum giganteum.

Measurements from the fossil referred to Megacerops coloradensis are as

follows :
Inches. Lines.
Distance from the summit of one horn-core to the other................ eae) 6
Length of curve between the same two points ...-......--.--..--..+-+--. a TO
Length of lateral nasal notch from end of nasals.........--- eee Eee atk 6
Distance from end of nasals to center of space between horn-cores ... ... 6 0
Breadth of nasals 24 inches behind the end .....- AN eae wave ge nia Hk 4 3
munickmeds: Of Masals where Co-ossified .-- ~:.2... --<+ 2-22 ss. e eee en eeee 1 3
Diameter of horn-cores 24 inches from comnts fore IMO: 2. he pare Ae 2 1G
Diameter of horn-cores 24 inches from summit transversely .........-...- 2 5
emediiinot face below horp-cores.......-.-.+-.-.--.-s00--2. 00-00 - ue ese 8 8
Breadth at bottom of lateral nasal notches.....-...........-..-..-- ae 6

Since writing the above, I have recalled to mind a specimen of a horn-core
which was obtained by Dr. John Evans from the Mauvaises Terres of White
River, Dakota, and which is noticed in the account of Titanotherium, on page
216 of the “ Extinct Mammalian Fauna of Dakota and Nebraska.” The ref-
erence of the specimen to any particular animal was considered very uncer-
tain, though it was suspected that it might pertain to Titanotherium. It is
now represented in Fig. 3, Plate XXVIII, and is seen by comparison to bear
a near resemblance to the horn-cores of Megacerops. It is rather larger and
slightly more tapering and curved than in the latter: The specimen may,
perhaps, belong to another species of Megacerops.

Since the foregoing was written, Professors Marsh and Cope have reported
the discovery of remains of several huge mammals in the Bridger Tertiary
beds, which they have described under the names of Tinoceras, Dinoceras,
Kobasileus and Loxolophodon. The ordinal relations of these is a matter of
dispute, and it is a question especially whether they are proboscideans, or are
representatives of a previously unknown order. One of their most remarkable
peculiarities is the possession of several pairs of bony protuberances to the
skull, which are viewed as horn-cores.

31 6

242

Ina recent paper entitled “On the Gigantic Fossil Mammals of the Order
Dinocerata,” by Professor Marsh, published in the American Journal of Sei-
ence for February, 1873, there is a representation of an almost complete skull,
described under the name of Dinoceras mirabilis. his skull, which appears
to agree with the corresponding parts, including the teeth, described in the
preceding pages under the name of Uintatherium robustum, is represented
with three pairs of bony protuberances, or horn-cores. In comparing the
Colorado fossil, it would appear that the horn-cores accord with the second
pair of the Wyoming fossil, in which they are seen to spring from the upper
part of the maxillaries, where these join the nasals.

The resemblance between the specimen belonging to Megacerops and the
skull described by Professor Marsh renders it probable that the former
belongs to the same order, instead of to the ruminants, as previously sup-
posed.

Order Soldungula.

EQUUS.
EQUUS OCCIDENTALIS.

The remains of equine animals which of late years have been discovered
both in North and South America indicate a number of species and genera
really wonderful, when we take into consideration that neither continent pos-
sesses a single living indigenous species. The remains from many parts of
North America, mainly consisting of isolated molar teeth, which have come
under my observation, exhibit so much difference in size and variation of the
enamel-folding, as displayed on the worn triturating surface, that im many
cases I have failed to refer them to species with any degree of certainty-

In the Proceedings of the Academy of Natural Sciences of Philadelphia
for 1865, page 94, I have given a notice of two specimens of upper molars
from California, submitted to my examination by Professor J. D. Whitney,
which were referred to a species with the name of Equus occidentalis. One
of these specimens is represented in Fig. 2, Plate XX XIII, and was obtained
from auriferous clay, at a depth of thirty feet from the surface, in Tuolumne
County, California.

Subsequently, in the same Proceedings for 1868, page 26, and in the
“Extinct Mammalian Fauna of Dakota,’ &e., I described a number of re-

mains obtained by Professor Hayden on Pawnee Loup Fork of the Platte

243

River, and on the Niobrara River, Nebraska, which I referred to a species
with the name of L. exce/sus. A characteristic specimen referred to the latter
consists of a portion of the upper jaw containing the back four molars, repre-
sented in Fig. 31, Plate XXI, of the work last named. The teeth in this
specimen are so nearly identical in character with those from California,
referred to E. occidentalis, as may be seen by comparing the figure with
Figs. 1, 2, Plate XX XIII, of the present work, that there can be little doubt
of the two named species being the same.

Since the original description of the two specimens referred to L. occiden-
talis, 1 have seen others of half a dozen different individuals from California.
All these present: sufficient correspondence in peculiarity of character as to
render them fairly representative of an extinct species, for which the name
of E. occidentalis is appropriate. Fig. 1, Plate XX XIII, represents a series
of the anterior four upper molars contained in a jaw-fragment. The speci-
men, together with another similar one from a second individual, and contain-
ing all the molars except the last one, were obtained by Dr. George H. Horn
from an asphaltum deposit near Buena Vista Lake, California, and presented
to the Academy. Similar specimens have also been submitted to my exam-
ination, obtained at the same locality by Professor Whitney.

The upper molar teeth of E. occidentalis are about the size of those of the
larger varieties of the domestic horse. From them they are in general
readily recognizable by the greater simplicity in the course of the enamel
lines, as displayed on the worn triturating surface, and in the absence of the
small enamel-fold, directed inwardly, at the bottom of the oblique valley
between the inner principal folds of the crown, in which point these teeth
accord with those of the existing ass.

The measurements of the specimens referred to /. occidentalis and repre-

sented in the figures are as follows :

Specimen of Fig. 1. aye Transverse
5 posterior. :
Lines. Lines.
EAMG HeMOMESb MOM. «562.65 oe i 52002 Sais ok Se see e ee wee ee es 18 13
REE IrerOmOn CECONG MOlan oo. ese kee See eee ese enw need 143 143
LOTS OL DRG LINO) ENR tt sO ae eee ee 144 143
HOLImMeLen Oe tourhh mOlay in... 2 ka Lk ee ee ened 124 134

244

Specimen of ig. 2, representing a second or third molar :

Lines.
Length externally ...... Sharla aia Ear ee Reh aN eat ok ene EER ee! os 27
Antero-posterior diameter of triturating surface..........--.....-...-..---..-- 154
TransversetdtamMeser: {2 = Ale Ss ke es Sete oe ee ee ee ee ea 134

A tooth in the collection of the Smithsonian Institution, apparently refer-
able to the same species, was discovered by Mr. Clarence King on Sinker

Creek, Idaho.

EQUUS MAJOR.

Figs. 3 to 17, Plate XX XIII, represent specimens, from different localities
of the United States, which are viewed as pertaining to an extinct horse,
originally referred by the author to a species under the name of Equus com-
plicatus, and which is suspected to be the s@me as that which was first desig-
nated by Dr. Dekay under the name of Lquus major.

Figs. 3, 4, 7 to 10, 12, 13, represent specimens of teeth submitted to my |
examination by Messrs. D. G. Elliot and George N. Lawrence, of New York.
They were obtained from an asphaltum-deposit and from a stratum of clay
beneath, in Hardin County, Texas, and were found in association with remains

of mastodon and other extinct animals.

Figs. 3, 4 represent a first upper molar of the right side. It differs in no
important degree from the corresponding tooth of the domestic horse, but is
somewhat larger than usual, and is less simple in the course of the enamel
lines on its triturating surface.

Figs 5, 6 represent a similar tooth, from Tlinois Bluffs, Missouri, six miles
west of Saint Louis. According to the late Dr. B. F. Shumard, it was derived
from the quaternary formation of Missouri.

Figs. 7, 8 represent a last superior molar of the right side, accompanying
the first molar, from Hardin County, Texas. It is remarkable for its great
extent of curvature compared with the corresponding tooth in the recent
horse, The arrangement of the enamel is similar to that in the latter, and is
but little more complex than usual.

Fig. 9 represents a last lower molar, and Fig. 10 a fifth lower molar. These
present nothing peculiar distinguishing them from the corresponding teeth of
the recent horse.

Fig. 11 represents a second or third upper molar of the right side: The
specimen was found by Dr. Thomas H. Streets, in a gully of Galveston Bay,

245

Texas, and presented by him to the Academy of Philadelphia. In the com-
plexity of folding of the enamel, as seen on the triturating surface, this tooth
is quite characteristic of Hquus complicatus.

Fig. 12 represents a first lower temporary molar, one of the specimens from
the asphaltum-bed of Hardin County, Texas. F

Fig. 13 represents an upper last temporary molar, another of the specimens
from the locality just indicated.

Fig. 14 represents an upper molar of Hquus complicatus from the “ phos-
phate-beds” of Ashley River, South Carolina.

Fig. 15 represents an inferior molar from the same locality. The upper
molar, in the complex condition of its enamel-folding, is characteristic of the
species. ‘The lower molar presents nothing distinctive from those of the
recent horse.

Teeth of horses are frequently found in the Ashley phosphate-beds, mingled
with abundance of fossil shark-teeth, remains of mastodon, elephant, &c.
Many of them are undistinguishable from those of the recent horse, but others

in size and complexity of the enamel-folding in the superior molars are sufh-
Ss I

‘ciently characteristic of Equus complicatus.

Figs. 16 and 17 represent an upper and a lower molar, which were found
associated with remains of mastodon at Pittstown, on the banks of the Sus-
quehanna River, Luzerne County, Pennsylvania. The teeth are more than
half worn away. ‘Their size, and a rather greater degree of complexity than
usual in the enamel lines of the triturating surface of the upper molar, would

probably indicate that they belong to Equus complicatus.

Measurements of the specimens, represented in Figs. 3 to 17, and referred

to EL. complicatus, are as follows:

First upper molar, Figs. 3, 4.—Length of crown externally, 35 lines; antero-posterior
diameter, 21 lines; transverse diameter, 15 lines.

First upper molar, Figs. 5, 6.—Length of crown, 33 lines; antero-posterior diameter,
21 lines; transverse diameter, 154 lines.

Last upper molar, Figs. 7, 8.—Length at antero-external border from end of fang, 36
lines; length posteriorly, 19 lines; breadth of triturating surface, 19 lines; width, 2
lines.

Last lower molar, Fig. 9.—Breadth, 164 lines; width, 7 lines.

Fourth or fifth lower molar, Fig. 10.—Length of crown, 34 lines; cage a 135 lines;
width, 7? lines.

ce second or third molar, Fig. 11.—Length of crown, 32 lines; breadth, 14 lines;
width, 15 lines. P Q

First lower temporary molar, Fig. 12:—Breadth, 174 lines; width, 8 lines.

_

246

Last upper temporary molar, ig. 15.—Breadth, 17 lines; width, 10 lines.

Upper second or third molar, Pig. 14.—Length of crown, 25 lines; breadth, 14 lines;
width, 15 lines.

An intermediate lower molar, Irig.15.—Length of crown, 24 lines ; breadth, 134 lines;
width, 93 lines.

Upper molar, Fig. 16.—Length of crown, 22 lines; breadth, 133 lines; width, 143 lines.

Lower molar, Fig. 17.—Length of crown 224 lines; breadth, 14% lines; width, 113
lines.

Among a small collection of fossils from Texas, submitted to my examina-
tion by Professor 8. B. Buckley, there is a specimen of an upper molar tooth
of a horse of peculiar character, represented in Fig. 18, Plate XX XIII.
The exact locality from whence the specimen was obtained is unknown.
The tooth is apparently a fourth or fifth of the series, and is only sufficiently
worn to exhibit the course of the enamel layers on the triturating surface.
The tooth is longer than in the domestic horse, and is rather narrower than
usual in relation with its fore and aft diameter. The folding of the enamel
defining the median lakes of the triturating surface is as complex as in Equus
complicatus, but in a different position. In the latter the folding is greatest
on the contiguous sides of the lakes, as seen in Figs. 11 and 14, but in the
tooth under consideration the contiguous sides of the lakes are less folded
than usual even in the domestic horse, while the enamel border at the inner
sides of the lakes is folded in an unusual degree.. Further, the broad inner
peninsular fold of the triturating surface, which in the domestic horse and
other known species has a simple oval, elliptical, or reniform outline, in this
specimen is of extreme width, narrow, and folded at the extremities. The
width of this inner fold or column is uniform throughout the length of the
crown.

The length of the crown of this tooth, without the fangs, in the entire con-
dition has been upward of 4 inches,. Its fore and aft diameter at the trit-
urating surface is 16 lines; its transyerse diameter at the middle of the same
is 1 inch.

Fig. 19, Plate XX XIII, represents a fragment of an upper molar sub-
mitted to my examination by Professor J. 5S. Newberry. It was obtained
from the lignite-beds of Shoalwater Bay, Washington Territory. It presents
nothing which distinguishes it from the corresponding part of the molars
of the domestic horse.

The length of the crown externally is 23 inches, and the fore and aft
diameter of the triturating surface is 14 lines.

247

HIPPARION.

A small collection of fossils, submitted to my examination by Professor 8.
B. Buckley, mainly consist of equine remains, of which the determination is
uncertain and the near relations obscure. Most of them were obtained in
Washington County, Texas, a few in the contiguous county of Bastrop, and
several others in Navarro County. They were usually found in digging wells,
at the depth of from 25 to 30 feet, imbedded in a rocky stratum. Most of
the specimens are free from matrix, but several have attached portions of a
hard arenaceous limestone. From the character of the fossils, I suppose the
formation to be of contemporaneous age with that which has been called Plio-
cene Tertiary of the Niobrara River, Nebraska, Little White River, Dakota,
and that noticed in the preceding pages of the Sweetwater River, Wyoming.

Fig. 14, Plate XX, represents a specimen labeled as having been obtained
. from an ossiferous rock at a depth of 25 feet, in Washington County, Texas.
It is a last upper molar of a small equine animal, and is moderately worn
away at the triturating surface. It is strongly curved, and is nearly twice the
length antero-externally that it is postero-internally. In the isolation of the
antero-internal column from the antero-median column, as seen on the triturat-
ing surface, it accords with the character of Hipparion. It sufficiently re-
sembles in its relative proportions, and the complexity of arrangement of its
enamel-folds, the fragment of a tooth, represented in Fig. 17, Plate XVIII,
of the Extinct Mammalian Fauna of Dakota, &c., to belong to the same species.
The latter specimen was also obtained in Washington County, Texas, and has
been referred to Hipparion speciosum, a species originally proposed from
specimens discovered at Bijou Hill, Dakota, and represented in Figs. 16, 18
and 19 of the work just indicated.

The measurements of the specimen are as follows:

Lines.
ene nnnOn crown anvero-extermally: .......-....--..-----+ 2-2. ete eee es Lee ee 113
Penaviegrerown postero-intermally ....-...-...-.-s-----+- +--+ sewn n eee eee 64
Breatutn of crown antero-posteriorly .-..--.-..--..---.-.---s.f2e ee ase aay Ee Ge
Pe MUMnGInCrOwil) LLAMSVERSELY <0. 8. 0. ce aS. wee eee eens eee ee ee cee see w4

Another specimen, consisting of the middle portion of an upper molar, from
its proportions and the folding of the enamel lakes of the triturating surface,
is supposed to belong to the same species. It was obtained in Navarro

County, Texas.

248

ig. 15 represents a specimen found in association with that of the pre-
vious figure of the same plate. It appears to be a third or fourth upper
molar, and, from the size and arrangement of, enamel on the triturating sur-
face, might be supposed to belong to the same animal as the former speci-
mens. In the proportions of the tooth it resembles those of Merychippus
more than it does those of Hipparion. ‘The crown is quite short, and exhibits
a considerable degree of curvature. It is about 2 lines long on the inner side,
and three times that length on the outer side. On the triturating surface the
antero-internal column appears as an elliptical ring, as in Hipparion, but it
exhibits a pointed process indicative of continuity at a later period with the
antero-median column, as in Protohippus and Merychippus. The tortuous
enamel-line on the inner part of the triturating surface presents no median
fold directed toward the elliptical ring, as is the case also in the fourth molar
of Protohippus, as seen in Fig. 2, Plate XVII, of the Extinct Mammalian
Fauna of Dakota, &e. ;

The antero-posterior diameter of the tooth is 72 lines, and its transverse
diameter 84 lines.

Another specimen, consisting of a mutilated, unworn molar, from its pro-
portions, is supposed to belong to the same species as the former. It was
obtained at a depth of 30 feet from the surface in Washington County, Texas.
The crown internally is 53 lines long, and has measured externally about 10
lines. Its breadth is 9 lines, and its transverse diameter has been but little
less.

PROTOHIPPUS (?!) s. MERYCHIPPUS?

Among the Texan collection of fossils there are several which are suspected
to belong to one or other of the equine genera above named,

Fig. 16, Plate XX, represents a specimen obtained from a well, at a depth
of 32 feet, at Independence, Washington County, Texas. It is an upper
molar, apparently the second or third of the series of the usual complement
of six large teeth in equine animals. In its proportions it would appear to
belong to the genus Merychippus rather thah Protchippus. The crown is
from 34 to 4 lines in length on the inner side, and from 7. to 8 lines on the
outer side. ‘The median enamel lakes of the triturating surface are of simple
character, and widely gaping, apparently indicating but comparatively little
wear, notwithstanding the shortness of the crown. In the appearance of the
triturating surface it resembles more the teeth of Protohippus perditus, as

249

represented in Fig. 2, Plate XVII, of the Extinct Mammalian Fauna of
Dakota, &c., than it does those of Merychippus, represented in Figs. 5 and 9 of
the same plate. On the other hand, it bears a near resemblance to the teeth
from Little White River, Dakota, represented in Fig. 1, Plate XX VII, of the
work just quoted, which were supposed to pertain to Dlerychippus nurabilis.

Another specimen, from Bastrop County, Texas, consists of an upper molar
with the portion internal to the median enamel lakes broken away. It is
rather smaller than the preceding, and would appear to hold the relation with
it in the series of a fourth or fifth molar.

A third specimen, accompanied by a label in the handwriting of Dr. Shu-
mard, is marked («Eocene,) Trinity River, Navarro County, Texas.” It is a
lower molar, represented in Fig. 20, Plate XX, and may perhaps belong to
the same species as the preceding.

The measurements of the specimens are as follows :

Lines. .
ame iieoteiie SCCOUG Upper MOP «6.2 ce as bie ee eh nei oe Seed eee eee ce oe 93
SMMMOMANe SeCONd TpPpPer MOlAL:.>.. 2 2e2 <5 bo sew we ees wore ee wee eae eee wee 104
PreioMot the fourth upper molar -...--...-2- 22 --n-s-eaee ee ceuee- 8
oe emUMMUMeTOWED MOAT. 0.05... kc enn es ois ea Seb ele wo eee e eee. eee 9
Mponmeomunelower molar. .....-2--0 <-2-- -- eee ae neces ee ee caee Fea mw co, OR

Fig. 17 represents a specimen found in association with those of Figs. 14,
15, at a depth of 25 feet, in Washington County, Texas. It is an upper
molar of the right side, probably the fourth of the series. It is but moder-
ately worn, and is imperfect at the back inner corner. In its proportions and
degree of curvature it agrees with the teeth of Protohippus. In size and
arrangement of the enamel it approaches in character some of those referred
to Protohippus placidus, represented in Figs. 39 to 48, Plate XVIII, of the
Extinct Mammalian Fauna of Dakota, &e.

The measurements of the specimen are as follows :

Lines.

Breadth of triturating surface... .-, ogc tbe Berh Ses MO Sb petebs Ab.) FeV News eas 74

Pen veTser(lamMoren Ol SUMACRE c-2.. 25-22) so-so ee ate eeee te be Seek eee ese sa 7

Fig. 18 of the same plate represents a specimen from “ Little’s Well,” 30

feet in depth from the surface, in Bastrop County, Texas. It is a first upper

molar, and is sufficiently like the former to belong to the same species. It
oa G

250

also resembles the corresponding tooth of Fig. 6, Plate XX VII, of the Kx-
tinct Mammalian Fauna of Dakota, &c., sufficiently to pertain to the same
species. ‘This specimen was obtained on Little White River, Dakota, and
was referred to Protohippus placidus. 'The proportions of the former are the
same, but, being more worn, it is shorter, and appears larger at the triturating
surface. At the same stage of abrasion they would even bear a greater
resemblance to each other, as the open fold on the posterior part of the Little
White River specimen, in a more worn condition, would then form an islet on
the triturating surface, as in the Texas specimen.

The measurements of the specimen, in comparison with those of the Little
White River specimen, are as follows:

Texas Dakota —
specimen. | specimen.

Lines. Lines.
Length of crown at the antero-internal column.....--..-...-..-- | 6 8
Length of crown at the postero-external column......-....-..--- 10 124
Breadth of crown at the triturating surface.......-.......-.---- 84 9
Width of crown at the triturating surface ...........-......-... 7 8

The Museum of the Smithsonian Institution contains several specimens of
teeth apparently of Protohippus perditus and Merychippus mirabilis, obtained
by Mr. Clarence King in Utah.

ANCHITHERIUM.
ANCHITHERIUM (1) AUSTRALF.

Among the Texan collection of fossils there is a specimen of peculiar
character represented in Fig. 19, Plate XX. It was found in association with
that of Fig. 16, of the same plate, in Washington County, Texas. It is’ the’
first of the series of six large upper molars as existing in equine animals, but
exhibits in front the impress of a premolar larger than usual in members of
the order. The specimen is broken at its outer part, but the remainder
is nearly as characteristic as if the whole were complete. The crown is so
worn away that the dentine is continuous upon all the constituent lobes. An
oblique valley extends from the inner side and ends in a foot-like expansion

‘near the center of the triturating surface, and back of the center there re-

mains a crescentic enamel lake.

251

The tooth is devoid of cementum, and resembles in its constitution the cor-
responding one of Anchitherium nearer than it does that of other known
equine animals. The inner and intermediate lobes appear somewhat fuller
than in Anchitherium, and the intermediate spaces narrower and less con-
vergent at bottom. .

It may perhaps belong to Anchippus, founded on an imperfect tooth from
the same locality, and represented in Fig. 13, Plate XXIJI, of the Extinct
Mammalian Fauna of Dakota, &c. It presents important peculiarities, but
these may depend on the difference of position of the tooth in the series.
There is, however, one feature in the tooth of Anchippus which is absent in
the specimen under consideration, rendering it probable that the teeth per-
tain to different genera. The feature to which I allude consists of a con-
spicuous fold or offset from the postero-median lobe projecting into the oblique
valley of the crown toward the antero-median fold. In Parahippus the same
fold exists in a more complex condition.

The tooth in question likewise resembles that represented in Fig. 11, Plate
XXI, of the work above quoted, as characteristic of the genus Hypohippus,
nearly as much as it does those of Anchitherium, and may, perhaps, belong
to a smaller species of the former.

In the uncertainty as to the nearer generic relationship of the specimen it
may be regarded as indicative of a species of Anchitherium with the name
given at the head of the chapter. The species was about as large as the
Anchitherium aurelianense of the Eocene Tertiary deposits of France.

The estimated size of the tooth is 11 lines in diameter antero-posteriorly
and nearly the same measurement transversely.

ANCHITHERIUM AGRESTE.

_ During Professor Hayden’s exploration in Montana, he discovered several
fossil jaw-fragments of a species of Anchitherium. They were found in asso-
elation with a Helix, partially imbedded in an indurated, gray, arenaceous
marl, and were derived from a lacustrine Tertiary deposit on Red Rock
Creek, one of the head branches of the Jefferson Fork of the Missouri
River.

The jaw-specimens belonged to a species considerably larger than the
Anchitherium Bairdi of tne Miocene Tertiary of White River, Dakota, and
approached in size the A. aurelianense of the Miocene Tertiary of France.

The teeth in the specimens, as represented in Figs. 16, 17, Plate VII, are
considerably worn, but retain their anatomical characters sufficiently to show
that they are identical in form with those of the two species just named.
They nearly accord in size with the mutilated upper molar, represented in
Fig 5, Plate II, from Oregon, referred to Anchitherium Condoni. Inthe doubt
whether the latter is really a true species of the genus in which it has been
placed, the lower-jaw fragments in question are regarded as representing a
species with the name heading the chapter.

Measurements from the specimens are as follows:

Lines.
Space occupied by the back tour molars: 25° = eee =e ees hee oe Be
Space occupied by the back three molars’...-. -.. 222.2220 7 2.2) 2 27
Fore and aft diameter, of last premolar....= ... <5:25.2:%. .-5-...-. Jee 8
Transverse diameter of last premolar. .-. >... ..-..-.025+--..2- 1.5) ee 63
Fore‘and aft diameter of first molar 2... .....--- 22-6. 422-6: -e 73
Transverse diameter of firsh molar... 2s... -~.----52 12-22 7
Fore and aft diameter of last. molar... .. -252 9-225-423-2215) 6. ee i
Transverse diameter of lash molar....-. |..--..-...).5)-).. 2) - 3

ANCHITHERIUM (‘?)

In digging a well at Antelope, Nebraska, in the summer of 1868, at the
depth of 60 feet a stratum was found which was stated to be remarkable
for the number of fossil-bones it contained. The relative age of the stratum
has not yet been ascertained, but from the character of the fossils it is sus-
pected to be contemporary with the Mauvaises Terres formation of White
River, Dakota, or perhaps with the later formation of the Niobrara River,
Nebraska. From among the specimens collected at the time, my friend Dr.
John L. Le Conte obtained a coronary bone of a small equine animal, which he
sent to me for examination.

The specimen was exhibited to the Academy of Natural Sciences, and is
noticed in its Proceedings for August, 1868. Subsequently, some remains,
apparently of the same animal, from the same locality were described by
Professor Marsh in the American Journal of Sciences for October, 1868, and
referred by him to a diminutive horse with the name of Equus parvulus.

The specimen of the coronary bone is represented in Fig. 23, Plate XX.
It is only a little over half the length and is considerably less than half the
breadth of the corresponding bone of the horse, so that it indicates an animal
of little more than half its height and of more slender proportions. Its
size would about accord with Anchitherium Bairdi of the White River

Tertiary formation of Dakota.

253

The measurements of the specimen are as follows:

; Lines
Iie MOG AIS pee epee tel ae ee sie od Pek Saree sw ee 9
eas MMab uM euUP MEL CXELEMIDY:: so-2) Sr ieee sles cis es yo be odie alerene as oe pee 9
MeanesspalnbMevlp Per OXGRCMNGY 222 20 228 ec stu wee bees bee Pee eae lee ERS. 6
Breadth at the lower extremity ...--......- Ey sec aha en a ee Re ins We cee DAS a 8

Order Ruminantia.

BISON.
Bison LATIFRONS.

Remains of large oxen which were contemporaneous with the American
mastodon have been discovered in several parts of North America. They
have been referred to several extinct species, but the materials have been too
incomplete to determine the question with any degree of satisfaction whether
they pertain to more than one. The fossils indicate individuals very greatly
differing in size, but the difference is perhaps sexual rather than specific.
The more robust specimens probably belonged to males, and the smaller
ones to females.

The most complete specimen which the author has had the opportunity of
examining is the cranium, retaining the horn-cores, represented in Figs. 4, 5,
Plate XXVIII, one-fifth the natural size. It was discovered by Mr. Calvin
Brown and his son Wilfred, of San Francisco, California, while engaged as
engineers in the construction of the Spring Valley water-works of that city,
and by these gentlemen was presented to the Academy of Natural Sciences of
Philadelphia. Mr. Calvin Brown informs me that the cranium was found
in a bed of blue clay, 21 feet below the surface, in Pilarcitos Valley.

The specimen resembles the corresponding part of the skull of the living
buffalo (Bison americanus) so closely that it will be unnecessary to describe it
in detail. Besides being larger, the horn-cores are especially dispropor-
tionately larger, and are more transverse in their direction, or are less inclined
backward. The occiput appears proportionately wider and lower from the
less degree of prominence of its summit. The latter is, however, wider,
and is more distinctly defined from the posterior occipital surface by the
rougher and more prominent protuberance of attachment for the nuchal
ligament. The occipital foramen is no larger than in the buffalo, and the
notch below, between the condyles, is more contracted. The forehead, near

its middle, is rather more protuberant than in the buffalo.

254

Comparative measurements of the fossil with the corresponding part of

the skull of a large buffalo are as follows:

Bison Bison
latifrons. | americanus.

Inches. Inches.
Distance between tips of horn-cores........-.----.+--.------- 36 26
Distance between bases of horn-cores ............-...---.---- 155 12
Circumference at bases of horn-cores../...2-..-.--------.---- | 14 Le
Length of born-core along lower curvature .....-...----.-..-- 145 12
Breadth of forehead where narrowest .-.. ....----..------..-- 134 11

Breadth of forehead at back of orbits ......-........--...-.--| 16 ~ 134
Length of forehead from occiput to fronto-nasal suture .....-.. | * 134 10
Breadthiofoceiput tc. Me Aaec me ce eres eyo etas auca satpate Seat | 125 10

Depth ohoceiputeee esse ee tS BI rae ee i 64
Breadth of condyles:tosethers: 527... > cee oes ne ee eee 6 5
Transverse diameter of occipital foramen........-.--..---.--.- ah 2

Vertical diameter of occipital foramen -............--.- Ae ADs 13 12

Distance between ends of paramastoid processes -....---.--.-| 5s 43

Length of temporal fossa-.-... = | 53 43

The California collection of fossils, belonging to the cabinet of Wabash
Coilege, Indiana, contains several specimens of teeth which I suppose to
belong to Bison latifrons. ‘They were loaned to me for examination through
the kindness of Professor E. O. Hovey, and are represented in Figs. 6, 7, Plate
XXVIII. They consist of the second and third upper molars, and agree in
constitution with the corresponding teeth of the recent buffalo, and in size
correlate with the skull above described and referred to B. datifrons.

The measurements of the specimens, in comparison with those of the
buffalo, are as follows :

Bison Bison
latifrons. | americanus.
Lines. Tines.
Second upper molar :
Antero-posterior diameter of triturating surface........--..-.--- 164 15
Transverse diameter of triturating surface ...........----..- E fat 102
Transverse diameter of crown near base..........---.---.---. 14 122
Third upper molar :
Antero-posterior diameter of triturating surface....-.-.-----.. 18 15
Transverse diameter of triturating surface........-......-.--- 10a 93
Transverse diameter of crown near base.-...........-........ 134 114

255

An isolated upper second molar of Bison latifrons, found in association
with remains of Mastodon americanus and Equus maor at Pittstown, on the
Susquehanna River, Luzerne County, Pennsylvania, is represented in Fig. 8,
Plate XXVIII. It is considerably worn, the usual median internal fold of
the tooth, in a less worn condition, being seen in the specimen as an
oval islet. .

The fore and aft diameter of the specimen is 164 lines, and its transverse
diameter at the triturating surface 12 lines.

A specimen of a last inferior molar of a Bison, represented in Fig. 4,
Plate XXXVI, and a metacarpal bone ef the Megalonyx Jeffersoni,
presented to the Academy by Dr. Edward. D. Kittoe, of Galena, were
obtained, together with some additional bones, from a crevice of the
lead-bearing rocks, at a depth of 130 feet from the surface, near
Elizabeth, Jo Daviess County, Lllinois. The tooth is about the size of
that of the recent buffalo, and may pertain to that species, though it is not
improbable it may have belonged to a small individual of Bison latifrons.

The specimen is but little worn. The length of the crown at its fore part
is 24 inches; its breadth 23 lines; its thickness at the base anteriorly 40

lines ; and near the triturating surface 7 lines.

_ AUCHENIA.
AUCHENIA HESTERNA.

In the Proceedings of the Academy of Natural Sciences for 1870, page
125, the writer described some fossil remains from California, submitted to
his inspection by Professor J. D. Whitney. Among the fossils were several
which were attributed to a large extinct llama, with the name of Auchenia
californica. 'The specimens upon which the species was founded consisted
_of a metacarpal bone, the fragment of another, the proximal end of a femur,
an acetabulum, and portions of a tibia. The species indicated was much
larger than the camel, as the head of the femur is 3 inches in diameter, and
the metacarpal is 19 inches long, whereas the latter in the camel is but 13
inches long.

In the Philosophical Transactions of London for 1870, Professor Owen
has described some remains of a large extinct llama from Mexico, under the
name of Palauchenia magna. This animal approximated in size the camel,
whereas the remains attributed to Auchenia californica much exceeded it.

Of the remains referred by Professor Owen to Palauchenia, there is a

256

series of molar teeth described and figured from casts and photographs. The
teeth are considered as pertaining to the lower jaw, but from a view of the
figures I cannot avoid the suspicion that they really belong to the upper jaw.
In the form and proportions of the molars, but especially in the form, consti-
tution, and number of the premolars, the series appears to me to resemble
more the upper one of the camel and llama than it does the lower one. In
one respect one of the molars, the last of the series, approaches in character
the last lower molar of the camel and llama. This is in the possession of a
fifth lobe, which is, however, much less well developed than in the latter
animals. If the view I have taken is not erroneous, Palauchenia, so far as
we know it from its remains, would not present sufficient distinctive char-
acter to be regarded as of a different genus from Auchenia.

Among the collection of fossils from California, belonging to the cabinet
of Wabash College, Indiana, there is a well-preserved series of lower molar
teeth, represented in Figs. 1, 2, Plate XX XVII. These, from their size and
constitution, would appear to belong to a species of llama exceeding in size
not only the existing llama, but also the camel and the Palauchenia.

‘The question at once arises whether these teeth belong to Auchenia cali-
fornica, Palauchenia magna, or to a third species.

The proportions of the bones upon which the former was founded indicate
an animal one-third larger than the camel, but the teeth above noticed might
belong to an animal but little exceeding a large camel or the P. magna. If
the characters assigned to the latter as a genus are correct, it is clear that
the series of teeth from California do not belong to the same animal, and they
then could only pertain to a small individual of Awchenia californica, or to
another species rather larger than the existing camel. Under the cireum-
_ stances, until further light is thrown on the subject by the discovery of addi-
tional material, we may suppose that two large species of llama, perhaps
exclusive of Palauchenia magna, were once inhabitants of the western por-

tion of the North American continent, contemporaneously with the Mastodon

americanus. One of these species, a third larger than the existing camel, is

the Auchenia californica; the second, intermediate in size to the two latter,
may be named A. hesterna.

The teeth in question indicate an animal which had arrived at maturity.
While the first molar, which earliest acquired its functional position, is much

worn, the last molar has its fifth lobe unabraded, and the premolar has but

partially lost its summit.

257

.

The molars show no characteristic differences from those of the llama and
camel. The narrow fold seen projecting outwardly in advance of the antero-
external lobe of the last molar, and in a less degree in the second molar, in
the llama, is nearly obsolete in the fossil.

The premolar presents some difference from the corresponding tooth in
the llama. The crown is thickest, and is rounded behind, and it narrows
forward to the anterior subacute, border; which is convex longitudinally, and
is thickened toward the bottom. The outer side is not impressed at the back
part, as in the llama, and is feebly. impressed at the fore and upper part. The
inner side also is but moderately impressed along the middle, compared with
its condition in the llama. A deep enameled pit occupies the inner back part
of the crown, penetrating from the triturating surface, as in the latter. The
pit opens backward for a considerable portion of its depth, and is closed in
this position by apposition with the succeeding tooth.

The measurements of the teeth, in comparison with those of the camel

and llama, are as follows :

Auchenia | Auchenia :
hesterna. lama. Camel.
Lines. Lines. Lines.
Fourth premolar:
* Breadth of crown where greatest ....-...-..--.-./.- 13 5S | 12
* Width of crown where greatest...............-..-- 6 2 7
Length of crown to origin of fangs.....-............-- 20 Guy 14
' First molar : |
ireadbhvor trituratine surface...............-...---- 20 “48 18
Maoun of triturating surface .-.....-..2....+..5.----. 105 5 9
TRE EP SMELL, ci clelad hci te cise see eb ge MeeVee eee’ 20 5 5
Second molar:
Poteaden OF triturating surface............ ...-.....-s. 26 9 "23
Memimnor tritirating surface ........................- 83 53 10
Width of crown where greatest............ gs is 10 52 10
“SW EN CHT LG RO? oe ee a 36 6 16
Third molar :
Breadth of crown where greatest: ....- - Beene ey ere at a 13 28
Myidth of crown where greatest.......-.........-....- LO) 5S 10°
SeePRUINOM CROW alae sae ec ob ek ele ce eee tas 41 7 7

“Vor brevity I have used breadth for the antero-posterior diameter, and width for the transverse
diameter.

aon

258

The length of the series of lower molars and premolars together, in the +

different species, is as follows:

Lines
Length of the series inthe Mamta 25 c2 cee oan eee ee eo. ee 32
Length of the ‘series\in the camel:.-<:-- 5... -.2 ones een ee 66
Length of the series in the Auchenia hesterna..........-.............-..--.--- 84

Accompanying the inferior molar specimens from California there is a
specimen of an upper molar represented in Fig. 3, Plate XX XVII, which,
from its constitution and size, is supposed to belong to the same species, if
not the same individual.

It is a first or second true molar of the left side, and closely resembles the
corresponding teeth of the lama.

Its comparative measurements are as follows :

Second upper molar. Tene Guar: Auchenia | Palauchenia
hesterna. magna.*
Lines. Lines. Lines. Lines.
Breadth of the triturating surface.......---. 93 20 234 21
Width of the triturating surface -......-.... Sis 11 12 113
Wadthiof-crown near base 522 --)-1-)-)- ee 8 13 143 |...
Lenethroticrowny 2h esnac ne eker seers 64 10 29 163

* Professor Owen’s measurements given as those of the second lower molar.

PROCAMELUS.

The genus Procamelus, or Protocamelus, was originally named from remains

discovered by Professor Hayden, in the Tertiary sands of the Niobrara River,

Nebraska. Three species were indicated from the locality under the names
of Procamelus robustus, P. occidentalis, and P. gracilis. 'Yhe specimens show
that Procamelus possessed a series of four premolars and three molars to the
lower jaw, from which we may infer an equal number to the upper jaw. The
molars and last premolar have the same form as those of the camel.

Among the Texan coliection of fossils, loaned by Professor Buckley, there
is a specimen of a tooth supposed to belong to Procamelus. It is repre-
sented in Fig. 21, Plate XX, and was found in association with the equine
teeth before described, and represented in Figs. 14, 15, and 17 of the same
plate. It is a first or second upper molar, and sufficiently resembles the

corresponding tooth of P. occidentalis, as we may suppose it would appear in

——

259

the same stagé of wear, as to render it probable that it may belong to the
same species.

The tooth is much worn, leaving two narrow crescentic enamel pits in the
middle of the triturating surface. No trace of an internal column or tubercle
exists in the interval internally of the inner lobes of the crown.

The specimen measures 11 lines antero-posteriorly, and nearly the same
extent transversely.

Fig. 22 represents an astragalus found in association with the molar tooth
just described, and probably belonging to the same animal. It has nearly
the size and form of those of the common deer, but is proportionately a little
longer and narrower.

Another specimen in the same collection consists of a cubo-navicular bone
of a ruminant a fourth smaller than the common deer. It was found in asso-
ciation with the equine tooth above described, and represented in Fig. 16,
Plate XX.

An additional specimen consists of a last lumbar-vertebra, apparently of a
ruminant. It was obtained in Washington County, at a depth of 30 feet,
from a hard arenaceous limestone. It is white in color, crushed downward,
and has a portion of the matrix adherent. The vertebra has nearly the size
and form of the corresponding bone of the camel, and may have pertained to
the largest species of Procamelus, named P. robustus.

PROCAMELUS VIRGINIENSIS.

I may here indicate the recent discovery of some remains, apparently of a
species of Procamelus, in the Miocene Tertiary formation of Virginia, the
first which have yet been noticed of the family in any locality east of the
Mississippi River.

Mr. C. M. Smith, of Richmond, Virginia, while engaged in excavating a
tunnel beneath the city, discovered a number of bones and teeth, which he
has loaned to me for investigation. They were found imbedded in blue clay
containing numerous infusorial remains, among which the beautiful frustules
of a Coscinodiscus are especially conspicuous. The fossil-bones mainly
consist of those of cetaceans and fishes, but among them are a few of
land-animals, and also a portion of a humerus of a bird. The forma-
tion from which the fossils were derived is probably an estuary deposit of
Miocene age. Among the fossils there are several teeth, which are sup-

260

posed to belong to a species of Procamelus. The specimens, consisting of a
last premolar, and the first and last molars of the lower jaw, are represented
in Figs. 26 to 29, Plate XXVII. The teeth have the same form and consti-
tution as those of the western species of ‘Procamelus above named, and they
appear to indicate an additional species, which was about the size of the ex-
isting llama, and intermediate in size to P. occidentalis and P. gracilis

The measutements of the teeth are as follows: :

: : Lines
Antero-posterior diameter of last premolar........-2-:-----..----- «eee 7
Transverse diameter of last premolar .....-.. 222s a, 4
Amero-posterior ‘diameter of first molars: /-)-/)-=.-i- 9 le ee a) 4 = eee 1Z
Transverse diameter of first molar. ....3-.--2..--.2+.-0--55. 2-250 6
Antero-posterior diameterot last molars... .2-- bee ie eee MPA Sir = 2 ‘123
Transverse diameter of last molar ....--......--.-.-:- cits. S$, ene aids See 6

MEGALOMERYX.

MEGALOMERYX NIOBRARENSIS (2)

The genus to which the above name was applied has not been determined
by positive characters, and may prove not to be distinct from Procamelus.
It was proposed on two specimens of teeth of a large ruminant, apparently
of the camel family, discovered by Professor Hayden in the Pliocene Tertiary
sands of the Niobrara River, Nebraska. The teeth, both lower molars, are
described in the ‘‘ Extinct Mammalia of Dakota and Nebraska,” page 161, and
are represented in Figs. 12-14, Plate XIV, of that work.

A similar tooth was submitted to my examination, by Professor J. D. Whit-
ney, from the Pliocene Tertiary of Tuolumne County, California.

Figs. 24, 25, Plate XX VII, represent a mutilated lower molar, apparently
of the same species. This was found in L’Eau qui Court County, in Northern
Nebraska, and was presented to Swarthmore College by George 8. Truman.

CHELONTA.
EMYS.

EiMYS PETROLEI.

An extinct species thus named is indicated by a number of fragments of
several turtle-shells, which were found in association with remains of Masto-
don, Megalonyx, Equus, Trucifelis fatalis, &c., in Hardin County, Texas.
They were obtained from a stratum of clay beneath a bed of bitumen, and,

261

like most of the other fossils accompanying them, are thoroughly saturated
with bitumen.

The most characteristic specimens consist of two isolated episterna, repre-
sented in Fig. 7, Plate IX. They indicate an animal about the size of the
recent Eimys scabra of the Southern States, but the bones are proportionately
moré robust than in that species. They abruptly project in advance of the
lateral grooves defining the gular scutes, and are squarely truncated. The
upper gular surface is nearly square, and slopes forward to an acute edge.
In one specimen it is wider fore and aft than transversely; in the other rather
less. Behind the gular surface, the bone is deepiy hollowed into a concavity.

The measurements of the specimens are as follows :

Lines. Lines.
', Width of episternal at the front border...... .... ...4.-.- aay pean 11
Wenernot internal -border.....5-..-2..4 02202-2250... Bl ike pets 32 | 12 14
Meueiieon postero-lateral border ...-..-.---------2---+-+8 222-2. re 15
Greatesp puckness of the bone.-. -.-.....-.:.---------- Ae cee 54 54

A hyposternal bone about the middle is 28 lines fore and aft, 26 lines wide
behind the inguinal notch, and half an inch where thickest internally.

The fore part of a nuchal plate of the carapace resembles the correspond-
ing portion in Emys scabra, but is more deeply indented. Its width in front
is an inch; the length of its median ridge is 103 lines; and its thickness where
greatest is half an inch... :

FISHES.

The following species of extinct fishes were first described by the writer
m the Proceedings of the Academy of Natural Sciences of Philadelphia for
June, 1870. The specimens were borrowed for my examination from a
gentleman of New York, by my friend Mr. George N. Lawrence, of the
same city. The locality of the specimens was not ascertained other than
that they came from the Rocky Mountains. They were accompanied with
some shells, evidently of the later Tertiary period, and also with a coronary
bone, apparently of Equus excelsus. The fish-remains consisted of eight *
detached pharyngeal bones’of a cyprinoid. and a single dermal bone of.a ray.

Subsequently, while a notice of these fossils was in press, the writer
received from Professor Hayden a pharyngeal bone of the same species and

appearance as the former, which was labeled “Castle Creek, Idaho.”

262

More recently, Professor J. S. Newberry sent to me a small collection of
fossils, among which were seven additional specimens of pharyngeal bones,
identical in appearance with the former, which were stated to have been
found at Castle Creek, Idaho.

Later, Professor Cope described, in the Proceedings of the American
Philosophical Society, a number of species and genera of extinct cyprtnoid
fishes from Catharine’s Creek, Idaho. Among these he indicates the same
species as that to which the above-mentioned pharyngeals have been
attributed, and which have been referred to a previously undescribed genus,
as. follows :

Family Cyprinidae.
MYLOCYPRINUS.
MYLOCYPRINUS ROBUSTUS.

The specimens, consisting of detached pharyngeal bones with teeth, from
which the genus and ‘species were originally described, were all imperfect.
Having attempted the description without a previous comparison with the
corresponding bones of a recent cyprinoid, I find I have been so careless as
to have described them in an inverted position. The specimens later received
are better preserved, and among them are five complete ones. All the
specimens together exhibit such a variety in size and detail as to lead one to
-suspect they may represent several different species, though I view them as
belonging to a single one, the differences being, as I suppose, mainly due to
a difference of age. Six specithens, from Professor Newberry’s collection,
are represented, of the natural size, in Figs. 11 to 17, Plate X VIL, all of them,
excepting Fig. 16, being views beneath with the back part directed upward.
Fig. 16 represents an inner view, exhibiting the masticatory surfaces of the
teeth.

The principal row of teeth consisted of five, as may be seen by the organs
themselves and their remaius in Figs. 11 to 14, inclusive. They are all of
the true masticatory type, and are directed inwardly, opposed to those of the
other side. The first and last of the series are the smallest, and the inter-
mediate ones are comparatively large.

In the smallest specimens, and the youngest, as I suppose them to be, the

second tooth is the largest, and from this they successively decrease in size

263

to the last, as seen in Fig. 13. In the largest and oldest specimens, the in-
termediate three teeth are nearly equal in size, as seen in Figs. 16, 17. In
the specimens of intermediate size and age we notice some irregularity, but
generally a disposition to increasing uniformity of size in the corresponding
teeth. ae

The first tooth is directed backward toward those behind; the others are
parallel in their direction inwardly.

The crown of the terminal teeth is more mammillary than in the, interme-
diate ones, in which it is oval with the longer diameter directed from above
downward, and the short diameter fore and aft. The masticating surface of the
teeth is broad, oval, moderately convex, sometimes nearly flat, and usually
slightly depressed at the middle or at the center. The crowns resemble
strikingly those of worn human premolars, and are covered by thick, smooth
mameloid substance. : ,

The teeth are supported on strong bony columns as long as the crowns
‘They project from the lower ramus of the pharyngeal below the position of
the upper or posterior ramus. The last of the series projects backward and
inward from the conjunction of the two branches, as usual in cyprinoids.

In the older specimens, it would appear that the first tooth of the series
was after a certain time not replaced.

Most of the specimens present evidences of -the existence of two minute
teeth forming a second row above the principal one. ,

The pharyngeal bones, in accordance with the strong crushing teeth they
sustain, are stronger than usual in the ordinary living carp-like fishes.

The pharyngeal bore is-widest opposite the larger teeth. The oblique
surface directed forward and outward exhibits the usual deep hollows extend-
ing to the bases of the teeth, or through the bone in some cases when thie
latter are absent or shed. The posterior and inferior surfaces are flat, and
transversely striated, or, in the older ones, more or less strongly ridged. The
anterior border is vertically concave. The external border, acute below and
obtuse behind, is unusually thick. The inner border, extending backward
beyond the conjunction of the two branches of the bone, is that which sus-
tains the teeth.

The upper or posterior.ramus is comparatively short, bent forward and
inward, and ends in a point by which it was suspended from the occiput.
The extremity of the lower or anterior ramus, extending in advance of the

264

teeth, ends in a triangular process with w lozenge-like articular surface for
. ~ . . . *.
symphysial attachment with the bone of the opposite side.

Measurements derived from seven specimens are as follows:

Measurements. Spec. 1.|Spec. 2.| Spec. 3. Spec. 4. Spec. 5.| Spec. 6.| Spee. 7.
Lines. | Lines. | Lines. | Lines. | Lines. | Lines. | Lines.
Tuength oftseries of five teeth: -<..)Sa\t —. Sue ee ae leeeeeel eee |) 2
Length of series of four teeth, exclud-
TEE GE GPS Gi. 2.) = ceva speeiae eee dG eg F2 94 9 6 6 |- 5
Length of series of intermediate three
beeth ss... Se eae eee eee es 12 10 8 1 \oso 4
Length of series of anteri TOT GATES GECURE eaten eee ds cD a ee ne
Long diameter of crown of first tooth..|..:...|".----|::--..].--..- 14 1 oye
Long diameter of crown of second tooth. 44 44 33 3 24 24 24
Short diameter of crownof second tooth. 33 | ~34 23 24 | ° 2 2 14
Long diameter of crown of third tooth.|...... 44 44 3d 24 | ~2 13
Short diameter of crown of third tooth.)...... 34 23 24 2 1} 14
Long diameter of crown of fourth tooth.) - 5 44 4 3. | Aero 13
Short diameter of crown of fourth tooth. 34 3 24 2. 122 1
“Long diameter of crown of fifth tooth.|...... B |cemenlos'e-2eleneee eee 1
Short diameter of crown of fifth tooth.|...... 2 olsen cee | sae doa ee 2
_ Length of lower branch from back of :
pharyngeal. 23228. sseee se cee 7 DAR TOF ale iAlia, 16 14 ahi! 103
Depth of upper branch to bottom of
pharyneeale tree ms cece ree A eae Sea Semen TO. | 2 os eee
Width of pharyngeal inferiorly.» .... - 14 AP US eo?) 8$ 8 7

* Estimated.

Family Rae.
ONCOBATIS.

ONCOBATIS PENTAGONUS.

An extinct ray, before alluded to, is indicated by a single dermal bone, of
which two views are given, of the natural size, in Figs. 18, 19, Plate XVII.
The bone has a pentagonal outline with curved margins, with the under or
inner surface strongly convex and smooth. The upper or free surface presents
five sloping planes more or less well defined by prominent borders.- Less
than half the extent of the external surface at the center is occupied by an
areola of thin enameloid substance which is smooth and shining and marked
with concentric lines. The summit of the bone, inthe center of the areola,
projects as a point of harder and more translucent osseous substance.

ee)

The measurements of the specimen are as follows:

id Lines
Greater diameter of the dermal bone ...-..... . Ne sa AN albino ad ati, Oe Nie
Shonuer diameter of the dermal bonevss!2...--..62..0¢ 5022-22224. eee ee enon ee 15
Minekmessdronl SUMMIb..2 0266 Loo. oh es 2 Se ek pea ae: EES we PEE s RE Ue tes 8

The many more fossil-remains of fishes from the Tertiary formation of
Idaho, described by Professor Cope, he attributes to two additional species
‘of Mylocyprinus, seven species of four other~ genera of Cyprinide, and a
species of Salmonide. Fossil-shells described by Mr. Meek from the same
formation, as well as the cyprinoid fishes, indicate a fresh-water deposit. The
presence of a ray may probably indicate an easy communication with salt

water.
oa

DESCRIPTION .OF REMAINS OF REPTILES AND FISHES FROM
THE CRETACEOUS FORMATIONS OF THE INTERIOR OF THE
UNITED STATES. .

The Cretaceous formation in the interior of the United States covers an
area reaching southerly into Texas, and extending over a large portion of the
eastern slope of the Rocky Mountains, northerly along the region of the
Upper Missouri River to its sources. Exposed to view over a great extent.
of this area, a still larger portion underlies the vast Tertiary deposits of the
country. Its thickness ranges from 800 to 2,500 feet, and it consists of
various colored strata of indurated clays and sandstones, and indurated marls
and limestones. So far as known, most of them are of marine origin, and
contain an abundance of characteristic fossils. Some of the strata con-
tain remains of terrestrial plants, proving that the country in the vicinity of
the great Cretaceous seas was clothed with forests resembling, in the generic
characters of the trees, the forests of our own time. Species of sweet-gum,
poplar, willow, birch, beech, oak, sassafras, tulip-tree, magnolia, maple, and
others have been described from the fossils. With such a vegetation we
would expect the contemporaneous existence of some forms of mammalian
life,.but as yet, in these as well as in other Cretaceous deposits of the world,
no remains of mammals have been discovered. We are, however, still on
the lookout for some lacustrine or river deposit of the Cretaceous era which
perhaps will reveal early forms of mammals—forms which may more nearly
relate the mammal with the reptile than any now known to us.

Remains of birds: have been found in the Cretaceous formation of Kansas,
and have been described by Professor Marsh. ‘T'wo genera indicated by him
under the names of Ichthyornis and Apatornis are the most remarkable of
. their kind, and may be viewed as the most interesting and important paleon-
tological discovery yet made in the West. They have biconcave vertebre,
and the jaws are furnished with teeth. Like the Archzeopteryx of the Solen-_
hofen limestone, they make the relationship of birds to reptiles much nearer

than appears among existing forms.

267

In remains of reptiles and fishes the western Cretaceous formation abounds.
Many of these have been described by Professor Cope and Professor Marsh.
Among the reptiles are some of the largest and most wonderful of their kind,
represented by great turtles allied to Atlantochelys; numerous species of
Mosasaurus and closely related genera; the Polycotylus and the long-necked
Discosaurus allied to Plesiosaurus; and Pterodactyls, with an enormous
expanse of wings. ; ;

The following pages contain descriptions of remains of reptiles and fishes
which have come under the observation of the author. mainly from the west-
ern Cretaceous deposits. A few of the remains are doubtful as to the forma-
tion from which they have been derived, but are believed to be Cretaceous
fossils. As intimately related with the western Cretaceous fossils, descrip-
tions of a few others are included from eastern localities.

Most of the fossils were submitted to the examination of the author by the
Smithsonian Institution, and: form part of a collection from the Smoky Hill
River, Kansas, and from the Indian Territory, presented to the Army Medical
Museum of Washington by Dr. George M. Sternberg, United States Army.
Others from the Smithsonian Institution were collected in the vicinity of
Fort McRae, New Mexico, and were presented to the Army Medical Museum ~
by Dr. W. B. Lyon, United States Army. Many of the fossils were collected
during the explorations of Professor Hayden. The remainder form part of
the Museum of the Academy of Natural Sciences and Swarthmore College,
or have been contributed by Dr. William Spillman, Dr. John L. Leconte,
Professor George H. Cooke, William M. Gabb, George H. Truman, and
others. .

His Did gd he Id gee

Order Dinosauria.
POICILOPLEURON.
PoIcILOPLEURON VALENS.

During Professor Hayden’s expedition of 1869, a fossil was given to him
as a ‘‘ petrified horse-hoof.” The specimen was found in Middle Park, Col-
orado, and according to Professor Hayden was probably derived from a forma-
tion of Cretaceousage. Similar specimens were reported not to be uncommon,
and were known as above designated. Indeed the writer has seen a second
specimen, which was also called a fossil horse-hoof, but unfortunately his
notes in relation to it have been mislaid.

268

The fossil in question consists of one-half of a vertebral body as repre-
sented in Figs. 16 to 18, Plate XV. When resting upon the articular face,
it is not surprising that it should have been taken for a “petrified horse-
hoof” by those not conversant with anatomy.

The vertebral body in its entire condition would resemble in form those of
Megalosaurus, and in shape and other characters resembles those of Poicilo-
pleuron Buckland. ‘This is an extinct reptile, from the Oolitic formation of
Caen, Normandy, described by M. Deslonchamps; and remains apparently
of the same animal, from the Wealden formation of Tilgate, England, have
been noticed by Professor Owen. It has been viewed as a crocodilian, and
is estimated to have been about 25 feet in length.

The Colorado fossil would indicate an animal approximating 40 feet in
length.

One of the most remarkable characters of Poicilopleuron is the presence
of a large medullary cavity within the bodies of the vertebrae, as well as in
the long bones of the limbs. Among living animals I know of a similar con-
dition in the vertebree of none except in the caudals of the ox. This curious
feature is a striking one in the Colorado fossil, as represented in Fig. 18.

The lower two-thirds of the body appear occupied by a large cavity, crossed °

by a few osseous trabeculae. The cavity is bounded by a thick lateral and
inferior wall of compact substance, resembiing that of the shaft of the long
bones of most mammals. The wall is about 2 lines thick, and thins away
at the upper part of the body where this is occupied by the ordinary spongy
substance. The latter extends into the abutments of the neural arch, and is
here more dense in character. The cavernous structure of the fossil is filled
with crystalline calcite.

The estimated length of the vertebral body.is about 6 inches. At the sides
and beneath it is much constricted or narrowed toward the middle. The
transverse section approaching the latter position is vertically ovoid, with the
lower and narrower end forming an acute angle.

The articular end of the specimen, Fig. 16, is moderately depressed its
greater extent, most so above and becoming more superficial below. Its
upper border overhangs the deepest portion of the surface; the lateral bor-
ders are obtusely rounded, and widen below in a strongly convex ledge, prob-
ably for the accommodation of a chevron bone. The breadth of the articular
sutface is nearly 4 inches; its vertical extent a little over that measurement.

279

The abutments of the neural arch are firmly co-osified with the body, but
their sutural connection is plainly visible. Just below the suture, the side of
the bod¥ presents a concavity. The beginning of a groove or narrow con-
cavity is also seen extending forward beneath the body. The lateral surfaces
of the specimen are smooth, excepting near the everted articular border of
the body, where they are roughened for the firmer attachment of ligaments.

Poicilopleuron was probably a semi-aquatic Dinosaurian, an animal equall¥
capable of living on land or in water, and perhaps spending most of its time
on shores or in marshes. Whether the cavernous structure of its skeleton
was related to pneumatic functions, as in birds, flying reptiles, and some
others, or whether it was only occupied with ordinary marrow, is a question
that appears uncertain while our knowledge of the skeleton itself is so

incomplete.

Order Chelonia.

Among Dr. Sternberg’s collection of fossils from the Smoky Hill River,
Kansas, there are several which appear to be the limb-bones of a turtle.
Similar bones from the Cretaceous formation of New Jersey and Mississippi
I formerly attributed to species of Mosasaurus, but the recent discoveries of
characteristic portions of the skeleton of this and allied animals, retaining
the limbs, have proved that view to be erroneous. .

A huge turtle, represented by the proximal extremity of a humerus found
in the green sand of gNew Jersey, was named by Professor Agassiz Atlan-
tochelyssMortom. Professor Cope has described some remains of a species
nearly as large as the former, from Kansas, under the name of Protostega
gigas; and an arm-bone of a smaller turtle, from the Cretaceous formation
of Mississippi, he has referred to a species with the name of P. tuberosa.
Remains of a turtle, about the size of the Mississippi snapper, from Kansas,
he has attributed to another genus with the name of Cynocercus incisus. The
specimens of limb-bones above mentioned, and represented in Figs. 17 to 21,
Plate XXXVI, are not large enough to pertain to the smallest of the three
species of Atlantochelys indicated, but would sufficiently relate in size with
the remains of Cynocercus incisus to belong to that animal.

The bones appear unusually flat, but this condition, in part at least, is due

to compression. . .

Fig. 17, Plate XXXVI, represents the upper extremity of a humerus

270

extending to the commencement of the distal expansion of the shaft. It
resembles nearly the corresponding portion of the humerus of the snapper
completely flattened, or a miniature of that of Atlantochelys in the same con-
dition. The greater tuberosity appears to spring from above the top of the
head externally, so that its upper anterior border looks like an extension of
the articular surface of the latter. A strong muscular impression is situated
upon the inner fore part of the shaft. The lesser tuberosity ‘projects bic
riorly, and ends in a thick, roughened, convex surface.

The breadth of the specimen between the two tuberosities obliquely meas-
ures 33 lines; the breadth of the shaft, where narrowest, is 10 lines.

Fig. 18, represents a complete femur, apparently from the same individual
as the former. As in the snapper and Trionyx, it is of proportionately less
breadth than the humerus. It is apparently much flattened by pressure, so
as to differ considerably from its exact original form. The trochanters appear
relatively to have been as well developed as in the snapper, and the distal
articulation may be supposed to have had nearly the same form.

The length of the femur is 54 inches. The breadth of the upper ex- -
tremity is 20 lines, of the lower extremity 16 lines, and of the middle of
the shaft 7 lines.

Several additional bones accompanying the former appear to belong to the
shoulder of the same animal.

Fig. 19, represents what appears to be a portion of the left scapula with its
upper end and the prae-coracoid prolongation broken wy. The specimen
appears distorted and flattened from its normal condition as the result of
pressure.

Fig. 20, represents what appears to be a portion of the coracoid bone of
the same side, also somewhat distorted by pressure.

Fig. 21, represents another bone-fragment, apparently from the same indi-
vidual, which I cannot determine to my own satisfaction. Like the other

specimens, it appears flattened from its normal condition.
Order Mosasauria.

Large, extinct, marine saurians, most nearly constructed as in Lacertilians,
but having limbs constructed as paddles for swimming. ‘The relations of these
reptiles with the serpents, as suggested by Professor Cope, in his Synopsis of
the Extinct Batrachia, Reptilia, &c., have been much reduced by the subse-

271

quent discoveries of Professor Marsh; and they appear hardly sufficient to
justify the name of Pythonomorpha. :

The remains of mosasauroid reptiles are comparatively abundant in the
Cretaceous formation of the United States. The specimens collécted have
formed the basis of a multitude of species and genera, the number of which
will probably be somewhat reduced on more careful study and comparison of
the materials. j .

In the description of the few mosasauroid remains which have been sub-
mitted to my examination, I have referred them to species for the most part
as recently named by Professor Marsh, who, with the rich materials in his
possession, has the best opportunity of determining their generic and specific

characters.
TYLOSAURUS.

TYLOSAURUS DYSPELOR.

Among the fossils submitted to my examination by the Smithsonian Insti-
tution, there are some bones of a large mosasauroid animal, collected by Dr.
W. B. Lyon, United States Army, in the vicinity of Fort McRae, New Mexico.
They consist of vertebrae, mostly more or less crushed and otherwise muti-
lated, and a few limb-bones, and were obtained from a stratum of soft, yel+
Jowish chalk. Specimens from the same collection and skeleton were de-
scribed by Professor Cope, and referred to a species with the name of Liodon
dyspelor. This was subsequently referred to a genus, by Professor Marsh,
with the name of Rhinosaurus, which, being pre-occupied, Professor Cope
proposed that of Rhamphosaurus, and, as this also was previously appropri-
ated, Professor Marsh has now proposed the name of Tylosaurus.

Of the specimens selected by me for examination half a dozen consist of
centra and parts of others of posterior dorsal vertebra, most of which are
remarkable for the extent of compression they have undergone with little
appearance of fractures. They look as if they had been in a plastic condi-
tion, and in this state had been flattened from above downward.

In three of the specimens, consisting of posterior halves of dorsal centra,
the articular ball presents a half oval outline below, with slanting sides above,
and an emarginate summit. The measurements of the ball, indicating a suc-
cessive increase in the degree of flattening in the three specimens, are as

follows:

272

Lines.

Depth of specimen represented in Fig. 1, Plate Ke, cL Star” ahi oe 44,2
Breadth of specimién*>.... oN225 oie ee ee ee ee ee ae ene ee ae 60. 0
Depth of second Specimen 2.22 42257 sb) -2etccoe eae here nore ta fools ee 42.0
Breadth,of, second specimen so. ices ret as ps ee eee ee ease te --. Sei
Depth. of specimen represented In Wig! 2 ones ie eens a cee Ree eee ieee 39.8
Breadth ‘of specimen ..5 .. )2!s255 22 Bis SORES IS ele eee eee 63. 0

In the other three specimens, consisting of nearly complete dorsal centra,
and measuring about 44 inches in length, the compression is still greater.
In one of the specimens the distal articulation, represented in Fig. 3, is so
flattened as to appear transversely lenticular in outline and emarginate above.
It measures 30 lines in depth and 624 lines in breadth.

Seven selected specimens consist of caudals which have mostly undergone
little or no compression. They all present beneath a pair of strong processes ©
projecting obliquely backward from nearer the: posterior part, and excavated
in a conical pit directed backward and downward for articulation with chev-
rons. Three have been provided with strong diapophyses projecting in
advance of the middle and nearly half way up the’sides. A fourth specimen
has a small, narrow diapophysis projecting in advance of the middle and
about two-thirds up the sides. The remaining two vertebre have no dia-
pophyses. : |

The caudals with diapophyses have the articular ends of the body trans-
versely oval, with a slightly hexahedral outline, emarginate above, and in a
less degree below. Those without diapophyses have the articular ends of
proportionately less width, of less hexahedral outline, and not emarginate
below, so that they appear more cordiform than oval.

The largest caudal with diapophyses has measured as follows:

Lines
Estimated length of centrum beneath ..... eee ns 2 - 37.5
Estimated breadth of artienlarends-.- ..--:..-22--2----- 5--e=- = 48. 0
Depthofurtieularcendss. 2) soe osoee ees. eee Bittle teach Se 42.0

A smaller caudal with diapophyses, less mutilated, and represented in Figs.

4, 5, measures as follows:

Lines
Length of centrum beneath.........- a eee beat ae Sashes. 0 eee 298.5
Breadth ot articular endSeu... 224 o5-2 2! ae. fase ee es oe ee ee ee 44,0
Depth of articular ends.......- SSO ee Sao oer Se ere ee Eee 40. 0

The caudal with small diapophyses, represented in Figs. 6, 7, measures as
follows :

Lines
Menanimoicentrumirbenedth:. 2. 2k. ots.. 225... 8c ie eee 30.0
PoE OMUNGMaGie Waly CMOS. 2-7 .)o6 = whe bon sis Cw nae eae peste e dens ge sae wdea ges 40. 5
TE ven CE PATE BTN 2 TES 000 IS Se oe eT a 36. 0

The better preserved of the caudals without diapophyses, represented in

Fig. 8, measures as follows:

Lines
Length of centrum beneath.....-...... Sele BE Syne SESE aa: ae 24
eee ME Oe alile Ullal CMOS 2m ae rhe Mee Met) Gets Sahel ia Gee nee o UNS Seb ese's ules = + 38
Mee aL hI CULAR CNICS<cie e cnc ys piel Selon vee ete cle eee eee LING ea 36

The researches of Professor Marsh have proved the mosasauroid reptiles
to have had four limbs constructed as paddles and adapted to swimming.
Previous to his discoveries it was supposed that posterior limbs were absent.

Specimens of limb-bones, found in association with the vertebral specimens
above described, are supposed to belong to the posterior limbs, from the latter
pertaining to the back part of the column.

The femur represented in Fig. 9, Plate XX XV, is a broad bone strikingly
different from the humerus of Clidastes. The specimen is probably more
flat than in the normal condition, as its many fractures are evidences of its
having been crushed.

The distal extremity is much the wider, and the upper extremity is but
little wider than the shaft. The head appears as a wide, lenticular, convex,
and very rugged surface. The lower extremity ends in a long, narrow, ellip-
tical, rugged surface for articulation with the bones of the fore-arm. From
the posterior part of the shaft there projects a thick, convex ridge, which
terminates above in an oval, flat, rugged surface, sloping from that of the
head of the bone.

The rugged, articular surfaces of the femur would appear to indicate a
cartilaginous continuity with the contiguous bones more intimate than in
Clidastes.

The measurements of the specimen are as follows:

Lines
PPCM MRL SoTIMUne Mere a Riettcle Rickais aic\c siejavw a/ewGimnlclaicic vaiale sani seis miea a\cigie e's einte'e sis. 96
ema MUNN ONE em ie armenia Wala als sila oe pieraina Se we Senin nn oR enh a wns ees cis = 464
iereadtnh of distal extremity....-.--. .-..-.2..----..5---5- PS Oia i Cae ce 69
iEereatuooat narrowest part of shaft ......-..-- 42. 5- ele wee eee eae c ee eee Bone ah 34
Mirckness ob head and trochanter .............--:..-+.-.0--2t2 ese. - +--+ es 28
Greatest thickness of lower extremity... .- Reh he or Seen io MEE 8 Fic 5 17

The remaining two bones I take to be those of the leg, though I am

uncertain in regard to their relative position with each other and the femur.
3D G

274

The specimen represented in Fig. 10 I suppose to be a fibula, though it may
bean ulna. It is a broad bone, almost as wide as the femur, but not so long.
Tts flatness has been somewhat increased by pressure. The upper extremity
presents a wide, lenticular, uneven, convex, and roughened surface for carti-
laginous union with the femur. The lower extremity presents a similar sur-
face, but wider and of less depth or thickness.

The measurements of the specimen are as follows:

. Lines
Length of fibula -..... 22 223. a2 wo-4) eeees Melee wee ese 66
Widthcof upper extremity te. 72-. see. ses ee -beeeetes tone oe 54
Thickness of apper extremity »..222.26 inh -6 02h 2 tee - Ee er 21
Width of lower extremity, partly estimated ..... eee 65
Thickness of lower extremity ...-.-6-- .-2 6 ste ee oe es coe ey = rr 17
Width of shaft near middle... 2005 Noll 22. a2. Sa 38
Thiekness, of shah. 22:0 -)j20 else. se ina th ce cleterd Teh bya ets ds 4 = 13

The supposed tibia, represented in Fig. 11, is a much smaller bone than
the fibula. It is clavate, with the lower extremity the more expanded and
thinner. The upper part of the shaft is compressed cylindroid, and becomes
wider and more compressed below. The upper extremity presents a trian-
gularly oval, slightly convex, articular surface, rugged as in the other bones.
The lower articular surface is transversely convex and widely lenticular.

The measurements of the specimen are as follows :

Lines
Léneth of the tibiais.% 65 442 agelnch ens 2. web ese ed eee 45
Width of upper'extremity :...5...2652 242 o¥5,6s suc teaees a. 3 er Pak
Thickness of upper extremity --....--.-. te wg te ia SE wh
Width of lowerextremityis..22/4) at foe Sa Oe ere ee Det! oc 34
Thickness :of lower extremity --...-2.--.-5.-¢2.-ee.-2---= - 22 se 11
Width of narrowest part of shaft.-...............-- bad vaechs dele 12
Thickness of narrowest part of shaft...0 J...+-s2 Sie.) 222) Eee 1244 AO

'TYLOSAURUS PRORIGER.

Dr. Sternberg’s collection of Kansas Cretaceous fossils, preserved in the
Museum of the Smithsonian Institution, contains specimens pertaining to
several individuals of a large Mosasaurus-like reptile, approximating in size
the Maestricht Monitor of Europe, and the Mosasaurus Mitchell. of New
Jersey. The specimens appear to pertain to the same animal as that de-
scribed by Professor Cope under the ames of Macrosaurus and Liodon pro-
riger, and afterward, as in the case of the former species, referred to another
genus by Professor Marsh, under the name of Rhinosaurus, then by Professor

275

Cope to Rhamphosaurus, and finally by Professor Marsh to Tylosaurus. A
series of specimens belonging to one individual, from the yellow chalk of
Kansas, consists of several small fragments of jaws with bases of teeth, a
; basi-occipital bone, and five vertebre.

- The basi-occipital is obliquely distorted, from pressure. It has attached
the diverging processes of the basi-sphenoid. The condyle has approximated
3 inches in transverse diameter, and is about 2 inches in depth. The diverg-
ing processes of the basi-sphenoid, at their conjunction with the basi-occipital,
are about 32 inches wide. The vertebre are all more or less crushed and
distorted. One of the specimens, a posterior cervical, has the body below 3
inches in length, and the truncated hypapophysis about 14 inches in diam-
eter. The articular ball and socket approximate 24 inches in diameter.

In three of the vertebral specimens, of about the same length as the pre-
ceding, the hypapophysis is rudimental. The remaining specimen is a more
posterior dorsal, and is of nearly the same size as the other vertebre.

A second series of specimens, belonging to another indiyidual, consists of
several much-mutilated cervical centra, small fragments of jaws with bases
of teeth, a coronoid bone, a fragment of a ee bone, and the end of the
premaxillary.

The latter specimen, represented in Fig. 12, Plate XX XV, exhibits the
peculiar character of the extremity of the muzzle in Mosasaurus and its allies.
It forms a solid, conical, osseous prominence, with the end obtusely rounded
and projecting beyond the anterior teeth. The sides of the premaxillary
toward the end are perforated with large vasculo-neural foramina. The pro-
jecting end of the bone extends about 14 inches in advance of the bases of
the first pair of teeth. Immediately in front of the latter there is a small
conical process. :

Several specimens of a third individual consist of a caudal vertebra and
two teeth, which, from the adherent matrix, have been obtained from white
or cream-colored chalk.

The vertebra is comparatively well preserved, not being crushed nor hav-
‘ing its body distorted, as is so frequently the case in the specimens which
have come under my observation. It is from the caudal series without
diapophyses or transverse processes, and is represented in Figs. 1, 2, Plate
XXXVI. The posterior ball, defined from the body by a narrow ledge, and
the anterior cup are nearly circular, with a slight hexahedral disposition.

276

The neural arch exhibits rudiments of zygapophyses. The bottom of the
body is provided with a pair of deep, conical pits for the attachment of a
chevron-bone. The pits are defined with a prominent margin most project-
ing anteriorly. ,

The measurements of the specimen are as follows :

: Lines
Length of the body inferiorly ...... 2... laces se ees) ec te 20
Diameter of the body at the éxtremities.....-.-.2.. .2.-2--2-5-+..22: eee 30

Of the two specimens of teeth, one is crushed nearly flat; the other, well
preserved, is represented in Fig. 8. It presents the usual form more or less
characteristic of Mosasaurus. It is curved conical, with the inner and outer
surfaces defined by acute ridges. The surfaces are subdivided by longitudinal
ridges, becoming obsolete toward the point of the tooth. The intervals of
the ridges are feebly concave and faintly rugose. Internally near the base
they are delicately striate.

The length of the crown externally is 20 lines; the diameter at base is 10
lines. :

Several additional specimens, apparently belonging to another individual,
consist of small fragments of jaws and palatine bones with bases of teeth.
Among the specimens is a portion of a splenial bone, with its posterior artic-
ular surface nearly entire, as represented in Fig. 13, Plate XXXV. The
articular surface is a pyriform excavation, with a ridge CREE og from the
upper paw internally to near its center.

LESTOSAURUS.
LESTOSAURUS CORYPHAUS.

Dr. Sternberg’s collection of fossils from the Smoky Hill River, of Kansas,
belonging to the Smithsonian Institution, contains numerous specimens of
dorsal vertebree of a mosasauroid, which have the appearance as if they had
pertained to a single individual. There are about fifty of these vertebra,
but all have been more or less compressed from pressure of the superincum-
bent beds to that in which they lay, so that not a single specimen preserves
the exact original term. They differ but little in size, the more anterior
being somewhat shorter than the others.

The specimens appear to belong to the animal described by Professor
Cope under the name of Holcodus corypheus, which Professor Marsh has
referred to another genus with the name of Lestosaurus. .

277

Vig. 5, Plate XXXVI, represents one of the best preserved of the speci-
‘mens from the back of the series. In its present condition the centrum
beneath is 27 lines long, and the ball and socket ends are about 16 lines in
depth and 2 inches in width. The neural arch between the ends of the fore
and aft zygapophyses measures 34 lines.

Another similar specimen, represented i in Fig. 4, exhibits distinct rudiments
of a zygosphenal articulation. The length of its centrum beneath is 33 lines.

The shortest of the series of the dorsals measures beneath about 2 inches
in length; the longest from the back of the series measures about 33 inches
in length.

The same collection contains six specimens of cervical vertebra, which
may perhaps belong to the same species, if not the same individual, as the
dorsals above noticed. The specimeus are all distorted from pressure. One
of them is an axis without the odontoid process and the suturally connected
pieces of the atlas. The articular ball of the centrum is transversely hexa-
gonally oval, 1.2 inches wide, and scarcely 1 inch deep.

Another cervical centrum, in some degree compressed from above down-
ward, is represented in Fig. 6, Plate XXXVI. It measures 1.9 inches in
length below and is 3 inches wide between the ends of the transverse
processes.

Another specimen, represented in Fig. 7, probably a second cervical, is
nearly completé, but considerably distorted. Its measurements are as

follows:

Inches
“je a OH GSE aah Cc d\n ee a 2. 00
Length between fore and back zygapophyses......,.....-----..-------+----- 2. 80
Height from hypapophysis to end of spinous process... ........----..-. .---- 3. 20
Depth of posterior ball of centrum..............-..- ENE PROT ie ee ee oo wap le BO
Width of posterior ball of centrum ....... Be a aa, 8 ate Pwie aie beiad oy a WLEOS

Dr. Sternberg’s collection further contains a number of specimens of
caudal vertebrae, probably belonging to the same species as the former, and
apparently pertaining to two different individuals. There are twenty-six
specimens, all provided with diapophyses or transverse processes, and with
hypapophyses for chevron articulation.

Figs. 8, 9, 10, Plate XXXVI, represent the first and last of a consecutive
series of four anterior caudals. ‘The body of these has the length nearly as
great as the breadth and about equal to the depth. The neural arches are
without zygapophyses, or exhibit mere rudiments of them. The articular

278

ball and socket are wider than high, and are widest below the middle. The
outline of the articular surfaces is emarginate and sloping at the sides above,
and semicircular below. The neural canal is triangular. The transverse pro-
cesses project obliquely from the lower part of the body, and they become
successively narrower. ‘The hypapophyses are excavated into deep conical
pits, directed obliquely’ backward, for movable articulation with chevrons.
The pits are small in the first of the series of specimens and become succes-
sively larger.
Measurements of the two vertebrae represented are as follows:

Tnches. Inches.

Length of centrum, including edge of ball ..... LASS) ble

1, 65 1, 45
Width: of ballet oe eee ee nc. s fe was a ee Se Sette Gee ee: 1. 75 1. 65
Depthtotballes: see .reete een Secs 5 2eoceqs9se 220 75s esa 1. 50 1. 45

In a consecutive series of four posterior caudals with small diapophyses,
the bodies have nearly the same form as in the preceding, but the articular
extremities are of more uniform diameter and of a more hexahedral outline.
The transverse processes are small and project just below the center of the
sides. The chevron-pits are well developed, and resemble those of the pre-
ceding caudal specimens. Two of the caudals are represented in Figs. 11, 12,
Plate XXXVI.

The four caudals together measure 5.3 inches in length. The diameters:
of the cup of the first of the series is 1.4 inches; the diameters of the ball
-of the last of the series is 1.3 inches. ea a

A mutilated posterior caudal centrum, apparently of the same animal as
the preceding, is without diapophyses, hut has well-produced chevron-pits.
The length of the centrum is less than the depth, and this is greater than the
width. The articular ends are hexahedral in outline. The centrum
measures .9 inch in length; 1.2 inches wide, and 1.3 inches deep.

The same collection contains the greater part of a palate-bone, with teeth,
represented in Fig. 12, Plate XXXIV, which may perhaps belong to the
same species as the specimens above described. The specimen contains the
remains of seven teeth, which probably is within two or three of the
complete series. The teeth are compressed conical, strongly curved back-
ward or hooked, obtuse in front, acute-edged behind, are perfectly smooth,

and present no facets or subdivisional planes of the surface.

279

Two limb-bones, represented in Figs 13, 14, Plate XXXVI, pertaining
to the same collection, are supposed also to belong to the same animal as the
above. I feel unable to determine their character. ‘The broader one I sup-
pose to be an ulna ora fibula. It resembles'in its shape and construction
the corresponding bone of the New Mexico mosasauroid, represented in Fig.
10, Plate XX XV, but is much smaller.

Its measurements are as follows:
Inches. Lines.

enehn ait) GE WpPPEL CXELEMUIGY) . 6 ony oso aw men pin we hae pea wis ee ee = 4 3
ibreadin of upper extremity. .2... Ss2.0-2-54 22-022 - eee ee aE rey ee ee 2-9
SEMEIGNESS Of WP PEl CXbLCIMILY - <2 22 asin. osc nse aa acedemse etter eens ess set PLO
Breadth of lower extremity........-........- leaned tai AES aaa is in la yior aS 3 +
Minekunessiot lower extremity ..-. .----.-2-0001-0-0e00- ORE EEE pean Bea Ah
OSS TEP Sieg ti FG Ra 0001S RP 2 0
imeenessios shat at middle... 222.402. 00 etlDa i bee ede aee) 0 1

The smaller bone of Fig. 14 is probably a radius or a tibia.

Its measurements are as follows:
Inches. Lines.

Same RS I sles 2 20a) io Boe Skin las. n's wees chevelle xedleta ovale wale gee FS Dee D aes 3 t
CC AUMMG! UpPPCLr OXtLEMIbY =<... 2-6 eek ese kee e cee ceenee Payee gs 1 44
Mineloness of upper extremity .....-.......4.....-....--- Jest eh ae ew O59
PEMD ROMMONWVED OSOLOMILY - 2 =: 2-2 ce ws We Seales wees cee sees ene eece eens 5 eS 1
manos OF LOWER CXtEMMby 42 Wi ni2 clk oe eka cle ele eee ees uce eee 0 9
Pivot shatt at middle .............-- 2.02.26 6. FOS Se Mee oe 0 9
iineeleme svat shattrat Middle. oo. ue eee woe ee we ene cede cen edna vee (1 Pea gy

MOSASAURUS —— (7?)

The cabinet of Swarthmore College, in the vicinity of Philadelphia, con-
tains a number of fossils from the Cretaceous formation of Nebraska, pre-
sented by Mr. George 8. 'l'ruman. They were collected by him from the
hills on the Missouri River, near the Santee Agency, in L’Eau qui Court
County. They consist of bones and teeth of fishes and reptiles, among
which are a number pertaining to the Polycotylus latipinnis of Professor
Cope, originally described from remains found in Kansas.

An anterior caudal vertebra of a Mosasaurus, in Mr. Truman’s collection,
is represented in Fig. 15, Plate XXXVI. The vertebra has the form usually
assigned to the genus. It retains the neural arch, but has lost its spine.
From the lower part of the body project the roots of strong transverse pro-
cesses. Beneath the body there is a strong pair of eminences projecting just

280

back of the middle and terminating in nearly flat articular facets for a chevron.
The surface between these eminences forms a moderately deep concavity.
The measurements of the specimen are as follows:

Lines
Length ofthe body, beneath --s.- Ape <c eee. ace nie ieee eee eee oe 31
Depth anteriorly <2). i's 2 soca SEO Sic Se an ter see es eee cr 35
Breadth anteriorly .- «2... - 2 ae. a= on mmiala eine ote sala Sas a note = a 42

Mr. Truman’s collection contains several teeth which may probably belong
to the same animal as the vertebra just described.

_The largest of the teeth is represented in Fig. 18, Plate XXXIV. It pre-
sents the usual mosasauroid form, being curved conical, with the inner and
outer surfaces unequal in extent and degree of convexity and separated by
acute ridges becoming more prominent near the apex of the crown. The |
enamel is longitudinally striate, especially toward the base of the crown,
where more marked ridges show a tendency to divide the surfaces into narrow
planes.

The specimen is a shed tooth, and measures a little more than 2 inches in
length ; and the diameter at base is about 14 lines.

A second tooth, represented in Fig. 21, has nearly the same characters
as the former. It is smaller, more compressed, so that its section is
more elliptical, and its inner and outer surfaces are more equal. Tt is also
a shed specimen, and measures 14 inches in length. Its base, an outline of
which is seen in Fig. 22, measures 10 lines fore’and aft, and 8 lines trans-
versely.

The third specimen, represented in Fig. 19, has nearly the same form as
the preceding, but has its surfaces distinctly subdivided into narrow, slightly
depressed, smooth planes, of which there are six externally and seven inter-
nally. Transverse outlines of the base and of the crown a short distance
above are given in Fig. 20. The length of the tooth, also, like the other, a
shed specimen, has been about 20 lines. The diameter of the base fore and
aft is 10# lines; transversely 83 lines.

Fig. 16 represents a small tooth, accompanying the former specimens,
which I suppose to be from the back part of the series of the same spe-
cies as the teeth of Figs. 18 and 21. It is more curved in proportion
with its length than in these, but has nearly the same outline in trans-
verse section, and has the enamel striated in the same manner. Its length
when complete has been about an inch. Its diameter at. base fore and aft

is 6? lines; transversely 6 lines.

281

CLIDASTES.

The extinct reptilian genus Clidastes, characterized by Professor Cope,
is especially distinguished from Mosasaurus and its nearer allies by the
possession of an additional mode of articulation to the ordinary one in
the vertebrae, such as is found in the living iguanas. The vertebre are
otherwise nearly like those of Mosasaurus. The general form and construc-
tion of the skull and the character of the dentition are the same in both
_ genera. .

Half a dozen species of Clidastes have been indicated by Professors Cope
and Marsh, from remains found in the Cretaceous formations of New Jersey,
Alabama, and Kansas. |

CLIDASTES INTERMEDIUS.

A species different from those described by the authors just named is
indicated by a small collection of remains, presented to the writer by Dr. J.
C. Nott, formerly of Mobile. The specimens, consisting of several jaw-frag-
ments and vertebra, were taken from an excavation 40 feet beneath the
surface, imbedded in the rotten limestone, of Cretaceous age, in Pickens
County, Alabama. ‘

The remains indicate a species of more robust proportions than Clidastes
propython, described by Professor Cope, from the great part of a skeleton
discovered in the same formation near Uniontown, Alabama. It was a third
less in size than the typical species C. zgwanavus, described by the same
author, from an isolated dorsal vertebra obtained from the Cretaceous green
sand of New Jersey.

Fig. 1, Plate XX XIV, represents the anterior extremity of a dentary bone,
probably more than: one-half of the whole. It would appear to have been
proportionately of greater depth and thickness in relation with its length than
in C. propython. It is also of more uniform depth at its fore part and less
pointed at the end.

The fragment contains the remains of a series of nine teeth, occupying a
space of 54 inches. The teeth surmount robust osseous pedestals, of which
about two-thirds of the length are included within about an equal extent of
the depth of the jaw.

The crown of a second tooth, (Fig. 5,) inclosed within a cavity of the

pedestal of its predecessor, is 5 lines in length and about 24 lines in breadth
36 G

282

at base. It is curved conical, feebly compressed from without inwardly, and
has its inner and outer surfaces well defined by acute borders. The exposed
inner surface of the crown exhibits no divisional planes, and has its enamel
minutely wrinkled. 2

The crown of a tooth (Fig. 4) occupying a corresponding cavity of the
ninth pedestal, probably not fully produced in its length, in its present condi-
tion has a breadth exceeding the latter. The crown is a broad cone about
the length of the tooth first described, but with double the width at base.
The exposed inner surface is defined in the usual manner from the outer, and
exhibits no divisional planes. ‘The enamel is minutely wrinkled.

The depth of the jaw-fragment below the visible base externally of the
first dental pedestal is three-fourths of an inch; the depth below the seventh
pedestal is 144 lines.

The splenial bone advanced as far as the back part of the sixth tooth:
Beyond it the Meckelian groove is deep and wide compared with that in C.
propython, and extends to near the end of the jaw.

Fig. 2 represents a posterior fragment of the opposite dentary bone, con-
taining the remains of a series of six teeth. The mutilated crowns of the.
anterior two teeth retained in the specimen exhibit a swollen base, which
may also be seen to be the case in the crowns of the sixth and seventh teeth
of the anterior dentary fragment.

From the two fragments of opposite dentary bones I am unable to ascer-
tain the number of teeth which belonged to the complete series, but it seems
to me that the seventh tooth of the anterior fragment about corresponds with
the first retained tooth of the posterior fragment, which would indicate a
series of twelve teeth.

Fig. 10 represents an axis from the same individual as the preceding speci-
mens. It has the same form as that of C. propython. 'The odontoid process,
and the elements of the atlas, all of which articulate suturally with the axis,
are detached from the specimen and do not accompany it.

The measurements of the axis are as follows:

Lines
Length of body through center, devoid of odontoid process..........-..--. aye eS
Breadth of axis between posterior ends of diapophyses..:.-.--..... -.-.------ 28
Wiidthsot posterior ball =< 22.2. secrecy ls te aes
Heichtioi posterior ball 2.032. -o en ee ieee nsuist Sees See 10
Width of hypopophysis...... --..~.- We ie So Bet LSS a eee 8

Two mutilated dorsal vertebrae exhibit the zygosphenes and zygantra as

283

well deyeloped proportionately as in Clidastes propython. Measurements of
the better preserved of the specimens are as follows :

Lines
Meo UMPOtihe DOWY MfeLiOLly. 2.42 5 om aunt Seta appraise apt 22a Gee a eee arene is)
Pimuesttne ball and socket 22.5, nia. > oct Segre oie e> dd ee eee gat et id
Height of the ball and socket .-.....-.-. Jone sete se sna 2 S55 oe dSnek see 10

CLIDASTES AFFINIS.

Some remains submitted to my examination by the Smithsonian Institution
may perhaps indicate a species of Clidastes distinct from the former. The
specimens were discovered by Dr. George M. Sternberg, United States Army,
in the Cretaceous formation on the Smoky-Hill River, Kansas.

Fig. 6, Plate XXXIV, represents a nearly complete dentary bone, which
is accompanied by that of the opposite side. It contains the remains of a
_series of twelve teeth, while there is one less in the other bone.

The anterior extremity of the jaw is of rather less depth and slightly

greater thickness than in the corresponding part of Clidastes intermedius.
The splenial bone appears to have reached as far forward as the position of
the fourth tooth.
The anterior teeth appear to have been larger, and the intermediate ones
smaller, than in C. intermedius, though this may have been a variable char-
acter in the same species. Portions of the bases of the crowns of several of
the back teeth exhibit the enamel strongly striated, and the surfaces of the
teeth also present evidences of subdivision into narrow planes.

A fragment from the back part of a maxillary from. the same individual
contains the bases of four teeth. The last of the series retains part of the
crown, which is strongly striated internally, and distinctly subdivided into
narrow planes externally. In the remains of the teeth of the specimens
referred to C. intermedius there is no trace of subdivisional planes to the
crowns, but this may have been a variable character in the species.

Fig. 7 represents the back part of the right ramus of the mandible of the
same individual, seen on its inner side. It exhibits the same construction as
the corresponding part in C. propython. The articulation is nearly equalfy
divided between the angular and articular bones.

Measurements of the jaw-specimens are as follows :

Lines
/ MDE UID CY CE DEPT NOT SRR eee a ane ee ney ee era ee te 126
Length of series of twelve teeth...........- : RS ee oO et Oa a Be 13al

Depth of jaw below first tooth .-.-........... ee eee te oe eo oe 10

Lines
Depth of jaw below fourth tovth,..-s--72-s. ae See bef ek oon See 1%
Depth of jaw at the outer side of the glenoid articulation... ... - ee aR Pei:
Length of projection back of the glenoid articulation ..................-..-.... 20
Transverse diameter of glenoid articulation ...:.............0.0:-2--ee-cnceee 18
Vertical diameter of glenoid articulation -..--2-.- -.222 22022 seecee seen ee 16

An axis and a dorsal vertebra accompanying the former specimens probably
pertained to the same individual. They are both considerably distorted from
pressure at the sides.

The axis is rather longer than that of C. intermedius, while its hy popophysis
is considerably smaller at the extremity, and the ball of the centrum is more
uniform in diameter, or is less emarginate above. The lower element of the
atlas remains in firm sutural connection with the body of the axis, but the
odontoid element of the latter and the lateral elements of the atlas are absent.

The dorsal specimen retains the neural arch with its characteristic zygan-
tral articulation. .

Measurements of the vertebre are as follows:

Lines
Length of axis through center of the body. ......-.........-..--...- yt (eee 22
Width of ball otibodyiof axtsr. se 2see oe ae ee eee oe ee pte ee 103
Height of ball of body ofjaxis: --<2- .-2- 5-25 ea2-e-ene = 222-2 er
Length’ of body of dorsal vertebra.inferiorly ..-.:-.2:.2422. 22.4.2... oe 22

Accompanying the former specimens there are several others which, if
they did not pertain to the same individual, probably belonged to the same
species. .

Two fragments of the upper part of the cranium represented in Fig. 8
resemble the corresponding portions in Ciidustes propython, as described and
figured by Professor Cope, and differ only in the greater size. Fig. 9 repre-
sents an isolated basi-sphenoid bone, probably from the same skull.

These skull-fragments indicate an animal about one-third larger’ than C.
propython, as described by Professor Cope.

It is a question of some importance how far difference in size among the
mosasauroids may be a test of difference in species. Among the numerous
remains of these animals which have been discovered I have never yet
observed any which presented any evidence relating to age. In no case
have I seen a.vertebra in which the neural arch was not continuous with the
centrum, so that I have been led to suspect that the former grew out of the
latter, as in most fishes, and was never united with it by articulation, as in
the crocodiles, &c. In this view of the case, some of the many described

285

species of mosasauroids may have been founded on different ages of the
same. d

Fig. 11 represents a humerus accompanying the former specimens, and
probably belonging to the same species, if not the same individual. In its
form and construction it closely resembles the corresponding bone of C. pro-
’ python.

The specimen is somewhat crushed, which perhaps to some extent makes
it appear proportionately flatter than the humerus of C. propython, described
and figured by Professor Cope.

The length of the bone does not exceed aie breadth of its distal extremity,
which is the wider one.

The measurements of the specimen are as follows :

; Lines
ot MOMmUUNMeLIS Ab MNLOGe i. 2.. on sc2 eens scene denn ee ker eset rece aeeeeusee 30
ipreqduver proximal extremity........-..-+-1-.-00+--- Uy AES hare cal sre olat ie Sew) A at 28
eeremnr on UistalhOXGOMIGY <<. <2 jc <j.64 snide eee ene nee rele wes awccnceeeeres oR sie 35
Breadth at constricted middle of shaft...... 2.0.22... .--. 66sec eee eee ee eee 20
Sabre eet OMIM ts cteyete) </aisgie whale alah vais «cise c = Sc een 22s ages sees cacdeneswes 84
Cau PULETEV SS) (Cig WIS) 121] Bey 01 (ee ed oe 94

Order Lacertilia. (?)
TYLOSTEUS.

TYLOSTEUS ORNATUS.

The above name has been proposed for a supposed genus of lacertian
reptiles, founded on a singular fossil represented in Fig. 14, Plate XIX.
The specimen was obtained by Professor Hayden in the “Black Foot”
country, at the head of the Missouri River, and was probably derived from
the Cretaceous formation. It looks asif it might be an element of the
osseous dermal armor of some animal, whether reptile or mammal is by no
means certain, though, as before intimated, I suspect the former.

‘The specimen is imperfect or broken at the borders. Its inner surface is
concave; the outer convex, and ornamented with large mammillary bosses.
The latter are about fifteen in number and of different sizes. They are
porous and of a less dense character than their shield-like basis. The
diameter of the fossil is about 2 inches; its thickness an inch.

Accompanying the specimen just described there is an isolated phalanx,
represented in Fig. 13. Though suspected to pertain to the same animal,
the reference is uncertain. It is a terminal phalanx nearly 2 inches long,

286

and with the expanded extremity nearly circular at the border and 16 lines
wide. ‘The upper part of the bone presents a nearly straight slope in its
length, and is convex transversely. The under part is likewise straight along
the middle, transversely convex posteriorly, and nearly flat at the expanded
end. The lower surface of the latter presents near the middle a pair of
vascular foramina, and several similar foramina are found near the border.’
The articular end is transversely elliptical and barely depressed. Its trans-
verse diameter is 15 lines; its vertical diameter 10% lines.

Order Sauropterygia.

OLIGOSIMUS.
OLIGOSIMUS GRANDZVUS.

A fossil obtained on Henry’s Fork of Green River, Wyoming, during
Professor Hayden’s exploration of 1870, would appear to indicate an extinct
reptile allied to Plesiosaurus and Discosaurus. In general aspect, the
specimen is different from those in company with it, and I think it doubtful
whether it was an associate of the other fossils, which belong to the Bridger
Tertiary formation. It was found as a detached specimen, and has no
adherent matrix. It probably is of Cretaceous age.

The fossil, represented of natural size in Figs. 18, 19, Plate XVI, consists
of the body of a caudal vertebra, apparently from the root of the tail. It
was evidently from a mature animal, as the neural arch was firmly co-ossified,
leaving no trace of the original separation. |

In shape and construction the body resembles the corresponding portion
of the vertebre in Plesiosaurus and Discosaurus, but the proportion of length
to the other dimensions is much less, and the depth also is not so great.

The body is biconcave, the concavities being of moderate and nearly equal
depth. Deepest at the central half of the area, the peripheral half of the
articular surfaces becomes more abruptly shallower, and with the deflexed
edges somewhat convex. Near the border, the articular surfaces are defined
by a narrow circular groove.

The posterior articular surface of the body at the sides below is deflected
in a pair of widely separated facets for a chevron-bone. The facets are
sustained on processes extending forward more than a third of the length of
the body. Similar facets and processes are absent on the front of the bone.

287

The sides of the body are comparatively feebly constricted, much less than
in Plesiosaurus, and beneath, the constriction is trifling in degree.

Transverse processes or diapophyses project from the sides of the body,
just above its middle and below the conjunction of the neural arch. Their
bases are broadly conical; wider than high, and appear originally to have had
a sutural connection. The ends are broken off in the specimen.

~The usual nutritive foramina are visible at the floor of the vertebral canal
and beneath the body.

The peculiarities of the fossil appear to justify its reference to a previously
undescribed genus and species, and we have therefore attributed it to an
animal with the name at the head of this chapter.

The measurements of the specimen are as follows:

Lines

_ Length of body beneath .............. latch Saeco diye: BS eee ee aoe 02
PROMO MNONy WRTOMD: = 2). 62 sjacecs eds ca eee ood eews 20 LA ee er PtSi: Bae hea n 19

' Width of body in front ...... Re Mine fac) WS ie Bee & OLR En Ta APSE tere OMeRe RC ae mem. een 23
SM nO DOU abi CHEVFON-TACCLS 0-6-7. ons = as ae enne cance Sele deen ceenwease 18
Peieumbotavertenral Canal). 2210. .5 2 fc eee ns eee deh ak ee ene ete cece eed eae 6
SiPE IMGT RESTOL NEVO) ahh. te ogee 54s. sk ben tae act ths cee teteseviebh awe dobre 8

NOTHOSAURUS.
NoTHOSAURUS OCCIDUUS.

The above name was appropriated to a saurian indicated by a detached
vertebral body or centrum, represented in Figs. 11 to 13, Plate XV. The
specimen was obtained by Professor Hayden.on the Moreau River, a tribu-
tary of the Upper Missouri, and is probably a Cretaceous fossil. In form and
construction it resembles the vertebral centra of Nothosaurus, an extinct
reptile of the Triassic formation of Europe, and probably it belongs to an
‘animal of the same order if not the same genus. The specimen appears to
pertain to a dorsal vertebra, to which the neural arch was attached by broad
suture, as usual in the sauropterygians.

The body is nearly cylindric, longer than wide or high, and is moderately
narrowed a short distance from the ends. Inferiorly it presents a central
roughness, probably for: ligamentous attachment. The articular ends are
nearly round, but flattened above, and are nearly as wide as high. They are
slightly concave and exhibit a slight central protuberance, apparently the
ossified notochord.

The sutures for the neural arch extend nearly three-fourths the length

288

of the centrum from its posterior end, and they reach downward to the
middle of the sides. The bottom of -the spinal canal is narrowest at the
middle, grooved on each side, and widens toward the ends of the centrum.

The measurements of the specimen are as follows: Length of centrum,
1 inch; depth in front, 104 lines; width, 10 lines.

FISHES.
TELEOSTEI.
Order Acanthopteri.
SPHYRENIDA.

CLADOCYCLUS.
CLADOCYCLUS OCCIDENTALIS.

The genus of fishes above named was proposed by Agassiz on some remains
consisting of large scales and portions of a vertebral column found in the chalk
of Lewes, England. The name was applied on account of the branching of
the tube in the scales of the lateral line; and the fish was referred to the
sphyrenoids. (Poissons Fossiles, V, 103; Atlas V, Tab. 25a, Figs. 5, 6.)

Some large scales, found by Dr. John E. Evans, and subsequently by Pro-
fessor Hayden and Mr. Meek, in ash-colored shales of the Cretaceous-series
of Nebraska, I have supposed to belong to the same or a nearly allied genus.
The scales vary in form and size, and may probably belong to several species.
Mostly they are oval, with the-length but little more than half the depth,
while others are circular, and these may really pertain to a different species,
if not genus, from the former.

A broad oval scale, somewhat distorted and broken at the edges, is repre-
sented in Fig. 5, Plate XXX. The inner portion exhibits numerous radi-
ating ridges, while the outer portion, separated from the former by a narrow
smooth tract, presents a minutely tubercular or granular aspect. The depth
of this scale is estimated to have been nearly 25 inches, and its length nearly
14 inches.

Another similar but less perfect specimen appears to have measured about
13 inches wide by 14 inches long.

A third specimen, represented in Fig. 21, Plate XVII, has measured rather
more than 1 inch wide and # inch in length.

Another scale, represented in Fig. 22, has the same structure as the pre-

289 —

ceding, but is circular in form. Its diameter is about 14 lines. This prob-
ably belongs to a different species, and perhaps genus, from the former.

Another specimen is a nearly smooth oval scale, which has been about 13
lines wide and 9 lines long. It exhibits obscure radiant limes on the inner
portion, but no granulations are evident on the outer portion. This may
belong to another fish than that of the preceding specimens.

ENCHODUS.

Encuopus SHUMARDI.

- The extinct genus above named was inferred by Agassiz from some remains,
consisting of jaws and teeth, found in the chalk of Europe, and was by him
attributed to the sphyrenoid family. Several species have been since de-
scribed from similar remains found in the deposits of Cretaceous age in the
United States. One of these, under the above specific name, was indicated
by a dentary bone with teeth, found by Dr. Benjamin F. Shumard in the same
formation in which were discovered the large scales referred to Cladocyclus.

The specimen is rudely represented in a reversed position in Fig. 20, Plate
XVII. The dentary margin of the bone is 11 lines long, and contains six long
narrow teeth, and in the back intervals a number of minute ones.

The first of the larger teeth is the longest, and is situated a short distance
from the end of the bone. Including its thickened base it is 2 lines long by
about one-fifth ofa line wide. It is a long, narrow, straight cone, laterally com-
pressed, trenchant at the borders, and ends in a point with a slight posterior
projection or half barb. The posterior five larger teeth are situated at irreg-
ular distances apart, and measure from one to one and one-fifth lines in
length by about one-sixth of a line in breadth at base. They are nearly like
the largest tooth, but are slightly more curved, and have no projection to the
back of the point. The minute teeth in the back intervals of the larger ones
and back of these are not over the one-fifth of a line long.

PHASGANODUS.
PHASGANODUS DIRUS.

An extinct genus of fishes supposed to belong to the sphyrzenoid family,
and nearly related with Enchodus, has been described under the above name.
It was inferred from a specimen of a mutilated dentary bone with teeth,

37 G

290

imbedded in a piece of brown sandstone, obtained by Professor Hayden from
a Cretaceous deposit he has indicated as No. 5, on Cannon Ball River.

The specimen with the remains of five large teeth, reduced one-third, is
represented in Fig. 24, Plate XVII. The third tooth of the series, preserved
entire and separated from the former, is represented in Fig. 23.

The dentary bone exhibits nothing peculiar in the present condition of the
fossil, and appears* not to have differed in any important point from that of
Enchodus.

The teeth differ from those of the latter.. They are proportionately shorter,
saber-like, and situated on broad bases, with an oblique direction to the edge
of the jaw. The thick back border is directed inwardly; the trenchant
border forward and outward. The point is cut off in a slanting manner pos
teriorly. The back part of the crown toward the base and extending on the
sides is fluted, but toward the point and trenchant border is smooth. In sec-

tion the crown is ovate, with the long diameter 2? lines. The length of the -

tooth, including its thickened base, is 10 lines; without the base, the crown

measures 7 lines.
Order Malacopteri.
SILURIDE. (?)
XIPHACTINUS.

"“XIPHACTINUS AUDAX.

Under the above name, I described an ichthyodorulite belonging to the ©

collection of the.Smithsonian Institution. The specimen was obtained from
the Cretacous formation of Kansas, by Dr. George M. Sternberg, United States
Army. I supposed it to be the pectoral spine of a large siluroid fish, but
according to Professor Cope, who has had the opportunity of examining many
remains of fishes from the Cretaceous formation of Kansas, it belongs to a
fish of a peculiar family. This he names Saurodontide, represented by Sau-
rocephalus and some other genera. At first the spine was referred-to the
last-named genus, but latterly he appears to be in doubt whether it belongs
to this or some other nearly allied genus. The specimen is represented in
Figs. 9, 10, Plate XVII, one-third the diameter of nature.

The spine is unsymmetrical, thus rendering it probable that it belonged to
one of the lateral pairs of fins rather than to any of the vertical fins. It is

a broad saber-shaped weapon, in its present condition about 16 inches in

7

291

length, which is nearly its entire extent, judging from the thinning and round-
ing of the broken end. Its breadth the greater part of the length is nearly
uniform, and at the middle is nearly 2 inches. Toward the distal end it
becomes slightly less wide and thinner; toward the proximal end it undergoes
a greater reduction in width, and becomes much thicker.

The upper surface of the spine, represented in Fig. 10, for the most part
is nearly flat except toward the rounded borders. It is invested with a
thin layer of ossific substance of @ more dense character than the compact
bone beneath. The surface is striated or ornamented with raised lines, which
are longitudinal and parallel, but on portions of the surface are somewhat
uregular. Some of the lines branch, and the slightly divergent branches
‘include other commencing lines. At the distal end of the spine, near the
anterior border, the lines break up into finer branches which curve outwardly

to the edge.

The under surface of the spine (Fig. 9) is uneven. A prominent ridge,
commencing at its proximal extremity and occupying more than two-thirds
its width, extends outwardly and gradually declines to a point near the center
of the inferior surface. A shallow groove commences in front of the ridge,
widens outwardly, and extends beyond the former upon the anterior half of
the inferior surface of the spine. Back of the commencement of the ridge
there is a concave hollow, which narrows outwardly into a deep groove, and
this, pursuing the same course, widens and opens downward upon the posterior
half of the inferior surface of the spine.to its distal end.

The posterior groove for nearly half its length proximally exhibits a row
of irregular pits at the bottom. The upper boundary of the groove in advance
of the pits is transversely striate, and beyond the position of the pits exter-
nally the corresponding surface presents the striz curling outward to the
back edge of the spine. The bottom of the groove, external to the position
of the pits, continues as a shallow channel running along the middle of the
‘spine inferiorly to its distal end.

The anterior border of the spine is convex in the length, obtuse internally,

*and acute externally. The posterior border is concave longitudinally, obtuse
internally, and less acute externally than the anterior border.

The inner extremity of the spine appears bent upward into a hook-like
“eminence with a pyramidal base extending above the general level of the
spine. The end of the hook-like process is broken off. Its inner surface

292

forms an ellipsoidal longitudinal convexity, with the lower half more
prominent and appearing to be an articular eminence. The outer extremity
of the spine is broken, but it appears to have been rounded transversely,
though it may have been pointed.

The measurements of the spine are as follows:

Inches

Length of the spine in its present condition ........-......-.. ,-.- «..ssenuee 16
: Lines
Breadth of the spine beyond the articular hook.................-...-----.----- 17
iBreaduhy at phe imnerachind sees eee eee eee eee evs tess cs eee 21
Breadth ‘at the middles as. 2-156) 22) ae See Se octal op ot iaend a)! ae ol ole ee er 23
‘Breaduhimear tier aistalvendiae ser eee ae ari are eels. odie cee eee 20
Thickness of the spine beyond the articular hook ...-.. ......--....-...---..- 14

Thicknessiat the:inner third: j2 + s2-s22 62 teds aoe cee oe es ie eek eee / 94
Thickness at the middle ....-...-..- sd 12 (a vhayete fe taifeta seyota) siete mea 6
Thickness near: the :distal.end!:.4.::5..-. 5.0554 See bas sean ee SEE 3

The transverse section of the spine near the middle forms an irregular
ellipse, as represented in the accompanying
figure. The left-hand side beneath represents
the posterior groove opening downward.

Since writing the above, I have had the op-
portunity of examining the proximal half of a similar spine, from L’Kau
qui Court County, Nebraska. It was found in association with remains of
Mosasaurus, &c., by George S. Truman, and presented by him to Swarth-

more College, Pennsylvania.
GANOIDEL
PYCNODUS.

This genus, typical of an extinct family of fishes, -was originaily indicated
by Agassiz in the Poissons Fossiles. Many species have been described,
mainly from teeth and fragments of jaws with teeth, which are comparatively
large and stout, and were adapted to crushing hard food, such as mollusks
with their shells, crustaceans, &c. The remains have been found in the Tri-
assic, Jurassic, Cretaceous, and early Tertiary formations of Europe.

PYCNODUS FABA. .

A specimen, represented in Fig. 16, Plate XIX, indicates a species to
which the above name has been given. It was submitted to my examination.
by Dr. Wilham Spillman, who obtained it from the Cretaceous formation near

Columbus, Mississippi.

293

The specimen consists of a fragment of the ramus of a lower jaw con-
taining a number of teeth. Four principal teeth and part of the attachment
of another are retained in the fragment. These teeth are ranged obliquely
parallel with one another from within backward and outward. In outline
they are elongated-bean shaped, being slightly concave in front and convex
behind, and slightly wider externally than internally. The first of the series
is 74 lines wide by 2% lines fore and aft, and they successively increase in
breadth to the last, which measures 8? lines wide by 2% lines fore and aft.

At the bottom of the slope, to the inner side of the large teeth, there is a
row of three smaller teeth and the traces of attachment of a fourth one.
The three teeth, like the others, successively increase in size from before
backward. ‘They are ovoid, and situated obliquely nearly opposite the inter-
vals of the large teeth. The first of the series is 24 lines in diameter fore
and aft and 14 lines transversely; the last one is 34 lines by 2 lines.

The jaw-bone internal to the teeth just described rises in a ridge toward
the symphysis. The slope at the fore part of the ridge exhibits the attach-
ments of two minute teeth, indicating a second row internal to the largest
teeth.

To the outer side of the latter the specimen retains evidences of two rows
of smaller teeth. Of these, the first row shows remains of seven teeth in
the length of space occupied by the five principal teeth, and, like these, they
successively increased in size. Only the fourth tooth of the row is preserved,
and this is transversely ovoid, with the long diameter 2 lines wide and the
short diameter 1? lines.

Fig. 15, of the same plate, represents a specimen apparently from the same
species, belonging to the Museum of the Academy of Natural Sciences of
Philadelphia. It was presented by Dr. J. H. Slack, who obtained it from the
green sand marl of Crosswicks, Burlington County, New Jersey. It consists
of a small jaw-fragment containing three broad teeth similar to the largest
ones above described.

An isolated tooth from New Jersey, submitted to my inspection by
Professor G. H. Cook, is noticed in the Proceedings of the Academy of
' Natural Sciences of Philadelphia for 1857, p. 168, under the name of
Pycnodus robustus. The specimen represented in Figs. 18, 19, Plate
XXXVII, has the same shape as in the largest teeth of those referred to
P. faba, but is much larger. Its long ‘diameter is 144 lines, and its short

diameter nearly 4 lines.

294

A similar tooth, nearly the same size but slightly more sigmoid, is repre-
sented in Fig. 96, page 244, of Professor Emmons’s Report of the North
Carolina Geological Survey, published in 1858. The specimen is «attributed
to the Miocene Tertiary, ‘and is referred to a species with the name of
Pycnodus carolinensis.

HADRODUS.
Hapropus PRISCUS.

The genus above named is obscure in its relations, and was originally
described in 1857, in the Proceedings of the Academy of Natural Sciences
of Philadelphia, It was founded on a specimen consisting of a bone with
two singular-looking teeth, discovered by Dr. William Spillman, in the Cre-
taceous formation in the vicinity of Columbus, Mississippi.

The specimen represented in Figs. 17 to 20, Plate XIX, I have supposed
to be a premaxillary bone of an animal allied to the extinct genus Placodus,
formerly considered to be a pycnodont fish, but now determined to be a
sauropterygian reptile.

The bone is unsymmetrical, and supports two strongly co-ossified teeth.
Whether the specimen is complete in itself or whether it is part of a larger
bone, I have not been able to ascertain.

The bone is quadrate in outline; thicker and longer on one side, and
oblique at the upper border. The anterior surface is convex and compara-
tively smooth. On each side and extending posteriorly, the bone is deeply
excavated into large reserve cavities for successional teeth. The back surface
between the cavities inclines from each side, forming a median angular gicove
descending to the interval of the teeth. The bone is more porous and striated
posteriorly than anteriorly.

The teeth remind one of the premolars of some pachyderm, rather than
the teeth of a fish or reptile. They are not exactly alike, and are co-ossified
with the bone by a firm osseous base or root, striated in front. They are
quadrate in outline, with the breadth and height nearly the same, and the
thickness about half. The crown is convex in front and at the-sides, and is
bilobed at the triturating border, which slopes off posteriorly. An acute.
ridge and the conical blunted summits of the lobes define the outer from the
inner surface. Smooth enameloid substance invests the crown, extending
twice the depth on the outer surface that it does on the inner surface. In

transverse section the teeth are ovoid. °

295

The measurements of the fossil are as follows:

: Lines
Dee OL WON xo wk Ae eee ee cela ae eR ane el 18-20
eth a CAUNeR ONCE 2). - fase ucts ee ee ese cise vent ease) | peat s es cee ae cle 1G
Meratmeominenarcer OO so jou ava fell inte |Jas hee ee eeeeS oye dere:
PMO RPSAIMC co cic 20). Su Sosa d oa sted oo/ames gaeds ish SAO ase Ns el IP le 8
NMI RMESS' OL SAMO--. 5602552 e eee wee ete Se Seen rear SO ee ele as 53
Me SpeMOMMONAMOM. Ye02 5/521. Joh) hi an es id ae SiS Sees tye ee aiid its Rbmee 63
SEIT, OSE MeT TOL) MAE BA NP ne ee Sein Sle aero re ei eee ae anne oe ee ae 12
MMUMEOM SATO: coe caren cision oa a ek eee ele ety ate sc ey Sa, Seep alee oa 3.0 aio. Was
aEMIMeSS OF, SAME -- 4-5-0 2 o--- oe se tee oe- eae eon Be beSh = Sa 2 EE 44
Dig OW Glial Jos ARE Pe) cae te eee oe ar eee nee 64

I have arranged Hadrodus with the Pycnodonts, though, like Placodus, the
discovery of additional material may prove it to be a sauropterygian reptile.
Of Placodus, Professor Owen remarks that the ‘teeth are implanted by
short simple bases in distinct hollow sockets,” (Paleontology, 218;) and Meyer
says, “In wircklichen Alveolen stecken eigentlichen nur die Schneideziihne
mit gut ausgebildeten Wurzeln, der Wurzeltheil der iibrigen Ziihne ist mehr
mit dem Knochen, dem die Zihne angehoren, verbunden.” Hadrodus in
the relation of the teeth would appear to be different, as they are firmly
co-ossified by short bases with the border of the jaw. They exhibit no
trace of implantation by sockets, though the successional teeth before being
established in a fixed manner in functional position must appear at least to
spring from sockets.

ELASMOBRANCHIL.
Order Plagiostomt.
PTYCHODUS.
Prycuopus Morroni.

The extinct genus of cestraciont fishes above named was inferred by
Agassiz, from isolated teeth, the only parts yet found which can be with any
certainty referred to the same animal. A number of species have been indi-

cated, mostly by the same authority, from specimens found in the Cretaceous
formations of Europe and America.

Teeth of Ptychodus Mortoni have been Accorerea in the Cretaceous de-
posits of Alabama, Mississippi, and Kansas, but I have seen none from the
corresponding formation of New Jersey or elsewhere. 7

The Smithsonian Institution has submitted to my examination a collection

296

of fourteen specimens of teeth obtained by Dr. George M. Sternberg, United
States Army, from the banks of Chalk Bluff Creek, a branch of Smoky Hill
River, about sixty miles east of Fort Wallace, Kansas. The specimens were
found in two parcels, each together, as if pertaining to two individuals.

The two largest teeth, of which one is represented in Figs. 1, 2, Plate
XVIII, are probably from a median position in the mouth or jaws. They
are symmetrical in form, and in outline are transversely quadrate oblong with
rounded angles.

The crown is prominently convex, with the front and lateral borders nearly
straight, the back border slightly concave, and the angles rounded. Poste-
riorly it is impressed with a moderately concave crescentoid sinus. The
summit is crossed by a short transverse ridge, from which numerous ridges
radiate. Descending on the sides of the crown the ridges branch, and about
half way down terminate in a fine reticulation which extends to the borders
of the tooth. The root is a quadrate plate with the same outline of form as
the border of the crown. :

Three other specimens of the same parcel as the preceding appear to
have been lateral teeth in relation to them in position in the mouth. They
are nearly alike in shape and size; one of them being represented in Figs.
3, 4. They are not symmetrical as in the larger teeth, and their outline
is more reniform. They are proportionately narrower at one side, and wider
and more extended on a base beyond the conical elevation of the crown at
- the other side. The sinus is of less height, and the ridges of the crown
are more convergent at the apex of the cone. The root appears to recede
from the narrower side and reaches nearly to the edge of the crown on the
opposite side. The remaining two teeth of the same parcel have the same
character as those just described, but are considerably smaller.

Measurements of some of the specimens are as follows:

Figs. 1, 2. Figs. 3, 4. |"
Lines. LDines.« Lines. Trines. Lines.
IB TEAC LMECLANS VeTSElyae eee mene aee 22 20 184 17 13
Breadth antero-posteriorly . ......-..-. 124 124 “729 9 1s
Height from bottom of root .....-.....-- 124 12 8 9 1S

Of the two largest teeth, of the second parcel, which are nearly alike, one
is represented in Figs.5 and 6. They are intermediate in character to those

297

previously described, being less symmetrical than the large teeth and more
so than the smaller ones, and their crown is proportionately more prominent
than in any of them. Of three teeth smaller than the former and succes-
sively diminishing, that of intermediate size is represented in Figs. 7 and 8.
They have the same form as the unsymmetrical -ones of the first parcel, but
have their crown proportionately much more prominent.

The remaining two teeth are different in shape from the former. The
larger one has the crown proportionately less prominent, with the central
conical elevation less strongly radiate. The iner side of the base forms an
obtuse angle, and is strongly impressed toward the back border. The front
border of the base of the crown is short, nearly straight, and forms with the
_ oblique outer border an obtuse angle.

The smaller tooth is represented in Figs. 9 and 10, and has nearly the same
shape as the former, but the crown appears comparatively flat with a central
nipple-like eminence, and the anterior and outer borders are more continuous.

The measurements of the teeth are as follows:

Figs. Figs. Figs.
5, 6. Gre: el:

Lines. | Lines. | Lines. | Lines. | Lines. | Lines. | Lines.

Breadth of crown transversely . .--.-- 144) 14 113 83 7 LO aE
Breadth of crown antero-posteriorly .. 7 8 6 5 + 6 44

Height of crown from bottom of root..| 104 94 8 6 4 5$ 35

.

Several specimens of teeth of Ptychodus Mortoni have heen submitted to
my inspection by Dr. William Spillman, who obtained them from the Creta-
ceous formation near Columbus, Mississippi. One of the teeth, of large size,
and considerably worn at the summit of the crown, is represented in Figs.
11 and 12. It is symmetrical in shape, but has a more reniform outline than
the large teeth from Kansas. The anterior and lateral borders of the crown
nearly form a semicircle, and the posterior border is deeply emarginate.
The sinus is deeper than- in the Kansas specimens, but the arrangement of
the striations of the crown appear to be the same.

Two other specimens, about half the size of the preceding, have nearly the
“same shape, but have their crown proportionately more convex at the fore
. part of the base. :

38 G

298

The measurements of the Mississippi specimens are as follows.

Figs. 11, 12.

Lines. Lines. Lines.
Breadth of crown transversely ..-.--...--.-. eats w ene 20 12 103
Breadth of crown fore and ait--=-5 2 a2 -emceane 10 63 7
Heieht-of crown”... 12-63. 022 aoe os ce te ee 3) oie eee ae Oo if

° *To worn summit.

The Museum of the Academy of Natural Sciences of Philadelphia contains
nine specimens of teeth of Ptychodus Mortoni from the Cretaceous formation
of Alabama. These in genera: resemble the symmetrical and unsymmetrical
‘teeth above described. One of the specimens from Green County, Alabama,
is represented in Figs. 13, 14. Its sinus is more sharply triangular than in
the previous specimens.

Another tooth, approaching in size the largest Kansas specimens, has a
more distinct conical ridge on the summit of the crown from which the other
ridges radiate. A third tooth nearly resembles the Kansas specimen repre-
sented in Figs. 8, 4, and has the summit of the crown worn away, as in the

large Mississippi specimen, represented in Figs. 11, 12.

Measurements of Alabama specimens of teeth are as follows: “iy
Figs. 13, 14.
Lines. Lines. Lines. Tines. Lines.
Breadth of crown transversely....-.--. 16 144 16 13 9.
Breadth of crown fore and aft ........ 105 84 9 7 5s
Height of crown from bottom of root..| 103 Or eee 8 64

PrycHODUS OCCIDENTALIS.

A peculiar species, to which the above name has been given, is indicated
by specimens of teeth discovered by Dr. John L. Leconte in an ash-colored
chalk of the Cretaceous formation a few miles east of Fort Hays, Kansas.

The most characteristic, and at the same time the largest specimen, is
represented in Figs. 7, 8, Plate XVII, of the natural size.

The shape of the tooth and the arrangement of the ridges of the crown
are quite different from what they are in the preceding species. The tooth
is symmetrical, as in the largest teeth of Péychodus Mortoni, but it is propor-

tionately of less breadth transversely, and also higher.

299

The crown forms a prominent cone with evenly sloping sides, and with a
transversely oblong square base narrowing a little posteriorly. The posterior
sinus of the crown comports in its height and breadth with the proportions
of the former. ‘The principal ridges of the surface of the crown cross the
summit and posterior slope transversely. Descending, they branch in a
divergent manner and anastomose, so as to form a comparatively coarse retic-
ulation, extending to the borders of the crown. The reticulation covers the
anterior slope of the crown and the sinus posteriorly. The direction and
arrangement of the ridges resemble those in the European Péychodus decur-
rens, but in this the principal ridges are much coarser and more widely
separated. The root is mutilated in the specimen. ‘The transverse diam-
eter of the crown is 14 lines; its fore and aft diameter and its height about
1 inch.

Figs. 15, 16, Plate XVIII, represent two views of a small tooth, which
‘may probably belong to the same species. It is unsymmetrical, and is worn
away at the summit of the crown. The latter is proportionately less promi-
nent than in the large tooth, but has its ridges arranged in the same general
manner. The root is very thick in comparison with the size of the tooth.
The transverse diameter of the crown is 74 lines; the fore and aft diameter
4 inch, ©

_Of five remaining specimens, one is a smaller and unworn tooth nearly
like that last described. Its crown is‘ lines wide and 4 lines from before
backward.

The specimen represented in Fig. 17 is more symmetrical, and nearly
resembles in shape the smaller symmetrical teeth of Ptychodus Mortoni, as
represented in Figs. 13, 14. The apex of the crown is not so pointed, but is
prolonged fore and aft in an acute ridge, and the rugze of the surface are not
convergent, but cross the summit in the usual transverse manner of the other
teeth. The breadth of the crown in this specimen is 44 lines; the antero-
posterior diameter 3% lines. .

The remaining teeth, of which the largest is represented in Fig. 18, have
a transversely ovoidal crown slightly elevated to one side of the center. The
surface is crossed by rugz in the same manner as in the large teeth.

300

The méasurements of the three specimens are as follows:

Lines. Lines. Lines.
Transverse diameter of the crown .........--..---- ae i 34 24 2
Antero-posterior diameter of the crown ....-...-..-...--- 12 14 14

Prycuopus WHIPPLEYI.

Marcou, in his Geology of North America, describes and figures a tooth
from the Cretaceous formation near Galisteo, New Mexico, and refers it to a
peculiar species under the above name. .

A similar tooth submitted to my inspection by Dr. Benjamin F. Shumard.
from the Cretaceous rocks of Texas, is represented in Figs. 19, 20, Plate
XVIII. It is remarkable for the abrupt nipple-like prolongation of the
crown.

The tooth is unsymmetrical, and probably held a lateral position in the
series. ‘The base of the crown is quadrate, with the fore and outer borders
forming a single curve, while the other borders form a nearly right angle.
The nipple-like eminence of the crown inclines, as I suppose, outwardly.
The posterior sinus is shallow. The ruge of the surface of the crown cross
the summit transversely and diverge and branch descending upon the sides of
the cone. They are comparatively fegble, but this condition may be partially
due to friction. The surface of the base of the crown appears rather nodu-
lated than reticulated.

The breadth of the tooth at the base of the crown is 7 lines transversely
_and fore and aft; its height from the bottom of the root 8 lines.

The tooth resembles that of Ptychodus altior of Agassiz, from the chalk of
Sussex, England, as represented in Fig. 10, Plate XXX, of Dixon’s Geology
of Sussex.

ACRODUS. ~ |

This extinct genus of cestraciont sharks, first described by Agassiz, was
represented in Europe by many species whose remains occur in the various
formations from the Permian to the Cretaceous inclusive.

AcRODUS HUMILIS.

A species to which this name has been given is indicated by an isolated

-

301

tooth represented in Fig. 5, Plate XX XVII, magnified 14 diameters. The
specimen was obtained from the yellow limestone of the Cretaceous series,
-near Vincentown, Burlington County, New Jersey, and it belongs to the
Museum of the Academy. The crown of the tooth is 7$ lines by 24 lines.
The extremities are angular; the sides nearly straight or in the feeblest
degree. sigmoid. The upper surface is convex; and its median ridge is almost
obsolete. ‘The secondary ridges, proceeding transversely from the former,
become branched and finely reticulated at the boundaries of the crown.
The groove on the inner side of the latter, for co-adaptation to the contig-
uous tooth, is about three-fourths of a line in width. The fang or con-
tracted base of the tooth is about half the breadth of the crown.

Professor Emmons has represented the tooth of an Acrodus in Fig. 97 of
his Report of the North Carolina Geological Survey for 1858, which he attrib-
utes to the Miocene Tertiary. If it really pertains to this formation, it indi-
cates the latest known species of the genus. The species has been named
Acrodus Emmons

GALEOCERDO.

GALEOCERDO FALCATUS.

The teeth of Galeocerdo are nearly as broad as they are long, and the root
is but moderately notched. The anterior border of the crown is strongly
arched and oblique; the posterior border is slightly curved and nearly verti-
eal, but is abruptly prolonged backward at its base. The borders of the
crown are serrated; the point is somewhat acuminate.

Teeth from the chalk formations of Europe figured in the “ Poissons Fos-
siles,” and ascribed by its illustrious author to half a dozen different species, ©
are, with reason, by Reuss referred to a single one with the name of Coraz
heterodon. As Agassiz, according to Gibbes, does not now consider Coraz
’ different from G'aleocerdo, I have used this name, together with the earlier
specific one of falcatus, to represent the Corax heterodon of Reuss.

Many specimens of well-preserved teeth, submitted to my examination,
from various localities of the American Cretaceous formation, appear to belong
to Galeocerdo faicatus. The variations in the form and size of different teeth
I think are sufliciently accounted for from the difference of position the teeth
occupied in the jaws and upon difference in age.

Figs. 29 to 31, Plate XVIII, represent three of these teeth, obtained with

302

others by Dr. George M. Sternberg, United States Army, from the vicinity
of Camp Supply, on the North Canadian River, Indian Territory, probably
from a formation of Cretaceous age.

Their apparent specific identity with the teeth of Galeocerdo falcatus of
Europe is seen by comparing the figures with Fig. 43, taken from a tooth
imbedded in a block of chalk from Sussex, England.

Figs. 32 to 36 represent a series of similar teeth obtained, with many others
of the same character, by Dr. William Spillman, from near Columbus, Mis-
SISSIppl.

Figs. 37 to 40 represent smaller teeth, which I suspect to belong to the
same species, found by Dr. John L. Leconte, about three miles east of Fort
Hays, Kansas. Similar specimens were also obtained by Dr. Hayden, in
bed No. 2 of the Cretaceous rocks, near the mouth of Vermilion River,
Kansas.

Figs. 41, 42 represent small teeth, likewise of the same species, obtained
by Dr. Shumard from the Cretaceous formation of Texas.

OXYRHINA.

The teeth of Oxyrhina have a simple, compressed demiconical crown, with

sharp borders, and without lateral denticles.
OXYRHINA EXTENTA.

Figs. 21 to 23, Plate XVIII, represent specimens of teeth of an Oxyrhina
discovered by Dr. George M. Sternberg, United States Army, in the vicinity
of Camp Supply, on the North Canadian- River, Indian Territory. Figs. 24,
' 25 represent similar teeth found by Dr. William Spillman_in the Cretaceous
formation near Columbus, Mississippi. These teeth differ especially, from
those of other species previously described and figured, in the greater pro-
portionate extension laterally of the base of the crown. They most nearly .
resemble the teeth of the Oxyrhina Mantelli of the chalk of Europe.

In the Museum of the Academy of Natural Sciences of Philadelphia there
is a specimen of an Oxyrhina tooth in a block of chalk from Susséx County,
England, resembling those just described in the unusual extension laterally
of the crown. If this specimen pertained to O. Mantelli, it is probable that
the specimens from Mississippi and the Indian Territory do likewise. It

was not until after I had described the latter under the above name that I

208

noticed the specimen from the English chalk. My comparisons had been
made with the figures of Agassiz, Dixon, and Reuss, and in none of these do
the teeth exhibit so conspicuous a lateral extension of the base of the crown
as in the American specimens and the English chalk specimen of our Museum.
An exception to this statement may be made in reference to Fig. 26, Plate
XXX, in Dixon’s Geology of Sussex, representing a tooth, which is referred

to Lamna acuminata.
Measurements of the specimens referred to Oxyrhina extenta are as follows:

k |
Specimens represented in Plate XVIII. Fig. 21. | Fig. 22. | Fig. 23. | Fig. 24. | Fig. 25.
Lines. Lines. Lines. Lines. Lines.

Hengsth from notch of root.-....--..----|-.- Sa ee 24 84 ee es A
Length of crown at middle ........-..- sn SUseM a vele 8 64 10 84
Breadth of crown at base -.......-.-.-- 9 1 12 164 13
rerun Ol COO 23.5.2 022-2 <-22--% sees 12 Li 13 18 14
Thickness of root....-..-.. Ri ele ce th 5 4g 44 5 4

LAMNA s, OXYRHINA.

The teeth of Lamna are in general characterized by the long, narrow
crown, with a single denticle on each side of the base, and a strong root with
narrow branches separated by a deep notch ‘Those of Oxyrhina usually
have a broader crown without lateral denticles, and also have a broader root
with a shallower notch. In both genera, however, the proportion of breadth
to length, and most other characters, except the presence or absence of the
lateral denticles, vary in different parts of the jaws. In both, the side teeth
are wider than those in advance, the disproportion usually being greater in
Oxyrhina-than in Lamna. Some of the teeth in the two genera so nearly
assume the form of one another, that when isolated fossil teeth of either are
found without the base it is sometimes difficult to know to which to refer
Svoem.

A number of times I have seen specimens of teeth, reputed to have been
derived from the Cretaceous formation, which so closely resemble those of
certain Tertiary species of Lamna, except in the possession of. lateral denti-
cles, that I have suspiciously regarded them as pertaining to the same. The
absence of denticles I thought might be accidental or abnormal. The report

that the teeth had been found in a Cretaceous formation I suspected might

304.

be a mistake; or, if they had, that they were, perhaps, accidental in their
occurrence in that formation, and had probably been derived from some con-
tiguous Eocene deposit. The frequent repetition of the same thing has led
me to view the specimens as having really pertained to Cretaceous fishes.
The absence of the lateral denticles would refer the teeth to the genus Oxy-
- rhina, and the general form and other characters rather to the genus Lamna.
May the teeth not be regarded as Rane belonged to Oxyrhina ancestors of
some of the later Lamne ?

Fig. 44, Plate XVII, represents a tooth which lies imbedded in a portion
of gray rock, obtained by Dr. John L. Leconte from the Cretaceous forma-
tion three miles east of Fort Hays, Kansas. The specimen is perfect and
unabraded. In all respects it is like the teeth of Lamna cuspidata of the
early Tertiary deposits, except that it is devoid of lateral denticles, and pre-
sents no trace of ever haying possessed them.

Fig. 45 represents a tooth, which lies in a block of chalk, from Sussex,
England. ‘The specimen is preserved in the Museum of the Academy of
Natural Sciences of Philadelphia. Like the former, it closely resembles the
teeth of LZ. cuspidata, but exhibits no trace of lateral denticles.

Figs. 46, 47 represent two teeth which the writer found with the skeleton
of Hadrosaurus Foulkii and shells of Exogyra costata, Ammonites placenta,
&e., in clay near Haddonfield, Camden County, New Jersey. These speci-
mens, unworn and perfect, except in positions having no relation with the
point in question, are identical in character with the teeth of Lammna-elegans
of the early Tertiary deposits, except that they exhibit no trace whatever of
the existence of lateral denticles.

Figs. 48, 49 represent two teeth selected from eight specimens obtained
by Dr. William Spillman from the Cretaceous formation near Columbus, Mis-
sissippl. Most of the specimens are complete and well preserved, and in no
instance exhibit traces of lateral denticles, while in all other respects they are
like the teeth of L. elegans.

Seven specimens of teeth from the Cretaceous formation ef Green County,
Alabama, presented to the Academy of Natural Sciences of Philadelphia by
Dr. Joseph Jones, also agree with those of L. elegans, except that they have
‘no lateral denticles.

In a collection of similar teeth, presented to the Academy by William M.
Gabb, in all the specimens retaining the root, twenty in number, the lateral

305

denticles are absent. Most of the teeth appear slightly water-worn, but the
best of them exhibit no trace of the lateral denticles. 'These specimens were
obtained by Mr. Gabb from the Cretaceous green sand of Mullica Hill, Glou-
cester County, New Jersey.

Fig. 50 represents a tooth which lies partially imbedded in a fragment of
gray sandstone, obtained by Professor Hayden from the Cretaceous deposit,
indicated by him as No. 2, near the mouth of Vermilion River, Kansas. In
the attempt to dislodge the tooth from its matrix the ends of the root were
broken off, but it is otherwise complete. It also appears not to have pos-
sessed lateral denticles, but-otherwise is like the teeth of L. elegans.

Roemer describes and figures a tooth, (Kreidebildungen v. Texas, page 29,
Plate I, Fig. 7,) under the name of L. Texana, from the Cretaceous forma-
tion of Texas. The figure represents what appears to be a perfect tooth
without lateral denticles, and otherwise resembles those of L. elegans.

Dr. B. F. Shumard also submitted to my inspection several teeth from the
- Cretaceous formation of Texas resembling those of LZ. elegans, but in these
the root was broken off, excepting on one side of one specimen, and in this
no lateral denticle existed.

Notwithstanding all that has been stated above, I must add that I have
noticed among collections of teeth of ZL. elegans from Tertiary formations
specimens in which the lateral denticles were feebly developed, and others in
which they were entirely absent. In some of the latter, traces of their acci-
dental detachment were perceptible, but in others I could see none.

It would appear, however, from the facts thus given, that during the Cre-
taceous period there existed two species of sharks in which the teeth resem-
bled those of L. cuspidata and L. elegans of the Tertiary period, except that
the teeth possessed no lateral denticles. The two Cretaceous sharks were
probably the ancestors from which the species just named were evolved.

OTODUS.
OTODUS DIVARICATUS.

Among a small collection of fossils submitted to me for examination by Dr. -
William Spillman, of Columbus, Mississippi, there is a specimen of a shark-
tooth of rather peculiar character, which is represented in Figs. 26 to 28, of
Plate XVIII. The specimen is labeled ‘“ lime formation,” Texas, and noth-

39 G

306

ing is further known in relation to its locality, but I suspect it to be of Cre-
taceous age. Of known species, it bears most resemblance to the teeth of
Otodus semiplicatus, Ag., of the chalk of Europe. It also has some likeness
with a tooth from the chalk of France, represented in Fig. 11, Plate LX XVI,
of Gervais’s Paleontologie Frangaise.

The crown forms a narrow demicone, with an expanded base supporting a
pair of inwardly-diverging denticles. The surface of the principal cone near
the base is plicated. The root is thick and deeply notched, and extends pos-
teriorly more than half the length of the tooth. The anterior surface of the
crown in the median line is as long as the base is wide, and is about one-fifth
greater than the posterior surface.

The measurements of the specimen are as follows :

Lines
Length of tooth atmiddle 2. 225 one. a fay ee ee ae 16
henge th from ends of the root. -.---2-.- -----~ -- = n= ae ne 21
Breadth at ends of the root..-.-.- lay ee seas iicks ioe Ne ee eee -.. 15
Length of crown in front ...-.. - oe SRS ae ROSA A Lea e far or Laieis nite re wee
Length of crown behind ........ i ae Saye wee G's ye teaw she heen oo 10
Breadth of trewn at base <2... [2-222 37sec. seme ee one ae = eer 123
Folocephate.
EDAPHODON.

In the extinct chimeeroid fish Edaphedon the inferior maxillaries are pro-
duced anteriorly in a long beak, and the superior maxillaries are provided
with three large dental areas. In the allied genus Ischyodus the inferior
maxillaries are not prolonged in a beak, and the upper ones are provided with
four large dental areas.

EDAPHODON MIRIFICUS.

A species under the above name was indicated by the author in the Pro-
ceedings of the Academy for 1856, page 221. It was founded on eight speci-
mens of maxillaries obtained from the Cretaceous green sand of Burlington
County, New Jersey, by Professor George H. Cook, during the State geo-
logical survey.

The inferior maxillaries, represented in Figs. 6 to 9, Plate XX XVII, are
about twice the length of the depth. The two rami converge in a curve, and
end together in a long, bird-like beak, (Fig. 6.)

The outer surface (Fig. 7) of each ramus is lozenge-like in outline, defined

307

by a concave upper border, a convex anterior border, a short, oblique, poste-
rior border, and a convex lower border. The surface is concave longitu-
dinally, and is convex transversely in front and behind, and concave in the
middle.

The inner surface (Fig. 8) is flat transversely, slightly convex longitudin-
ally, and with the fore and back borders prominent. It is moderately stri- —
ated in the length, and at its upper part presents a symphysial bevel, extend-
ing the length of the beaked portion of the bone.

The oral surface (Fig. 6) on the beak is concave fore and aft, and at the
back half of the bone forms a lozenge-like plane sloping inwardly, and having
the outer borderelevated. The sloping plane exhibits at its fore part inter-
nally a large cordiform dental area, with the notch at the base of the beak.
Externally to this area, near the fore part of the crest defining the outer part
of the sloping plane, there is a second much smaller elliptical dental area.
These two areas are separated by a groove, widening forward upon the oral
surface of the beak, where it presents a third dental area. This is the third
in size, is oval in form, and is situated just in advance of the outer part of the
largest dental area.

A fourth area, smaller than the others, occupies the back extremity of the
symphysial bevel to the inner side of the anterior part of the largest dental
area. The dental column which forms this fourth area produces the prom-
inent ridge defining the inner surface of the ramus mandibuli posteriorly.

Beside these dental areas, two or three others are observed at the end of
the beak. One of them curves from the symphysis outward and backward on
the outer edge of the point of the beak. Another smaller oval one is situated
at the edge of the symphysis behind the commencement of the former. In
one specimen a still smaller oval area is situated just behind the outer end of
the curved area, but in the other specimens it appears not to be distinct from
the latter.

The dental areas in the fossils appear.as depressed and decomposed,
friable, white, chalky tracts, with harder calcigerous tubules of the vaso-
dentine projecting from the surfaces. The tubercular eminences originally
occupying the position of the areas and terminating the dental columns
have disappeared, leaving depressed surfaces. The vaso-dentinal columns
corresponding with the areas on the triturating surface are visible at the

posterior-inferior extremity of the mandibles, as seen in Fig. 9.

308

The upper maxillaries, represented in Figs. 10 to 12, bear a near resem-
blance to those of Ldapniodon Bucklandi and E. leptognathus, as represented
in Tab. 40 d, of the third volume of the Atlas of Agassiz’s Poissons Fossiles.

The outer surface (Fig. 11) of each maxilla is a broad, sloping plane, the
inner surface a vertical plane. The upper surface is also flat, but is occupied
at its inner back part by a wide, deep gutter, ending forward in a pit.

The palatine surface (ig. 10) of the two bones conjoined at its back part
forms a wide, transverse concavity, nearly flat in the middle, but curving
downward at the outer part. The palatine surface inclines forward to the
anterior subacute termination of the bones. The lateral border of each max-
illa at the palatine surface is strongly sigmoid.

Three large dental tubercles occupied the palatine surface of each max-
illa, indicated in the fossils, as seen in Fig. 10, by three depressed areas of
white, decomposing vaso-dentine. The largest area is posterior and internal.
It is broken at its back part in the fossils, but, in the entire condition, appears
to have been reniform in outline. Immediately in advance of this area is
another with an oblong cordiform outline; and external to the largest one is
the third area, about as long as this, but not more than half the breadth, and
having a clavate outline.

The dental columns corresponding with the three dental areas are seen
-at the back of the maxille, the largest one below the position of the two
smaller ones, as represented in Fig. 12.

The measurements of the specimens are as follows:

Inferior maxillary.

Lines
Hxtremeleneth of bone 50 a2cen ite 2402: 1a 5 tee eee 64
hength of beak along the symphysis... -...2..c-.-+---.2------ =e eee 40
Length of anterior border Of ramus. -.. =<... -7 - 2250552 o nen - 3) 44
Length of posterior or upper border back of the beak ........--............... 26
Width. of inner surface 2. 20sec ast. oe ee eine oe eee cio ee eee oe 26
Width of upperisurface back of the beak.:...5.----- 02. ..-.06..- --.= === eee 24
Width of the large postero-internal dental area............-.-...-...--.---..<5 13*
Estimated breadth fore andaft.-- 3.52222 =- 2222+ esse ee = 16
Width. of external dental jarea..4..5. 23582262 eeeene 4s ee eee 2 oe vi
Tistimated breadth fore and aft.......-.--.-..---- jee eres sshecee oe 3
Diameter of anterior dental area fore and aft--.-. - deese Peele oe a ae
Diameter of same transversely -..--.--..------ eno we aeot waka > tee ee 3)

*The size of the dental areas is in some measure uncertain, as in some cases they appear to have
been more or less extended in the fore and aft diameter by fracture over the position of the dental
columns.

309

Superior maxillary.

Lines.
Extreme length of bone ..........--.-.--.. igi ie apt lig Nemes, Sy. Napanee 2 a earraee wee 58
PAST iToMmuOMe mmMbermalliye seis, lea 8) fee AISI AS ok eS Barc Pe he See ee he SE 43
SECT, TDS LOTTA ae ee eI ae ee ee, SS Rt ee Be a ee em ee 23
Diameter fore and aft of large postero-internal dental area .....-...--.-.-....-- 18
Wiameter of same transversely. ....605.-: 0-20 2.2 2. ee ee re ab ee See 12
Diameter fore and aft of anterior dental area..-...----..4--- .22-.-22--52-+---- At
Diameter of same posteriorly and transversely ..-....---.--.--.----+---+------- 5
Diameter fore and aft of external dental area .....-....-..----- .-.-------.--- 16
Diameter transversely of the same where widest......-.-.--.-....--------.--- 5

EUMYLODUS.
EUMYLODUS LAQUEATUS.

Among some fossils from the Cretaceous sandstone near Columbus, Missis-
sippi, submitted to my examination by Dr. William Spillman, there is a spec-
imen of the maxillo-dentary apparatus of a chimeroid fish, related with
Ischyodus, but apparently distinct from that genus. The specimen is repre-
sented in Figs. 21, 22, Plate XIX, and Figs. 13, 14, Plate XXXVIL_ It
most resembles, in its general form, the mandible of Ischyodus, as repre-
sented in Fig. 20, Tab. 40, of £ Townsendi, and Fig. 16, Tab. 40 c, of
Agassizi, of the third volume of the Atlas of the Poissons Fossiles.

The bone is of denser character than the corresponding one of Edaphodon,
and in this respect and several others is more like that of Leptomylus, de-
scribed by Professor Cope.

The outer surface (Fig. 14, Plate XX XVII) is nearly flat; but slightly
depressed below, and bent outwardly behind from the triturating surface.
The inner surface (Fig. 21, Plate XIX) is fluted; the anterior third presents
a succession of three curved ridges separated by two grooves; the median
third forms a wide, concave groove ; and the posterior third forms a nearly
square plane, sloping from the triturating surface backward and inward, and
defined by a subacute border from the outer surface of the bone.

The anterior border of the mandible appears as curved cylindroid termina-
tion of the bone. No appearance of a distinct symphysial surface exists.

The oral surface (Fig. 22, Plate XIX) is uneven, and conforms in its out-
line with the inner and outer faces of the bone. The anterior most promi-
nent portion is convex, and exhibits some scratches and polish, due to its
masticating function. Its posterior two-thirds incline from a median dentary

ridge, moderately without and behind, but steeply within.

310

The dentary ridge is near the median line of the oral surface, extending
about half its length, but nearer its posterior than anterior extremity. As
seen in Fig. 13, Plate XX XVII, it appears to be composed of the prominent
tubercular extremities of three connate columns, of which the back two
appear oval, and the anterior one rather clavate in outline.

The measurements of the specimen are as follows :

; Lines
Length ‘or depth of the anterior border... 2-0). < 2-22-22...) ee 32
Length or depth of the posterior border.. -- ....--.-...-..-. te ee a aan 11
Thickness of the anterior column or border.....--....----.. eee 6
Thickness at the second ridge of the inner surface ..............-.. . ae 64
Thickness at the third ridge of the inner surface...-.-.-.... ...+..-.---.-...- 83
Thickness at the middle concavity of the inner surface .......-.-..-.-......... 74
Thickness at the commencing ridge of the posterior slope of the inner surface... 10
Fore and aft extent of triturating surface......2-..--:.-2--.-5--5. --=2eeeeeee 36

Length of dental tract 5:26.25. 55.82.5522 2022 seine eke ee eee ee 19

NOTICE OF SOME REMAINS OF FISHES FROM THE CARBONIF-
EROUS FORMATIONS OF KANSAS.

The remains described below were obtained by Dr. F. V. Hayden and
Mr. F. B. Meek in the summer of 1858, and were originally noticed by the
writer in the Proceedings of the Academy of Natural Sciences of Philadel-
phia in January, 1859.

Plagiostom.
CLADODUS.
CLADODUS OCCIDENTALIS.

The extinct genus of cartilaginous fishes, Cladodus, was first characterized
by Agassiz from isolated teeth from the Coal-formation of Europe. A
species of the same genus is indicated by a fragment of a tooth discovered
by Messrs, Hayden and Meek in the upper Coal-measures of Manhattan
Kansas.

The specimen has lost one-half its base, a large portion of its principal
cusp, and the points of the lateral cusps, but sufficient remains to give us a
correct idea of the form of the perfect tooth, as represented in Figs. 4 to 6,
Plate XVII.

The base of the tooth is oblong in outline, with the inner border some-
what angular and the outer one concave. Its upper inner surface slopes from
the cusps, and near its margin, a short distance from the extremities, supports
a pair of oval tubercles. Similar protuberances occupy a position beneath
the base externally.

The median or principal cusp of the tooth is elongated demiconical, with
acute lateral edges. The inner convex surface of the cusp at its base exhibits
sharp, oblique folds or striz, as represented in Fig. 4. The outer less convex
or nearly flat surface is smooth, except a few vertical wrinkles at its base.

The lateral denticles on each side of the principal cusp are two, of which
the outer is the larger.

312

In its perfect condition the tooth has approximated 14 inches in length,
and about 1 inch in breadth at base.

A similar tooth from the coal-measures of Illinois has been described
under the name of Cladodus mortifer by Professor Newberry in the second
volume of Worthen’s Geological Survey of Illinois, published in 1866. Mr.
Orestes St. John has likewise described some teeth of the same species from
the coal measures of Nebraska, in the Proceedings of the American Philo-
sophical Society for 1870, and in Hayden’s Report on the Geological Survey
of Nebraska, published this year.

XYSTRACANTHUS.
XYSTRACANTHUS ARCUATUS.

A second cartilaginous fish of the Coal-period is indicated by a remarkable
dorsal spine, discovered by Messrs. Meek and Hayden in the Upper Carbon-
iferous rocks of Leavenworth City, Kansas. The specimen, represented in
Fig. 25, Plate XVII, lies partially imbedded in a piece of yellowish lime-
stone, also containing a few minute crinoid segments. The point of the spine
and its root of- insertion are destroyed, and the specimen is otherwise muti-
lated and appears somewhat crushed, but it is sufficiently characteristic to
distinguish it from ichthyodorulites previously described.

The spine is strongly curved, appears flattened at the sides, and is rounded
at the borders. Its transverse section is narrow ovoid, with the narrower
extremity toward the convex border. The spine is longitudinally striated,
and in its present condition the bone is brown and quite friable. The sides
and concave border of the spine are furnished with white, shining, enamel-
like tubercles of various sizes. The smaller ones are half ovoid; larger
ones are conical or half conical; and the largest, which occupy the upper and
lower part of the concave border, are crescentoid, and embrace the latter. In
shape and attachment the larger tubercles remind one of minute polypori
projecting from=the stem of a tree. They are convex above, and flat, or
slightly concave, below.

PETALODUS.
PETALODUS ALLEGHANIENSIS.

Petalodus is another extinct genus of cartilaginous fishes, allied to our
living sharks, which was originally characterized by Owen, and was also
established on isolated teeth from the Carboniferous formations of Europe.

313

A species of the same genus, under the above name, was described by the
author in the Journal of the Academy of Natural Sciences for 1856, from a
specimen found in the Coal-measures of Blair County, Pennsylvania. A sim-
ilar tooth was also described and referred to the same species in the Pro-
ceedings of the Academy for 1859, which was obtained by Messrs. Meek and
Hayden from the Upper Carboniferous formation of Fort Riley, Kansas. The
specimen is represented in Fig. 3, Plate XVII.

The crown is broad, and somewhat lozenge-shaped in outline. The base
is bordered by a thick annulated ridge, arching downward toward the middle
and moderately deflected at the extremities. The free border is sharp and
somewhat arcuate, and the apex is slightly acuminate. The anterior sur-
face of the crown slopes outwardly. ‘The posterior deeper surface is concave
at its lower median portion. The fang is about as long as the crown is exter-
nally, but is not so wide. Its extremity is angular and everted.

The measurements of the tooth are as follows :

Lines
Length of tooth in the entire condition about...........-.2.-.. 0.2.2. .0-..00-- 19
2 Se wills (OV (CERO OAG TR CE Te eee a ee 20
fore s G/L GIP GLAD Wl Ge 9 0 Nh se eee sae ee eee a 93
TOE EN ORC RO VAT 16 1h a ee a a 12
Eee permet Te XPOS Hele aisle sesh wise oes ccs toe wale, cieie wis ee sna siomet 94
Tee PiGIL) CI TEI TPES 8 oie eal ae erg ere oy ea oe, ey ee oe 14

Similar teeth from the Coal-measures of Illinois have been described by
Professor Newberry, under the name of Petalodus destructor, in the work
above mentioned. Others have also been described or indicated, from the
Coal-measures of Indiana, Iowa, and Nebraska, by Mr. St. John, likewise in
the works above named.

ASTERACANTHUS.
ASTERACANTHUS SIDERIUS.

Incidentally, I take the opportunity of describing a fossil submitted to my
examination by Professor J. M. Safford through Professor Hayden. It was
obtained near Glasgow, Tennessee, and is reputed to be of Sub-carboniferous
age. ‘I'he specimen consists of a fragment of an ichthyodorulite, or fossil-
fish spine, and is represented in Fig. 59, Plate XXXII. It appears to indi-
cate a species of the extinct genus Asteracanthus, the remains of which had
previously only been found in formations of later age than that above men-
tioned.

40 @

314

The fragment is from an intermediate position at the junction of the root
and shaft, and is a little over 3 inches in length. It looks as if when ina
complete condition it had been upwards of a foot in length, approximating
that of the dorsal spine of A. ornatissimus. Broken off at both extremities,
and also posteriorly, so as to leave no portion of the usual groove, it appears
as a solid, porous bone-fragment, triangular in transverse section toward the
apex, and oblong toward the root.

The sides of the shaft are closely studded with nama tubercles,
arranged in rows directed upward and forward. 'The tubercles incline in the
same direction, and have their sides longitudinally striated. Their summits

are worn away, the extent of abrasion increasing, approaching the anterior
border of the spine.

SYNOPSIS OF THE EXTINCT VERTEBRATA DESCRIBED OR
NOTICED IN THE PRESENT WORK.

MAMMALIA.
Carnivora. 2
FELIDZz.

FELIS.
FELIS AUGUSTUS.
Leidy: Pr. Ac. Nat. Se. 1872, 39.
Described page 227 of the present work, and represented by Figs. 18, 19,
Plate VU, and Fig. 24, Plate XX. From the Pliocene of the Niobrara
River, Nebraska.

FELIS IMPERIALIS.
Founded on an upper-jaw fragment, containing the second premolar tooth,
from the Quaternary of California. Described page 228, and represented
by Fig. 8, Plate XXXT.

CANID&.

. CANIS.
CANIS INDIANENSIS.
Leidy: Ext. Mam. of N. America 1869, 368.
Canis primevus. Leidy: Pr. Ac. Nat. Sc. 1854, 200; Jour. Ac. Nat. Se. 1856,
ILI, 167, Plate XVI, Figs. 11, 12.

Founded on an upper maxillary with teeth from the banks of the Ohio,
near Evansville, Indiana. Also indicated by the ramus of a lower jaw
from California. Quaternary.

See page 230 for description of the latter specimen, represented by Fig. 2,
Plate XX XI.

CANIS VAFER.
Leidy: Pr. Ac. Nat. Se. 1858, 21; 1870, 109; Ext. Mam. of N. America 1869, 368.

Founded on jaw-fragments with teeth from the Pliocene of the Niobrara
River, Nebraska, and Sweetwater River, Wyoming.

316

FAMILIES UNDETERMINED.
PATRIOFELIS.
PATRIOFELIS ULTA.

Leidy: Pr. Ac. Nat. Se. 1870, 10; Hayden’s Rep. Geol. Sur. Wyoming 1871, 344;
Hayden’s Rep. Geol. Sur. Montana 1872, 355.

Founded on the mutilated rami of a lower jaw from the Bridger Eocene
Tertiary, Wyoming. Described page 114, and represented by Fig. 10,
Plate IT.

UINTACYON.

Probably the same as Miacis, described by Professor Cope in the Proc.

Am. Phil. Soc. 1872, 470.
UINTACYON EDAX.
Leidy: Pr. Ac. Nat. Se. 1872, 277.

Founded on the ramus of a lower jaw from the Bridger Eocene Tertiary
of Wyoming. Described page 118, and represented by Figs. 6 to 10,
Plate X XVII.

UINTACYON VORAX.
Leidy: Pr. Ac. Nat. Se. 1872, 277.

Founded on a lower-jaw fragment from the Bridger Eocene Tertiary of
Wyoming. Described page 120, and represented by Figs. 11 to 13,
Plate XXVII.

SINOPA.

SINOPA RAPAX. .
Leidy: Pr. Ac. Nat. Se. 1871, 115; Hayden’s Rep. Geol. Sur. Montana 1872, 355.
Founded on a lower-jaw fragment with teeth from the Bridger Eocene
Tertiary of Wyoming. Described page 116, and represented in Fig. 44,
Plate VL.

SINOPA EXIMIA.

Indicated by a lower-jaw fragment, described page 118, and represented
in Fig. 45, Plate VI. From the Bridger Eocene Tertiary of Wyoming.

MusTELIDz.
LUTRA ?
LuTRA PISCINARIA.
Indicated by a tibia, described page 230, and represented in Fig. 4, Plate
XXXI. From the Pliocene Tertiary of Idaho.

al7

ARTIODACTYLA.
Ruminantia.

CAMELIDZ.
AUCHENIA.

AUCHENIA HESTERNA. |
Founded on specimens of teeth described page 255, and represented in
Figs. 1 to 3, Plate XXXVII. From the Quaternary of California.

PROCAMELUS. s. Protocamelus.
~PROCAMELUS OCCIDENTALIS ?
Leidy : Pr. Ac. Nat. Sc. 1858, 23, 89; Ext. Mam. N. America 1869, 382.

See page 258 of the present work, and represented by Figs. 21, 22, Plate
XX. Pliocene of Nebraska and Texas!

PROCAMELUS ROBUSTUS !
Leidy: Pr. Ac. Nat. Se. 1858, 89; Ext. Mam. N. America 1869, 381.

See page 259 of the present work. Pliocene of Nebraska and Texas.

PROCAMELUS VIRGINIENSIS.
Leidy: Pr. Ac. Nat. Se. 1873, 15.

Page 259, and represented by Figs. 26 to 29, Plate XXVII. Founded on

teeth from the Miocene of Virginia.

PRocAMELUS ? NIOBRARENSIS.

Megalomeryx niobrarensis? Leidy: Pr. Ac. Nat. Se. 1858, 24; Ext. Mam. Da-
kota and Nebraska 1869, 161, Plate XIV, Figs. 12 to 14.

See page 260, under the name of Megalomeryx niobrarensis? and repre-
sented in Figs. 24, 25, Plate XXVIII. Founded on teeth from the Plio-
cene of the Niobrara River, and from L’Eau qui Court County, Ne-
braska. |

CERVIDZ.

LEPTOMERYX.

LepromMeryx EVANSI.
Leidy: Pr. Ac. Nat. Se. 1853, 394; 1870, 112; Ext. Mam. N. America 1869, 383+

Noticed from the Miocene of Oregon, page 216. Originally described
from the Miocene of Dakota. ,

318

MERYCODUS
MERYCODUS NECATUS.
Leidy: Pr. Ac. Nat. Se. 1854, 90, 157 ; 1857, 89; 1858, 23; 1870, 109; Ext. Mam.
N. America 1869, 382.

Noticed from the Pliocene of Sweetwater River, Wyoming. Originally
described from Bijou Hill and from Little White River, or the South
Fork of White Earth River, Dakota.

Bovipz.

BISON.

BISON LATIFRONS. .
Leidy: Pr. Ac. Nat. Se. 1852, 117; Mem. Ext. Sp. American Ox in Smiths. Con-
trib. 1852, 8; Ext. Mam. N. America 1869, 371.
Noticed from the Quaternary of California and Pennsylvania, page 253, and
represented in Figs. 4 to 8, Plate XXVIII.
Found in the Quaternary of Pennsylvania, Georgia, South Carolina, Ken-
tucky, Mississippi, Texas, and California.

OREODONTIDZ.
OREODON.

Leidy: Pr. Ac. Nat. Se. 1851, 238.
Merycoidodon. Leidy: Pr. Ac. Nat. Se. 1848, 47.

OREODON CULBERTSONI.
Leidy :. Owens’s Rep. Geol. Sur. 1852, 548; Ext. Mam. N. America 1869, 379;
Pr. Ac. Nat. Se. 1870, 67, 112.
Noticed from John Day’s River, Oregon, page 211, and TepiesesE st in
Fig. 12, Plate VII.

Professor Marsh has recently desenbed some remains from the Miocene of
Oregon, under the name of Oreodon occidentalis. (Am. Jour. Se. May,
1873.) He observes that it resembles O. Cudbertsoni in most of ‘its
cranial characters, but differs materially in the large auditory bulle.
From this, [ suspect the remains, together with those I have described
from Oregon under tke last-mentioned name, belong to the species I
have elsewhere named O. bullatus.

Professor Marsh observes that, ‘‘in comparing the various species of Oreo-
don, some new points in the structure of the genus were observed.” He
then gives in the formula of dentition the number of incisors as }, canines
t, premolars 4, molars 3, and adds: ‘‘The caniniform tooth of the lower

319

jaw is clearly the first premolar, as Dr. Gill has stated.” As may be
seen by referring to pages 84 and 85 of the Extinct Mammalia of Dakota

and Nebraska, although giving the formula of dentition of Oreodon as—

incisors %, canines +, premolars %, molars 3, I observe that the inferior

canine is a transformed premolar, and that the inferior lateral incisor, as
in other ruminants, is to be regarded as an incisiform canine.

OREODON SUPERBUS.
Leidy: Pr. Ac. Nat. Se. 1870, 111.

Described page 211, and represented by Fig. 1, Plate 1; Fig. 16, Plate I;
and Figs. 7 to 11, Plate VIL. From the Miocene of Oregon.

MERYCOCHGERUS.

Leidy: Pr. Ac. Nat. Se. 1858, 24; Ext. Mam. N. America 1869, 380.

MERYCOCHGRUS RUSTICUS.
Leidy: Pr. Ac. Nat. Sc. 1870, 109.

Described page 199, and represented by Figs. 1 to 3, Plate III; Figs. 1
to 5, Plate VII; and Figs. 9 to 11, Plate XX. From the Pliocene of
Sweetwater River, Wyoming.

AGRIOCHCERUS.

AGRIOCHERUS ANTIQUUS. ;
Leidy: Pr. Ac. Nat. Se. 1850, 121; Ext. Mam. N. America 1869, 381; Pr. Ac.
Nat. Sc. 1870, 112.

Noticed from the Miocene of Oregon, page 216.

AGRIOCHGRUS LATIFRONS.
Leidy: Pr. Ac. Nat. Se. 1867, 32 ; 1870, 67; Ext. Mam. N. America 1869, 381.

Noticed from the Miocene of Oregon, page 216.

Omnivora.
SuIDzA.

DICOTYLES.

DIcoTYLES PRISTINUS.
Peccary. Leidy: Pr. Ac. Nat. Se. 1870, 112.

Described page 216, and represented by Figs. 13, 14, Plate VII. From
the Miocene of Oregon.

320

ANTHRACOTHERID&.

ELOTHERIUM.

Pomel: Bibl. Univ. Genéve, Archives, 1847, 307.
Entelodon. Aymard: Mem. Soe. Agric., &c., du Puy 1848, 240.
Archeotherium. WLeidy: Pr. Ac. Nat. Se. 1850, 90.

ExoruertumM Morton?
Leidy: Pr. Ac. Nat. Se. 1857, 175; Ext. Mam. N. America 1869, 388.
Noticed from Wyoming, page 125, and represented by Figs. 28, 29, Plate
VII.

. KLOTHERIUM IMPERATOR.

Inferred from several mutilated teeth from the Miocene of Oregon, de-
scribed page 217, and represented in Figs. 3, 4, Plate IL, and Fig. 27,
Plate VIL Supposed to be the same as KE. superbum in Pr. Ac. Nat.
Se. 1870, 112.

ELOTHERIUM INGENS.
Leidy: Ext. Mam. N. America 1869, 388; Pr. Ac. Nat. Se. 1870, 112.

Noticed from the Miocene of Oregon. Originally from the Miocene of
White River, Dakota.

FAMILIES UNDETERMINED.
HYOPSODUS.
HYoPSoDUS PAULUS.
Leidy: Pr. Ac. Nat. Se. 1870, 110; 1872, 20; Hayden’s Rep. Geol. Sur. Wyo-
ming 1871, 354; Hayden’s Rep. Geol. Sur. Montana 1872, 363.
To this species, described page 75, I refer Figs. 1 to 9, 18 to 22, Plate VL
From the Bridger Eocene of Wyoming. .

HyopsoDUS MINUSCULUS.
This species, described page 81, is represented by Fig. 5, Plate XXVII.
From the Bridger Eocene of Wyoming.

MICROSYOPS.

Leidy: Pr. Ac. Nat. Se. 1872, 20; Hayden’s Prelim. Rep. Geol. Sur. Montana
1873, 363.
Limnotherium. In part of Marsh: Am. Jour. Se. 1871, II, 42.

Microsyors ELEGANS.
LTimnotherium elegans. Marsh: Am. Jour. Se. 1871, I, 43.
Microsyops gracilis. Leidy: Pr. Ac, Nat. Se. 1872, 20; Hayden’s Prelim. Rep.
Geol. Sur. Montana 1872, 363.

321

In Microsyops, six molar teeth immediately succeed the canine in the lower
jaw. In the typical Limnotherium elegans seven molars occupy the same
position. Described page 82, and represented by Figs: 14, 17, Plate VL.

From the Bridger Hocene formation of Wyoming.

MICROSUS.
Microsus CUSPIDATUS.
Leidy: Pr. Ac. Nat. Se. 1870, 113.
See page 81; not positively determined as a distinct species and genus.
Represented by Figs. 10, 11, Plate VI. From the Bridger Eocene
formation of Wyoming.

HIPPOSYUS.
HipPposyus FORMOSUS. )
Leidy: Pr. Ac. Nat. Se. 1872, 37.

Described from a few isolated teeth, page 90, and represented in Fig. 41,
Plate VI, and Figs. 1, 2, Plate XXVII. From the Bridger Eocene of
Wyoming.

HIPPosyUS ROBUSTIOR. r
Notharctus robustior. Leidy: Hayden’s Rep. Geol. Sur. Montana 1872, 364.

Described page 93, and represented by Fig. 40, Plate VI. From the

Bridger Eocene of Wyoming.

HADROHYUS.

HApDROHYUS SUPREMUS.
Leidy: Pr. Ac. Nat. Se. 1871, 248.

Indicated by a mutilated tooth from the Miocene of Oregon. Described
page 222, and represented by Fig. 26, Plate XVII.

PERISSODACTYLA,

Solidungula.
HQuipa.

; EQUUS.

Kquus MAJOR.

Dekay: Nat. Hist. New York, Zool. 1842, 108. Leidy: Ext. Mam. N. America
1869, 399. :

Equus complicatus. Leidy: Pr. Ac. Nat. Se. 1858, 11; Ext. Mam. N. America
1869, 399.

ah G

322

Remains described page 244, and represented by Figs. 3 to 18, Plate
XXXII. From the Quaternary of the United States.

®
JGQUUS OCCIDENTALIS.
Leidy: Pr. Ac. Nat. Se. 1865, 94.
? Hquus. Von Meyer: Palzontographica 1867, 70.
Equus excelsus. Leidy: Pr. Ac. Nat. Sc. 1868, 26; Ext. Mam. Dakota and Ne-
braska 1869, 266, 400, Plate XIX, Fig. 39; XXI, Fig. 31.
Equus pacificus. Deane Pr. Ac. Nat. Se. ‘1868, 195; Ext. Mam. N. America
1869, 400.
Described page 242, and represented by Figs. 1,2, Plate XXXIII. From
the Quaternary ? of Nebraska, Idaho, California, and Mexico.

HIPPARION.
HIPPARION SPECIOSUM ?
Leidy: Pr. Ac. Nat. Sc. 1858, 27; Ext. Mam. N. America 1869, 401.

See pages 247, 248, and Figs. 14,15, Plate XX. From the Tertiary of
Texas.

PROTOHIPPUS, s. MERYCHIPPUS.

PROTOHIPPUS PERDITUS (?) s. MERYCHIPPUS MIRABILIS ?

Protohippus perditus. Leidy: Pr. Ac. Nat. Se. 1858, 26; Ext. Mam. N. America
1869, 401.
Merychippus mirabilis. Leidy: Pr. Ac. Nat. Se. 1858, 27.

See pages 248, 249, 250, and Figs. 16, 20, Plate XX. From the Tertiary
of Texas and Utah.

PROTOHIPPUS PLACIDUS.
Leidy: Ext. Mam. N. America 1869, 401.

See pages 249, 250, and Figs. 17, 18, Plate 2.08 et the Tertiary of
Texas.

ANCHITHERID&.

ANCHITHERIUM.

Meyer: Jahrbuch Mineralogie 1844, 298.

ANCHITHERIUM BatrRDI.

Leidy : Owen’s Rep. Geol. Sur. Wisconsin, &c., 1852, 572; Ext. Mam. N. Amer-
ica 1869, 402; Pr. Ac. Nat. Se. 1870, 112.

323

A full account of the remains of the species from the Mauvaises Terres of
White River, Dakota, is given in the Extinct Mammalia of Dakota and
Nebraska, page 303. A notice of remains from Oregon is given page _

_ 218 of the present work, and a tooth representing the species is given
in Fig. 15, Plate VII. Miocene.
ANCHITHERIUM Conponi.
Leidy: Pr. Ac. Nat. Se. 1870, 112.

Described page 218, and represented by Fig. 5, Platé Ii. From the

Miocene of Oregon.
ANCHITHERIUM AGRESTE.
Anchitherium. WLeidy: Pr. Ac. Nat. Se. 1871, 199.

Described page 251, and represented by Figs. 16,17, Plate VIL From
the Miocene ? of Montana.

. Ancuiriertum ? AUSTRALE.
Described page 250, and represented by Fig. 19, Plate XX. From the
Tertiary of Texas.

? ANCHITHERIUM.
Hquus. Leidy: Pr. Ac. Nat. Se. 1868, 195.

Hquus parvulus. Marsh: Am. Jour. Se. 1868.
Noticed page 252, and represented by Fig. 23, Plate XX. From the
Tertiary of Nebraska.

PALASOSYOPS.

Leidy: Pr. Ac. Nat. Se. 1870, 113; 1871, 114, 118, 197, 229; 1872, 168, 241.
Hayden’s Prelim. Rep. Geol. Sur. Wyoming 1871, 355. Hayden’s Prelim. Rep.
Geol. Sur. Montana 1872, 358, published April, 1772.’
Telmatherium. Marsh: Am. Jour, Se. 1872, IV, 123, published in advance July
22, 1872.
Limnohyus. Marsh: Am. Jour. Se. 1872, IV, 124, published in advance July 22,
1872. Cope: Pr. Am. Phil. Soe. 1873. 5
Remains referable to the genus Palzeosyops are the most common of those
of the larger extinct mammals cccurring in the Bridger Eocene formation
of Wyoming. The, genus was originally indicated by characteristic spec-
_imens of teeth represented in Figs. 4, 5, Plate V, and Figs. 3 to 6, Plate
XXII. Subsequently a number of specimens were received from time
to time and indicated in the Proceedings of the Academy from 1870 to
1872, and in Professor Hayden’s Preliminary Report of the Geological Sur-

324

veys of Wyoming and Montana. In the report oi Montana, published in
April, 1872, the characters of the genus are succinctly stated. Palao-
syops is described ‘as an odd-toed pachyderm, with the skeleton con-
structed nearly as in the tapir. The thigh-bone possesses a third tro-
chanter. The hind feet nearly repeat the construction of those of the
tapir. The skull, with its large temporal fosse, high and thick sagittal
crest, concave occiput, broad, convex face, resembled that of the related
Paleotherium. ‘The teeth also agree in number and nearly in constitu-
tion with those of that animal. The number of teeth altogether appear
to have been 44, consisting of 3 incisors, 1 canine, 4 premolars, and 3
molars to the series on each side, above and below. The teeth in each
jaw form a nearly unbroken arch, intervals existing only sufficient to
accommodate the passing of the points of the large and bear-like canines.

“The true molars have a resemblance to those of Paleeotherium. In the
crowns of the upper true molars the inner constituent lobes are
more completely isolated from the outer ones than in that genus, and the
bottoms of the transverse valleys are proportionately of less depth. The
last upper molar of Paleosyops has but a single lobe to the inner part of
the crown. . 7

“In Paleotherium, the large premolars have the same form as the true
mo! out are quite different in this respect in Paleosyops. In the
former the crown of the upper premolars, except the first, is composed
of four lobes, as in the succeeding molars. In Palzosyops the first pre-
molar has a conical crown, the second a bilobed crown, and the third
and fourth have trilobed crowns.

“'The canines of Palzeosyops are proportionately as large and of the same
form as in the bears”

In an article in the American Journal of Science, 1872, V, published in
advance July 22, 1872, Professor Marsh, after remarking that the type
of the genus Palewosyops is too imperfectly known to determine its more
important characters, adds that, “in some specimens which agree best
with the original description of paludosus, the last upper molar has two
inner cones, and to this group the name Paleosyops may in future be
restricted. The other specimens have but a single internal cone on the
last upper molar, and for the genus thus represented the name Limno-

hyus is proposed.”

325

In this view Professor Cope has recently described some remains of Palz-
osyops under the name of Limnohyus levidens.

Teeth such as I have attributed to Palzeosyops are comparatively abundant,
but I have not yet had the opportunity of inspecting a specimen of a
last upper molar, such as Professor Marsh ascribes to Paleeosyops, in
which the inner side of the crown possesses two internal cones. That
such exist there can be no question, as proved by Professor Marsh’s
description of Palgosyops laticeps. .

Professor Marsh has described some remains which he refers to a genus
with the name of Telmatherium. Of this, he observes: “The dentition
of th's genus, so far as is known, appears to be similar to that of Paleo-
syops. ‘he upper molar teeth have the inner cones more elevated and
more pointed than in Palzosyops, and the.basal ridge is well developed
The last upper molar has but a single internal cone.” He also remarks
that “the two may be readily distinguished by the anterior portion of the
skull, which in Telmatherium has the premaxillaries compressed, with an
elongated median suture. The zygomatic arch is also much less strongly
developed, and the squamosal portion of it is comparatively slender.” Sach
differences are more likely to be of a sexual or individual character than of
either specific or generic value.

- Since writing the preceding chapters we have attempted to give a restora-
tion of the skull of Palewosyops in Fig. 1, Plate XXXI, built up from a
number of specimens. The cranium and face were mainly reconstructed
from the specimens of Fig. 51, Plate XVIII, and Figs. 1, 2, Plate XXIV;
the lower jaw from the specimen of Fig. 52, of the latter plate, and Fig.

5
4, of the former plate.

1. PaLzosyors PALUDOSUS.
Leidy: Pr. Ac. Nat. Se. 1870, 113; -1871, 114, 197, 229; 1872, 168; Hayden’s
Rep. U. S. Geol. Sur. Wyoming 1871, 355; Hayden’s Rep. U. S. Geol. Sur.
Montana 1872, 359. |
Palcosyops. Leidy: Pr. Ac. Nat. Se. 1871, 118.
Limnohyus levidens. Cope: Pr. Am. Phil. Soc. 1873, article published in advance
January 31, 1873.

The description of the species is given on page 28 of the present work.
The specimens represented in Figs. 1 to 8, Plate IV; Figs. 4 to 11,
Plate V; Figs. 1 to 4, Plate XIX; Figs. ] to 7, Plate XX; Figs. 3 to

326

6, Plate XXIII; Figs. 6, 7, Plate XXIV; and Fig. 5, Plate X XIX, are
considered as pertaining to Palcosyops paludosus.

A fine specimen, consisting of the greater part of a skull, exhibited by

Professor Cope to the Academy, and described by him under the name

of Limnohyus laevidens, appeared to me to be the same as Paleosyops

paludosus. From the Bridger Eocene formation of Wyoming.

2. PALMOSYOPS MAJOR.:
Leidy: Hayden’s. Prelim. Rep. Geol. Sur. Montana, April, 1872, 359; Pr. Ac.
Nat. Se. 1872, 168, 241.
Lymnohyus robustus. Marsh: Am. Jour. Se. 1872, [V, 124, published in advance .
July 22, 1872.

I am not convinced that this is a really distinct species from Paleosyops
paludosus. A large number of specimens referable to the genus would
indicate a considerable variation in the size of individuals, of which the
more robust forms may have been males. ‘The species is described on
page 45. The specimens regarded as_pertaining to it are represented
in Fig. 8, Plate XX; Figs. 1,2, 7 to 12, 14 to 16, Plate XOX y gamed
Figs. 1 to 5, Plate XXIV. From the Bridger Eocene formation of
Wyoming.

- 3. PALAOSYOPS HUMILIS.
Leidy: Pr. Ac. Nat. Se. 1872, 168, 277.

Probably a small species indicated by an upper molar, represented in Fig.
8, Plate XXIV, and noticed page 58. From the Bridger. Eocene of
Wyoming.

4. PALHOSYOPS JUNIUS.
Paleosyops junior. Leidy: Pr. Ac. Nat. Se. 1872, 277.

Described page 57. From the Bridger Eocene of Wyoming.

LIMNOHYUS.

LIMNOHYUS LATICEPS.
Palcosyops laticeps. Marsh: Am. Jour. Se. 1872, 122.
‘Indicated page 58, and represented by Fig. 13, Plate XXIII. . From the —
Bridger Kocene of Wyoming.

B27

HYRACHYUS.

TyRacilyUS AGRARIUS.
Leidy: Hayden’s Prelim. Rep. Geol. Sur. Wyoming 1871, 357; Pr. Ac. Nat. Se.
1871, 229; 1872, 19, 168; Hayden’s Rep. Geol. Sur. Montana 1872, 361.
Hyrachyus agrestis. Weidy: Hayden’s Rep. Geol. Sur. Wyoming 1871, 357.
Lophiodon Bairdianus. Marsh: Am. Jour. Se. 1871, IT, 3.

The species is described page 60 of the present work, and specimens
attributed to it are represented in Figs. 11, 12,-Plate IL; Figs. 9 to 18,
Plate IV; and Figs. 25, 26, Plate XX. From the Bridger Eocene of
Wyoming.

HyRACHYUS EXIMIUS. kg
Leidy: Pr. Ac. Nat. Se. 1871, 229; 1872, 168; Hayden’s Rep. Geol. Sur. Mon-
tana 1872, 361.

Described page 66, and represented by Figs. 19, 20, Plate IV; Fig. 5,
Plate XIX; and Figs. 9, 10, Plate XXVI. From the Bridger Eocene
of Wyoming. ;

HyRACHYUS MODESTUS.
Leidy: Pr. Ac. Nat. Se. 1872, 20; Hayden’s Rep. Geol. Sur. Montana 1872, 361.
Lopliodon modestus. Leidy: Pr. Ac. Nat. Se. 1870, 109. :
Described page 67, and represented by Fig. 13, Plate Il. From the
Bridger Eocene of Wyoming.
HyRAcHYUS NANUS. |

Leidy: Pr. Ac. Nat. Se. 1872, 20; Hayden’s Rep. Geol. Sur. Montana 1872, 361:
? Lophiodon nanus. Marsh: Am. Jour. Se. 1871, II, 37.

Described page 67, and represented by Fig. 14, Plate II; Fig. 42, Plate
Vi; Fig. 11, Plate XXVI; and Figs. 21, 22, Plate XXVIII. From
the Bridger Eocene of Wyoming.

LOPHIODON ?

LopHiopoN OCCIDENTALIS.
Leidy: Pr. Ac. Nat. Se. 1868, 232; Ext. Mam. N. America 1869, 391.

Noticed as probably found in the Miocene of Oregon, page 218, and repre-
sented in Fig. 1, Plate II.

LOPHIOTHERIUM.

LGPHIOTHERIUM SYLVATICUM.
- Leidy: Pr. Ac. Nat. Se. 1870, 126.

328
Described page 69, and represented by Figs. 33 to 35, Plate VI. From
the Bridger Eocene of Wyoming.

RHINOCEROTIDA.

RHINOCEROS. -
RHINOCEROS PACIFICUS.
Leidy: Pr. Ac. Nat. Se. 1871, 248. °
Rhinoceros occidentalis. Leidy: Pr. Ac. Nat. Se. 1870, 112.
Described from teeth on page 221, and represented by Figs. 6, 7, Plate
II, and Figs. 24, 25, Plate VIL. From the Miocene of Oregon.

RHINOGEROS HESPERIUS ?
Leidy: Pr. Ac. Nat. Se. 1865, 176; 1870,112; Ext. Mam. N. America, 1869, 390.

Originally described from the ramus of a lower jaw from the Miocene? of
California. Also supposed to be indicated by teeth described page 220,
and represented by Figs. 8, 9, Plate II, from the Miocene of Oregon. ,
In the May number of the American Journal of Science for 1873, Professor
Marsh has noticed remains of rhinoceros, which he refers to two addi-
tional species. One named J?. annectens is founded on remains from the
same formation as those of the preceding species. The other, named-

R. oregonensis, is reputed to have pertained to the ee deposits of
Oregon.

FAMILIES UNDETERMINED.

ANCHIPPODUS.

ANCHIPPODUS RIPARIUS.

Leidy: Pr. Ac. Nat. Se. 1868, 232 ; Ext. Mam. N. America, in Jour. Ac. Nat. Se.
1869, VII, 403, Figs. 45, 4G, Plate XXX.

Paes yops minor. Marsh: ke. Jour. Se. 1871, Ii, 36. ,

Trogosus castoridens. Leidy: Pr. Ac. Nat. Se. 1871, 118; Hayden’s Rep. Geol.

Sur. Montana 1872, 360.
Described page 71, under the name of Trogosus castoridens, and.also repre-
sented as such in Figs. 1 to 3, Plate V.
The genus Anchippodus was originally named from an isolated tooth from
a Tertiary formation of Monmouth County, New Jersey. The speci-
men is represented in Figs. 45, 46, Plate XXX, of the seventh volume
of the Journal of the Academy for 1869, and is described on page 403
of that work. It was not until after the description of the lower jaw

329

referred to Trogosus castoridens, or page 71 of the present work, and
represented under the same name in Figs. 1 to 3, Plate V, that I noticed
the identity in character of the corresponding tooth. Previous to the
description of the jaw referred to Trogosus, Professor Marsh had pub-
lished a notice of a similar tooth under the name of Paleosyops minor.

It is not improbable, after all, that Trogosus may be distinct from Anchip-
‘podus, for there are several genera which, while they have the inferior
true molars alike, have the premolars and upper true molars quite differ-
ent. While regarding Trogosus the same as Anchippodus, for the same
reason I have considered Trogosus castoridens the same as Anchippodus
riparius, for the specimen upon which the latter was originally made known
is identical in form and size with the corresponding tooth in the jaw of
the former. Nor is it improbable that they are the same, for they were
probably of contemporaneous age, and perhaps extended throughout the
continent, as the American, mastodon did at a later period. Specimen
from the Bridger Hocene of Wyoming. .
ANCHIPPODUS VETULUS.

Trogosus vetulus. Leidy: Pr. Ac. Nat. Se. 1871, 229; Hayden’s Rep. Geol. Sur.
Montana 1872, 360.
Noticed on page 75, under the name of Tyrogosus vetulus, and represented,
with the name of Anchippodus vetulus, in Vig. 43, Plate VI. From the
Bridger Kocene of Wyoming.

NOTHARCTUS.

NoOTHARCTUS TENEBROSUS.
Leidy: Pr. Ac. Nat. Se. 1870, 114. —

Described page 86, and represented by Figs. 36, 37, Plate VI. From the
Bridger Eocene of Wyoming.

Proboscidea.
ELEPHAS.

IXLEPHAS AMERICANUS.
Dekay: Nat. Hist. New York, Zool., 1842, 1,101. Leidy: Ext. Mam. N. America
1869, 398.
Hlephas Columbi. Falconer: Quart. Jour. Geol. Soc. 1857, 319, &e.:
Hlephas Texianus. Owen: Rep. Brit. Asso. 1858, 84, &e.
Hlephas imperator. Leidy: Pr. Ac. Nat. Sc. 1858, 10.
42 G

330

Euelephas Jacksoni. Briggs and Foster: Canad. Nat. and Geol. 1865, 135, 147.
BHuelephas Columbi. Falconer: Palaont. Mem. 1868, II, 211 to 234.
ilephas. Von Meyer: Palsontographica, 1867, 70, Plate VII, Figs. 7, 8.

See page 238. Remains noticed from New Mexico and Texas.

MASTODON.

Mastropon AMERICANUS.

Leidy: Pr. Ac. Nat. Sc. 1868, 175. For synonymy, see Extinct Mammalia of
North America 1869, 392.

Some remains described or noticed page 237, and represented in Figs. 5,
6, Plate XXII, and Fig. 9, Plate XXVIII. ;

Remains of the common American mastodon are found in the Quaternary
formation throughout the United States.

MASTODON MIRIFICUS.

Leidy: Pr. Ac. Nat. Se. 1858, 10; 1870, 67; Ext. Mam. Fauna of Dakota and
Nebraska 1869, 249, 396. ;
Mastodon (Tetralophodon) mirificus. Leidy: Pr. Ac. Nat. Se. 1858, 10.-

Remains originally described from the Pliocene of the Loup Fork of Platte
River. Also reported to occur on the Niobrara River, Nebraska. No-
ticed page 237. From the Pliocene of Sinker Creek, Idaho.

MastToDoN OBSCURUS.
Leidy: Ext. Mam. N. America 1869, 396. For earlier synonymy, see the same

work. Pr. Ac. Nat. Sc. 1870, 99; 1871, 199; 1872, 142.
Mastodon Shepardi. Leidy: Pr. Ac. Nat. Se. 1870, 98; 1871, 199.
Rhynchotherium ? See Falconer: Paleontological Memoirs, 1868, II, 74.

Originally named from remains found in Maryland, North Carolina, and

Georgia. See Extinct Mammalian Fauna of Dakota and Nebraska,
1869, 244, 396. Remains from California and New Mexico described
page 231 and represented in Figs. 1 to 4, Plate XXI and Figs. 1 to 4,
Plate XXII, of the present work, are supposed in whole or part to
belong to the same species. If they do not, they would represent
another species, which might retain the name of MW. Shepard.

In the Paleontographica for 1867, page 64, Von Meyer has given a
description of the right ramus of the lower jaw of a Mastodon, from
Mechoacan, Mexico. The specimen is represented in Plate VI of the
same work, and it contains the last molar and the one in advance,
both entire. The portion of the last molar tooth in the jaw-fragment

3 331
from New Mexico, described page 235, and represented in Figs. 1, 4,
Plate XXII, bears a very near resemblance with the corresponding —
part of the same tooth in the Mechoacan specimen. Notwithstanding
this likeness, it would appear that the fore part ofthe jaw differs so
‘much that. the two may be supposed not to pertain to the same species.
As stated in the account of the New Mexico Mastodon, the anterior
extremity of the jaw is enormously prolonged and provided with a pair
of incisors. Von Meyer observes of the Mechoacan specimen, “Too
little of the symphysis is preserved to speak with any certainty of its
constitution; but it appears not to have contained incisors and rather
ended in front ‘in a short beak, as in the elephant.” The jaw he refers
with doubt to the Mastodon Humboldti.

I have said that the New Mexican and Mechoacan specimens may be
supposed not to pertain to the same species. However, when we con-
sider the difference in the fore part of the lower jaw of the sexes in
the Mastodon americanus, it is not improbable that the male of the
Mastodon Shepardi may have had the lower jaw provided with a long
beak and incisors which might have been absent in the female.

UINTATHERIUM.

Titanotherium. Marsh: Am. Jour. Se. 1871, II, 35; the- article published in
advance June 21, 1871; ibid. 1872, IV, 123, published in advance July 22,
1872. ‘ ’

Mastodon. Marsh: Am. Jour. Se. 1872, note to p. 123, published in advance
July 22, 1872. ‘

UINTATHERIUM.

Leidy: Pr. Ac. Nat. Se. 1872, 169; in a letter addressed to the Academy and
published in advance of the proceedings August 1, 1872. Reprinted in Am.
Jour. Se. September, 1872, 239. Pr. Ac. Nat. Se. 1872, 241. Marsh: Pr. Am.
Phil. Soc. 1872, 578; Am. Jour. Se. 1873, V, 118; American Naturalist
1873, 147. Cope: Pr. Ac. Nat. Se. 1873,10, 102; Pr. Am. Phil. Soc. Feb.,
1873. Nature: March 13, 1873, 366,

Uintamastix. Leidy: Pr. Ac. Nat. Se. 1872, 169.

Tinoceras. Marsh: Am. Jour. Se. 1872, IV, in errata.of Sept. No.; do., p. 504,
published in advance August 19, 1872; ibid. 1872, IV, 322, published in
advance August 24, 1872; ibid. 1872, 1V, 323. published in advance Sep-
tember 21, 1872; «bid. 1872, IV, 343, published in advance September 27,
1872; ibid. 1873, V, 117, published in advance January 28, 1873; ibid, 1873,
V, 293, published in advance March 18, 1873; American Naturalist Jan.,
1873, 52.

Hobasileus. Cope:* Pr. Am. Phil. Soe. 1872, 485, published in advance August
20, 1872; ibid. 1872, 542; ibid. 1873, published as a separate pamphlet, “On
the Short-Footed Ungulata of the Eocene of Wyoming,” March 14, 1873; Pr.
Ac. Nat. Se. 1873, 10, 102; American Naturalist, March 1873, 180.

Loxolophodon. Cope: Pr. Am. Phil. Soe. 1872, 487, 488, published in advance
August 22,1872. Here regarded as the same genus first named in the Pro-.
ceedings of Iebruary 16, 1872, 420, and founded on the tooth of an animal
about the size of the American tapir, referred to Bathmodon semicinctus and
then to Loxolophodon. Pr. Am. Phil. Soc. 1872, 580; Pr. Ac. Nat. Se. 1873,
102.

Lefalophodon. Typographical error? Cope: Pr. Am. Phil. Soc. 1872, 515.

Dinoceras. Marsh: Am. Jour. Se. 1872, IV, 344, published in advance September
27, 1872; ibid. 1873, V, 117-122, Plates I, II, published in advance January
28, 1873; ibid. April, 1873, published in advance March 18, 1873; American
Naturalist, March 1873, 146. Nature, March 13, 1873, 366.

Loxolophodon. Cope: “On the Short-Footed Ungulata of the Eocene of
Wyoming,” read before the Am. Phil. Soc., Feb. 21, 1873, and published in
advance of the Proceedings, March 14, 1873. The name is here used as that
of a genus recognized as distinct from the one originally described under the
same name, which the author now regards as a synonym of Bathmodon.

All the above names I suspect to have been applied to members of the
same genus, and in this view have regarded them as synonyms to. the
first characteristic generic name employed. Of this, however, I am by
no means positive, as I have had no opportunity of examining the
different fossils upon which the genera were founded, except those.
described by myself under the name of Uintatherium robustum, and the
skull described by Professor Cope under the name of Loxolophodon cornutus.

In addition, we have the description and figures of the skull described by
Professor Marsh under the name of Dinoceras mirabilis.

As far as I am able to estimate the differences which have been indicated
* by the authors just named and those observed by myself, they appear to be
rather .of specific value, and perhaps in part of sexual character, than of
generic importance. We hope, however, that all obscurity in relation to the

matter will be cleared away when Professor Marsh and Professor Cope
"present to us full descriptions with characteristic figures of the fossils in.
their possession. I may add it is not improbable that the names of
Uintatherium, Tinoceras, Eobasileus, Dinoceras, and Loxolophodon, may be

*The dates given as those of Professor Cope’s publications in advanee of the dif- »
ferent periodicals named are taken from the publications themselves; but they are,
in some instances, contested by Professor Marsh. See an article read before the
Philadelphia Academy of Sciences April 8, 1873, and published by Professor Marsh
under the title ““On the Dates of Professor Cope’s Recent Publications.”

333

expressive of more than one genus, in the light that Cariacus, Capreolus,
Blastocerus, Axis, Elaphus, &c., are distinct from Cervus. Future compari-
sons and discoveries will perhaps reduce the nine species of the five genera
which have been indicated to the number of two or three species of one or
two genera. .

Professor Marsh has referred the remarkable animals above indicated to a
new order with the name Dinocerata. In the uncertainty as to the true
ordinal position of Uintatherium, I have ailowed it to remain, according to
my first impression, with the Proboscidea.

UINTATHERIUM ROBUSTUM.

Leidy: Pr. Ac. Nat. Sc. 1872, 169, in a letter addressed to the Academy and
published in advance of the proceedings, August 1, 1872. Reprint of the
letter in Am. Jour. Sc. September, 1872, 239. Pr. Ac. Nat. Se. 1872, 241.
Cope: Pr. Ac. Nat. Se. 1873, 102; Pr. Am. Phil. Soc. 1873. Marsh: Am.
Jour. Se. 1873, V, 296; American Naturalist, January, 1873.

Uintamastix atrox. Leidy: Pr. Ac. Nat. Se. 1872, 169; Am. Jour. Se. 1872, 239.
Dinoceras mirabilis. Marsh: Am. Jour. Se. 1872, IV, 344, published in advance

September 27, 1872; ibid. 1873, V, 117-122, Plates I, I], published in advance
January 28, 1873; Ibid. April, 1873, published in advance March 18, 1873.
American Naturalist, March, 1873, 146. Nature, March 13, 1873, 366.
Uintatherium miradile. Cope: Pr. Ac. Nat. Se. 1873, 102; Pr. Am. Phil. Soe.
> 1873, published in advance “ On the Short-Footed Ungulata of the Eocene of
Wyoming, March 14, 1873, 28.”

The Figs. 6 to 12, Plate XXV, Figs. 1 to 3, Plate XX VI, and Figs. 30 to 34.
Plate XX VII, of the present work, represent the chief type-specimens upon
which the genus Uintatherium was founded and the species U. robustum
named. Descriptions of these occur on pages 93 and 96.

The large canine tooth represented in Figs. 1 to 5, Plate XXV, was, on
discovery, supposed to belong to a Drepanodon-like carnivore. The dis-
covery of the nearly complete skulls described by Professor Marsh under the
name of Dinoceras mirabilis, and Professor Cope under the name of Lozolo-
phodon cornutus, leaves no doubt that the remarkable tooth belongs to the
same kind of an animal, which, from the proportions of the specimen, I sup-
pose to be Urntatherium robustum.

The fine skull discovered and described by Professor Cope under the name
of Loxolophodon cornutus, 1 had the opportunity of seeing on the occasion
when it was exhibited at.a meeting of the Academy of Natural Sciences.
So far as I could judge from the cursory examination, and from the more

304

recent description and figures of the skull, it appears to me to be a larger
species of Uintatherium than the U. robustum, but not of a distinct genus.

The remains, which were first noticed by Professor Marsh and referred to
Titanotherium (2) anceps, subsequently to Mastodon anceps, and finally to
Tinoceras anceps, I have not seen. I have suspected that perhaps they
might pertain to the same animal as that I have described as Uintatherium
robustum. Should this prove to be the case, as the specific name of anceps
is of earliest date, the latter would be correctly designated as Uintatherium
anceps.

Professor Marsh regards the Kobasileus s. Loxolophodon cornutus, Cope, as
pertaining to Tinoceras, probably T. grandis, Marsh, (Am. Jour. Se. April,
1873.) On the other hand Professor Cope refers Dinoceras to Uintatherium,
and also includes as synonyms Titanotherium (2) anceps, and therefore Tinoceras,
Marsh, (Pr. Am. Phil. Soc. 1873.) Thus the conjoint views of these authors
rather favor the idea that all are probably of the same genus.

Since the article’ on Uintatherium robustum, page 96, was printed, I have
attempted a restoration of the skull in Fig. 1, Plate XXVIII, on an enlarged
outline taken from Professor Marsh’s Fig. 1, Plate II, of Dinoceras mirabilis,
published in the American Journal of Science for February, 1873. The
cranial fragment and that of the upper jaw with the last molar tooth are
taken from the same skull as the specimens of Fig. 8, Plate XXYV, and |
Fig. 1, Plate XXVI. The canine is from the same specimen as Fig. 1, Plate
XXYV.

In the May number of the American Journal of Science for 1873, Pro-
fessor Marsh has indicated what he considers to be a new species of Dinoceras
with the name of D. ducaris: In the account he observes, “ From Uintatherium,
so far as that genus is at present known, Dinoceras differs in the position of
the occipital condyles, in the more anterior position of the posterior horns,
and in the last molar, which lacks the external cone between the two trans-
verse ridges, and has a second small tubercle behind the posterior ridge.”
These characters may, perhaps, together with others more important, point
to a different species, but appear hardly sufficient to distinguish a genus.
The differences are also more apparent than real; for instance, the so-called
“external cone between the two transverse ridges” of the last molar, as seen
in Fig. 7, Plate XXV, is nothing more than a tubercle preduced from the
basal ridge, might be absent in another individual, and is actually so in the

molar in advance, as seen in Fig. 12 of the same Plate.

335

MEGACEROPS® s. Megaceratops.

MEGACEROPS COLORADENSIS. |
Leidy: Pr. Ac. Nat. Se. 1870, 1; Hayden’s Rep. Geol. Sur. Wyoming, 1871, 352.
Megaceratops coloradoensis. Cope: Pr. Ac. Nat. Se. 1873, 102; Pr. Am. Phil.
Soe. 1873. ;
Described page 239, and represented by Figs. 2, 3, Plate I, and Fig. 2,
Plate II.

Before the discovery of the more characteristic specimens of the skulls of
species of Uintatherium, from the nearer resemblance of the fossil described
under the name of Megacerops to the corresponding part of Sivatherium,
the animal to which it belonged was supposed to be a ruminant. It now
appears probable that Megacerops forms a member of the same order, what-

ever that may be, with Uintatherium.
Rodentia.
: Scrurip&.

PARAMYS.
_PARAMYS DELICATUS. :
Leidy: Pr. Ac. Nat. Se. 1871, 231; Hayden’s Rep. Geol. Sur. Montana, 1872,
307. j
Described page 110, and represented by Figs. 23 to 25, Plate VI. From
the Bridger Eocene of Wyoming.
PARAMYS DELICATIOR. .
Leidy: Pr. Ac. Nat. Se. 1871, 231; Hayden’s Rep. Geol. Sur. Montana, 1872, 357.
Described page 110, and represented by Figs. 26, 27, Plate VI, and Figs.
16 to 18, Plate XXVII. From the Bridger Eocene of Wyoming.
PARAMYS DELICATISSIMUS.
Leidy: Pr. Ac. Nat. Se. 1871, 231; Hayden’s Rep. Geol. Sur. Montana, 1872, 357..
Described page 111, and represented by Figs. 28, 29, Plate VI. From
the Bridger Eocene of Wyoming.

SCIURAVUS? :
Marsh: Am. Jour. Se. 1871, 122.
A tooth supposed to pertain to this genus is described on page 113, and
represented in Fig. 30, Plate VI. From the Bridger Eocene of Wyo-

ming.

* For the sake of both brevity and euphony, I have preferred to use Megacerops
instead of Megaceratops, just as Megatherium is preferred to Megalotherium, &e.

336
Murip4. (1)

MYSOPS.

MyYSoPS MINIMUS.

Leidy: Pr. Ac. Nat. Se. 1871, 232; Hayden’s Rep. Geol. Sur. Montana, 1872,
357.

Described page 111, and represented by Figs. 31, 32, Plate VI. From the
_ Bridger Eocene of Wyoming.
Mysors FRATERNUS.
Described page 112, and represented by Figs. 14, 15, Plate XXVIL
From the Bridger Eocene of Wyoming. c

Insectivora.
FAMILIES UNDETERMINED.

OMOMYS.
OMOMYS CARTERI.
Leidy: Pr. Ac. Nat. Se. 1869, 63.

Originally described in the Extinct Mammalia of North America, 1869,
408, and represented in Figs. 13, 14, Plate X XIX of the same work.
Redescribed in the present work, 120. From the Bridger Eocene of
Wyoming.

PALAZACODON.
PALZACODON VERUS.
Leidy: Pr. Ac. Nat. Se. 1872, 21; Hayden’s Rep. Geol. Sur. Montana, 1872, 356.
Described from specimens of teeth page 122, and represented by Fig. 46,
Plate VI. From the Bridger Eocene of Wyoming. “

WASHAKIUS.
W ASHAKIUS INSIGNIS. phone
Described ‘page 123 from a small jaw-fragment ‘containing the last two
molars, and represented in Figs. 3, 4, Plate XX VII. From the Bridger
Hocene of Wyoming.

Sirenia.
MANATUS.

MANATUS INORNATUS.
Figs. 16,17, Plate XX XVII, represent the crown of a tooth from the
‘“phosphate beds” of the Ashley River, South Carolina. It most nearly

337

resembles the corresponding part of the lower teeth of the living Manatee of
the Florida coast, and it indicates an animal of about the same size. The
constituent lobes of the crown are less contracted approaching the summits,
and the intervening valleys are wider than in the teeth of the living Manatee.
The summits of the lobes being less contracted, are also sharper and not so
wrinkled. The summit of the anterior lobe presents a wider and deeper
oval pit, and the posterior heel is less mammillary, not wrinkled at the sum-
mit, and is broadly sloping at its fore part. The crown measures half an inch
four and aft and 44 lines where widest.

Zeuglodontia.

PONTOBASILEUS. |

PONTOBASILEUS TUBERCULATUS.

Fig. 15, Plate XXXVII, represents a fragment of a remarkable tooth,
apparently belonging to an animal of the same order as the Basilosaurus.
The specimen pertains to the Museum of the Academy of Natural Scierices
of Philadelphia. Itis without label, and was associated with some Basilosaurus
remains from Alabama. I suppose it to have been derived from some Eocene
or Miocene formation of the Atlantic States. Upon the fang there are the
remains of two white disks, apparently the basal attachment of barnacles.

The fragment consists of the back portion of the crown and the corre-
sponding fang of a double-fanged tooth. The crown has been very unlike
that of any known animal of the order. The conical summit occupied a
position over the separation of the fangs, including at most the anterior one.
The back part of the crown forms a wide, thick heel, extending over more
than half the width of the corresponding fang. The enamel is exceedingly
tuberculate, and near the most prominent portion of the heel outwardly it is
worn off over a small oval space from attrition of an opposed tooth. The
fang is widely divergent, and is depressed along the middle externally and
internally, and also more deeply on the surface opposed to the absent fang.

Cetacea.
DeLPHINIpaé.
GRAPHIODON.
GRAPHIODON VINEARIUS.
Leidy: Pr. Ac. Nat. Se. 1870, 122.
An extinct genus and species of cetacean animals, apparently different
43 G

338

from any previously described, is indicated by a fossil submitted to my
examination by the Smithsonian Institution. The specimen was found by
Mr. Pearce in the Miocene formation of Gay Head, Martha’s Vineyard. It
consists of a tooth represented in Fig. 7, Plate XXII, of the natural size.

The form of the tooth, with its huge gibbous fang, led me at first to mis-
take it for that of a mosasauroid reptile, nor did I observe my error until it
was suggested by Professor Marsh

The crown of the tooth is curved, conical, and without subdivisional planes
upon the surface. ‘The inner and outer surfaces are barely defined postero-
internally by a feeble and interrupted ridge. The enamel is singularly
wrinkled, the wrinkles being short, vermicular, somewhat branched and
crowded, and they remind one of Arabic letters. At the base of the crown
the enamel is nearly smooth. The transverse section of the crown is cir-
cular, and measures 8 lines in diameter. The length of the crown when
complete appears to have been about twice the latter.

The fang of the tooth, broken at the extremity, exposes to view a large
interior pulp cavity. It is longer than the crown and very gibbous. In its
relation of size and form, it is wonderfully like the corresponding part in the
teeth of Mosasaurus. It is ovoidal in form and is curved in the direction of
the crown. It is abruptly thickened at the base of the latter, and on one
side, near the extremity, exhibits a deep groove. The texture of the fang, as
seen at its broken part, appears as dense as ordinary dentine. In the entire
condition, the fang bas approximated 2 inches in length; its diameter is
about half the length.

REPTILIA.

Dinosauria.

POICILOPLEURON.

Deslongchamps: Mem. Soe. Lin. de Normandie VI, 1838, 37.

POICILOPLEURON VALENS.
Leidy: Pr. Ac. Nat. Se. 1870, 3.
Antrodemus. Leidy: Ibidem, 4.

Founded on several fragments of vertebrae described page 267, and rep-
resented by Figs. 16 to 18, Plate XV, under the name of Antrodemus.
From Colorado, and supposed to have been derived from the Cretaceous
formation.

339

Chelonia.
TESTUDINIDA:
TESTUDO.

TrstuDo Corsonl.
Leidy: Pr: Ac. Nat. Se. 1871, 154; 1872, 268; Hayden’s nae Geol. Sur. Mon-
tana, 1872, 366.
Emys Cree. Leidy: Pr. Ac. Nat. Se. 1871, 228; Hayden’s Rep. Geol. Sur.
Montana, 1872, 367.
Described page 132, and represented in Figs. 1, 2, Plate XI, under the
name of Emys Carteri; in Fig. 7, Plate XV; Figs. 2 to 4, Plate XXIX,
and Figs. 1.to 4, Plate XXX. From the Bridger Eocene of Wyoming.

TESTUDO NEBRASCENSIS.

Leidy: Pr. Ac. Nat. Se. 1852, 59; Owen’s Rep. Geol. Sur. Wisconsin, &c. 1852,
567; Ancient Fauna of Nebraska, 1853, 103, Plate XIX; Ext. Mam. Fauna
_ of Dakota and Nebraska, 1869, 26.

Stylemys nebrascensis. Leidy: Pr. Ac. Nat. Sc. 1851, 172; Ancient Fauna of
Nebraska, 1853, 103; Ext. Mam. Fauna of Dakota and Nebraska, 1869, 26.
See page 223. Cope: Ext. Batrachia, &c. 1870, 124.

Emys s. Testudo hemispherica, Oweni, Culbertsoni, et lata. Leidy: Pr. Ac. Nat. Se.
1851, 173, 327; 1852, 34, 59. Owen’s Rep. Geol. Sur. Wisconsin, &c. 1852,
568 to 572; Ancient T'auna of Nebraska, 1853, 105 to 110, Plates XX to
XXIV.

Stylemys Culbertsonii. Cope: Ext. Batrachia, &c. 1870, 124.
Noticed page 224 under the name of Stylemys nebrascensis, and further
represented by Figs..7, 9, 10, Plate XIX.

All the turtle remains from the Mauvaises Terres of White River, Dakota,
which have come under my inspection, and which have been described under
the various names above indicated, I regard as having pertained to a single
species. ‘This agrees so closely in the usual characters of living species of the
land tortoises, that I have placed it in the same genus, though it is subgeneri-
cally distinct. A mature and nearly perfect specimen of the shell in the
Museum of the-Academy of Natural Sciences, obtained by Professor Hayden
in 1866, has the following dimensions:

Inches.
ie Om canna: Il HMETCULY CO. <2 Mre< cine oie cen ae eee eno meen omnes ne 27
Bred onOnm Caray acenn WMO CUEVE. ~ 4+ =< a. cee see asec sews e cine ccise Sere cciciees, soe 26
Vicueitin Gir (OLASIBACTT Se:5 G8 WR OR HAE ee tas OW EGS AAP aera Aisa 20
leneadhh of plastrom 2.2. -4....22..... ARR. Nel ai SRS SE Ae a eee 15

Height of shell above the lev A 5 TN Sel IAS BEES A Ea Ce ec 8

340

TESTUDO NIOBRARENSIS.

Testudo (Stylemys) niobrarensis. Leidy: Pr. Ac. Nat. Se. 1858, 29; Ext. Mam.
Fauna Dakota and Nebraska, 1869, 26. See page 224.
Stylemys niobrarensis. Cope: Ext. Batrachia, &c. 1870, 124.

Described page 225, under the name of Stylemys niobrarensis, and repre-
sented by Figs. 4 to 6, Plate III, and Figs. 6,8, Plate XIX. From the
Pliocene of the Niobrara River.

'TESTUDO OREGONENSIS.
i Stylemys oregonensis. Leidy: Pr. Ac. Nat. Se. 1871, 248. See page 225,
Noticed page 226, under the name of Stylemys oregonensis, and repre-
sented by Fig. 10, Plate XV. From the Miocene of Oregon. I suspect
I have been too hasty in regarding this as a species distinct from Testudo
nebrascensis. )

EMypIp&.
EMYS.

EXMYS WYOMINGENSIS.

Leidy: Pr. Ac. Nat. Se. 1869, 66; Hayden’s Rep. Geol. Sur. Montana, 1872; 367.

Emys Stevensonianus. Leidy: Pr.. Ac. Nat. Se. 1870,5; Hayden’s Rep. Geol.
Sur. Wyoming, 1871, 366.

Emys Jeanesi. Leidy: Pr. Ac. Nat. Se. 1870, 123; Hayden’s Rep. Geol. Sur.
Wyoming, 1871, 366.
Emys Haydeni. Ueidy: Pr. Ac. Nat. Sc. 1870, 123; Hayden’s Rep. Geol. Sur.
_ Wyoming, 1871, 366. 4
The species described page 140, and represented by Figs. 2 to 6, Plate
IX, Figs. 1, 2, Plate X. From the Bridger Eocene of Wyoming.

EMMYS PETROLEL. -
Leidy: Pr. Ac. Nat. Se. 1868, 176. Cope: Ext. Batrachia, &e. 1870, 128.
Species described page 260, and represented by Fig. 7, Plate TX. From:
the Quaternary of Texas.

HYBEMYS.
HyYBEMYS ARENARIUS.
Leidy: Pr. Ac. Nat. Se. 1871, 103.
Noticed page 174, and represented by Fig. 9, Plate XV. From the

Bridger Eocene of Wyoming.

d41

FAMILIES UNDETERMINED, APPARENTLY INTERMEDIATE TO THE PLEURODIRIDZ
AND THE CHELYDRIDZA.

-BAPTEMYS.

BAPTEMYS WYOMINGENSIS.
Leidy: Pr. Ac. Nat. Se. 1870, 4; Hayden’s Rep. Geol. Sur. Wyoming, 1871, 367 ;
Hayden’s Rep. Geol. Sur. Montana, 1872, 367.
Adocus wyomingensis. Cope: Pr. Am. Puil. Soc. 1870, 297; Ext. Batrachia,
Reptilia N. Am. in Trans. Am. Phil. Soc. 1870, 233.

Described page 157, and represented by Figs. 1, 2, Plate XH, and Fig. 6,
Plate XV. From the Bridger Eocene of Wyoming.

CHISTERNON s. Chisternum.
Leidy: Pr. Ac. Nat. Se. 1872, 162.

CHISTERNON UNDATUM.
Baena undata. Leidy: Pr. Ac. Nat. Se. 1871,.228; Hayden’s Rep. Geol. Sur.

Montana, 1871, 369.
Described page 169, and represented by Figs. 1, 2, Plate’ XIV, under the
name of Baena undata. From the Bridger Eocene of Wyoming. |
Chisternon undatum, in the presence of an additional pair of plates to the

plastron, resembles the existing Sternothzerus.
BAENA.
BAENA ARENOSA.
Leidy: Pr. Ac. Nat. Se. 1870, 123; 1871, 228; Hayden’s Rep. Geol. Sur. Wyo- |
ming, 1871, 367 ; Hayden’s Rep. Geol. Sur. Montana, 1872, 368.
Baena afinis. Leidy: Hayden’s Rep. Geol. Sur. Wyoming, 1871, 367.

Species described page 161, and represented by Figs. 1 to 3, Plate XIU,
under the names of Baena arenosa and Baena affinis, Figs. 1 to 5, Plate
XV, and Figs. 8, 9, Plate XVI.

ANOSTEIRA.
ANOSTEIRA ORNATA.
Leidy: Pr. Ac. Nat. Se. 1871, 102, 114; Hayden’s Rep. Geol. Sur. Wyoming, 1872,
370.

Described page 174, and represented by Figs. 1 to 6, Plate XVI.- From

the Bridger Eocene of Wyoming.
'TRIONYCHID&.

TRIONYX.
TRIONYX GUTTATUS.
Leidy: Pr. Ac. Nat. Se. 1869, 66; 1870, 5; 1871, 228; Hayden’s Rep. Geol. Sur.
g Wyoming, 1871, 367; Hayden’s Rep. Geol. Sur. Montana, 1872, 370. Cope:
Ext. Batrachia, &c., t870, 152.

342

Described page 176, and represented by Fig. 1, Plate IX. From the
Bridger Eocene of Wyoming.
TRIONYX UINTAENSIS.
Leidy: Pr. Ac. Nat. Se. 1872, 267.
Described page 178, and eae by Fig. 1, Plate XXIX. From the
Bridger Eocene of Wyoming.

TRON —— ee
Fragments described page 180, and represented in Figs. 11, 12, Plate
XVI. From the Bridger Eocene of Wyoming.

SPHARGIDIDZ!
ATLANTOCHELYS.

ATLANTOCHELYS MORTONI.*

Agassiz: Pr. Ac. Nat. Se. 1849, 169.
Mosasaurus Mitchelli. Leidy: Cret. Rept. in Smith. Contrib. 1865, 43,116. De-
termination admitted by Cope: Pr. Bost. Soc. Nat. Hist. 1869, 253.

Protostega neptunia. Cope: Pr. Am. Phil. Soc. 1872, 433.
Founded on the fragment of a large humerus described in the “ Cretaceous
Reptiles of the United States,” 1865, 43, and represented in Figs. 3, 4,
5, Plate VIII of that work. From the Cretaceous green sand of New
Jersey. See page 270.
ATLANTOCHELYS TUBEROSUS.

Holcodus acutidess. In part of Leidy: Cret. Rept. in Smiths. Contrib. 1865, 42,
118. Determination admitted by Cope: Pr. Bost. Soc. Nat. Hist. 1869, 253.

Platecarpus tympaniticus. In part of Cope: Pr. Bost. Nat. Hist. Soe. 1869, 265 ;
Synop. Ext. Batrachia, Reptilia, &c. 1870, 199.

Protostega. Cope: Pr. Am. Phil. Soe. 1872, 433.

Platecarpus tuberosus. Cope: Pr. Am. Phil. 1872, 433. )

Protostega tuberosa. Cope: Hayden’s Rep. Geol. Sur. Montana, 1872, 330, 334.

Founded on a humerus described in the “Cretaceous Reptiles of the
United States,” 1865, 42, and represented in Figs. 1, 2, Plate VIII of
that work. From the Cretaceous formation near Columbus, Missi ssippl.
See page 270. .

It was the association of this specimen with several cervical vertebra, and

* Professor Cope observes that ‘this name was unaccompanied with the necessary
description, and is hence useless to science.” (Pr. Am. Phil. Soc. 1872, 433.) As the
specimen on which it was fonnded was described and figure. in my paper on the Cre-
taceous Reptiles, so as to be recognized by every student, I have preferred to employ -
the original name instead of the proposed substitute.

343

a palatine bone with teeth of an undoubted mosasauroid, that led me into the
error of supposing it belonged to the same animal. This suggested the idea
that the specimen originally referred to Adtlantochelys Mortoni likewise be-
longed to a Mosasaurus. The error was easy at a time when. the limb-bones
of none of the mosasauroids were known, and when it was even doubted
whether these reptiles possessed hinder limbs. My determination was con-
curred in, not only by Professor Cope, but also by Professor Agassiz, after I
had exhibited to him the different specimens and their associates.* It was
only after I had had the opportunity of seeing the nearly complete fore-limbs
in the skeleton of Clidastes propython, described by Professor Cope, that
I suspected my reference of the specimens of humeri above indicated was
incorrect.

-

CYNOCERCUS?
CYNOCERCUS INCISUS.? .
Cope: Pr. Am. Phil. Soc. 1872, 309.

Remains probably belonging to this species described page 269, and
represented by Figs. 17 to 21, Plate XXXVI. From the Cretaceous
of Kansas.

Mosasauria.
MOSASAURUS?
Mosasaurus —————?

See page 279. Represented by Fig. 15, Plate XXXVI. From the Cre-
taceous of Nebraska.

TYLOSAURUS.

TYLOSAURUS DYSPELOR.
' Marsh: Am. Jour. Se. 1872, 147.
Liodon dyspelor. Cope: Pr. Am. Phil. Soe. 1870, 572, 574; 1571, 169, 280; Hay-
den’s Rep. Geol. Sur. Wyoming, 1871, 410; Hayden’s Rep. Geol. Sur. Montana,
1872, 333.

Rhinosaurus dyspelor. Marsh: Am. Jour. Se. 1872.
Rhamphosaurus. Cope: Pr. Ac. Nat. Se. 1872, 141.
See page 271. Represented by Figs. 1 to 11, Plate XXXV. From the
Cretaceous of New Mexico and Kansas.

*I do not introduce the names of these naturalists as an apology for my error, but
rather to show that able authorities are liable to the same mistakes under the same
circumstances. :

344

TTYLOSAURUS PRORIGER.
Marsh: Am. Jour. Se. 1872, 147.
Macrosaurus proriger. Cope: Pr. Ac. Nat. Se. 1869, 123.
Tiodon proriger. Cope: Trans. Am. Phil. Soc. 1870, 202; 1871, 279; Hayden’s
Rep. Geol. Sur. Wyoming, 1871, 401; Hayden’s Rep. Geol. Sur. Montana, 1872,
333.
Rhinosaurus proriger. Marsh: Am. Jour. Se. 1872.
Rhamphosaurus. Cope: Pr. Ac. Nat. Se. 1872, 141.
See page 274. Represented by Figs. 12, 13, Plate XX XV, and Figs. 1 to
3, Plate XXXVI. From the Cretaceous of Kansas.

LESTOSAURUS.

LESTOSAURUS CORYPHZUS.
Marsh: Am. Jour. Se. 1872. :

Holcodus corypheus. Cope: Pr. Am. Phil. Soc. 1871, 269; Hayden’s Rep. Geol.
Sur. Montana, 1872, 331.

? Platecarpus. Cope: Pr. Ac. Nat. Se. 1872, 141.

See page 276. Represented by Figs. 12 to 14, Plate XXXIV, and Figs.
4 to 14, Plate XXXVI. From the Cretaceous of Kansas.

CLIDASTES.
Cope: Pr. Ac. Nat. Se. 1868, 233.

CLIDASTES INTERMEDIUS.
Leidy: Pr. Ac. Nat. Se. 1870, 4. Cope: Syn. Ext. Batrachia, Reptilia, &e.
1870, 221; Hayden’s Rep. Geol. Sur.. Wyoming, 1871, 412.
Described page 281, and represented by Figs. 1 to 5, Plate XXXIV. From
the Upper Cretaceous of Alabama.
CLIDASTES AFFINIS.
C. intermedius. In part, Leidy: Pr. Ac. Nat. Se. 1870, 4,
Described page 283, and represented by Figs. 6 to 11, Plate XXXIV.
From the Cretaceous of Smoky Hill River, Kansas.

Lacertilia.

SANIWA s. Sanwa.
SANIWA ENSIDENS.
Leidy: Pr. Ac. Nat. Se. 1870, 124; Hayden’s Rep. Geol. Sur. Wyoming, 1871,
368; Hayden’s Rep. Geol. Sur. Montana, 1872, 370.
Described page 181, and represented by Fig. 15, Plate XV, and Fig, 35,
Plate XX VII. From the Bridger Eocene of Wyoming.

d45

SANIWA MAJOR.
Described page 182, and represented by Fig. 14, Plate XV, Figs. 36, 37,
Plate XXVII. From the Bridger Eocene of Wyoming.

CHAMELEO.
CHAMELEO PRISTINUS,

Leidy: Pr. Ac. Nat. Se. 1872, 277.

Described page 184, and represented by Figs, 38, 39, Plate XXVII.
From the Bridger Eocene of Wyoming,

G@LYPTOSAURUS.
Marsh: Am. Jour. Se, 1871; Pr. Ac. Nat. Se. 1871, 105.
‘GLYPTOSAURUS —————?__

Noticed page 182, and represented by Fig. 13 to 17, Plate XVI. From
the Bridger Eocene of Wyoming.

TYLOSTEUS.
TYLOSTEUS ORNATUS.
Leidy: Pr. Ac. Nat. Se. 1872, 40.
Noticed page 285, and represented by Figs. 14, Plate XIX. From the
Upper ae probably Cretaceous.

Saur opter ygia.

NOTHOSAURUS.
NOTHOSAURUS OCCIDUUS.
Nothosaurops occiduus. Leidy: Pr. Ac. Nat. Se. 1870, 74.
Noticed page 287, and represented by Figs. 11 to 13, Plate XV. From
the Cretaceous ? of Moreau River, Dakota.

“OLIGOSIMUS.
OLIGOSIMUS GRANDZVUS.
Leidy: Pr. Ac. Nat. Se. 1872, 39.
Described page 286, and represented by Figs. 18,19, Plate XVI. From
the Cretaceous (?) of Wyoming |
44 6

FISHES.

Teleostet.

LABRID&.

PROTAUTOGA.

PROTAUTOGA CONIDENS. ,
Tautoga (Protuutoga) conidens. Leidy: Pr, Ac. Nat. Se. 1873, 15; Am. Jour. Se.
1873, 312.

A short time since, Mr. C. M. Smith, engineer, of Richmond, Virginia,
submitted to the writer, for examination, a small collection of fossil bones,
which had been discovered by him during the construction of a tunnel
beneath the city. Mr. Smith informs me that the material penetrated by
the tunnel, in which the bones were found, consists of a stiff blue clay con-
taining remains of infusoria. On examining a portion of the substance with
the inicroscope, I observed an abundance of well-preserved frustules of
Coscinodiscus, besides many other less conspicuous diatomes.

The fossil bones consist mainly of vertebrae and teeth of Cetaceans, the
teeth of Procamelus virginiensis, previously described, a portion of a humerus
of a bird, and a number of remains of fishes.

Among the latter there are two specimens which consist of portions of
the premaxillaries, with teeth, represented in Figs. 56, 57, Plate XXXII, of
a species of Tautoga larger than the living black-fish, Tautoga americana.

The better-preserved specimen exhibits the base of attachment of the
first large tooth, and succeeding it a row of seven teeth. ‘These are separated
by wider intervals than the fewer teeth of the same kind of the recent black-
fish. The points of the teeth are more regularly conical than in the latter.
Within the position of the larger teeth there is a row of small teeth.

The second specimen contains the first large tooth alone. This tooth is
not longer than in the recent black-fish, but is more robust, and its enameloid-
covered extremity is more perfectly conical or is less flattened from without
inwardly.

The premaxillary bone is flatter externally than in the black-fish, and looks
as if it had not turned down in a hook-like end as in the latter. The speci-

347

mens I have supposed to indicate a genus closely related with Tautoga, and
have named it Protautoga.

The more complete specimen contained a row of eight teeth in a space of
an inch and a quarter from the symphysis. The first large tooth is 53 lines
long; the crown-like portion is 34 lines long, with the breadth at base 24
lines. The second tooth is 4.4 lines long; the crown-like portion is 2 lines
long and 1.6 lines in diameter at base. The other teeth range from 2 lines
to a line in length.

SPHYRANIDZ.

ENCHODUS.

Encropus SHumarp1.
Leidy: Pr. Ac. Nat. Se. 1856, 257.
. Described page 289, and represented by Fig. 20, Plate XVII. From the

Cretaceous of Sage Creek, Dakota.
PHASGANODUS.

PHASGANODUS DIRUS.
_ Leidy: Pr. Ac. Nat. Se. 1857, 167.
Described page 289, and represented by Figs. 23, 24, Plate XVII. From

the Cretaceous of Cannon Ball River, Dakota.

CLADOCYCLUS. ?
Ciabocycius ? occIDENTALIS. |
Leidy: Pr. Ac. Nat. Se. 1856, 256.
_ Noticed page 288, and represented by Figs. 21, 22, Plate XVII, and Fig.
5, Plate XXX. From the Cretaceous of Sage Creek, Dakota.
CLUPEID2.
CLUPEA.
CLUPEA HUMILIS.
Leidy: Pr. Ac. Nat. Se. 1856, 256.
Page 195, and represented by Fig. 1, Plate XVII. From the Eocene
shales of Green River, Wyoming. °
CLUPEA ALTA.
Described page 196, and represented by Fig. 2, Plate XVII. From the
Kocene shales of Green River, Wyoming.

348 i

CYPpRINID&.

MYLOCYPRIN US.
MyLocyPRINUS ROBUSTUS.
Leidy: Pr. Ac. Nat. Se. 1870, 70.
Described page 262, and represented by Figs. 11 to 17, Plate XVIL
From the Phocene of Idaho.

SILURID&.

PIMELODUS.
PIMELODUS ANTIQUUS.
Leidy: Pr. Ac. Nat. Se. 1873, 99.
Page 193, and represented by Figs. 44 to 46, Plate XXXII. From the
Tertiary of Big Sandy and Green Rivers, Wyoming.

FAMILY UNDETERMINED.

XIPHACTINUS.
XIPHACTINUS AUDAX.

Leidy: Pr. Ac. Nat. Se. 1870, 12.

Described page 290, and represented by Figs. 9,10, Plate XVII. From
the Cretaceous of Smoky Hill River, Kansas, and L’eau qui Court
County, Nebraska.

GANOIDEI.
Cycloganoidet.
AMIA.
AMIA UINTAENSIS.
Amia (Protamia) uintaensis. Leidy: Pr. Ac. Nat. Se. 1873, 98. :
Page 185, and represented by Figs. 1 to 6, Plate XXXII. From the
Bridger Eocene of Wyoming.
AMIA MEDIA.
Amia (Protamia) media. Leidy: Pr. Ac. Nat. Se. 1873, 98.
Page 188, and represented by Figs. 7 to 11, Plate XXXII. From the
Bridger Eocene of Wyoming.
AMIA GRACILIS. ;
Amia (Protamia) g gracilis. Leidy: Pr. Ac. Nat. Se. 1873, 98.

Page 188, and represented hy Figs. 23, 24, Plate oo From the
Bridger Eocene of Wyoming.

J49

HYPAMIA.

HYPAMIA ELEGANS.
Leidy: Pr. Ac. Nat. Se. 1873, 98.
Page 189, and represented by Figs. 19 to 22, Plate XXXII. From the

Bridger Eocene of Wyoming.
FAMILY UNDETERMINED.

PHAREODUS.
PHAREODUS ACUTUS.
Leidy: Pr. Ac. Nat. Se. 1873, 99.
Page 193, and represented by Figs. 47 to 51, Plate 193. From the

Bridger Eocene of Wyoming.

Rhomboganoidei.

LEPIDOSTEUS.
LEPIDOSTEUS ATROX.
Leidy: Pr. Ac. Nat. Se. 1873, 97.
Page 189, and represented by Figs. 14, 15, Plate XXXII. From the

Bridger Eocene of Wyoming.
LerpPiIpostrus q
Leidy: Pr. Ac. Nat. Se. 1873, 98.
Page 190, and represented by Figs. 16, 17, 25, 27 to 30, Plate XXXII.
From.the Bridger Eocene of Wyoming.

-LEprpostEvs SIMPLEX.
Leidy: Pr. Ac. Nat. Se. 1873, 98.
Page 191, and represented by Figs. 18, 26, 31 to 43, Plate XXXII.
From the Bridger Eocene of Wyoming.
LEPIDOSTEUS NOTABILIS.
Leidy: Pr. Ac. Nat. Se. 1873, 98.
Page 192, and represented by Figs. 12,13, Plate XXXII. From the
Bridger Eocene of Wyoming.

2a PYCNODUS.
Pycnopus FABA.
Leidy: Pr. Ac. Nat. Se. 1872, 163.
Described page 292, and represented by Figs. 15, 16 Plate XIX. From
the Cretaceous of Mississippi and New Jersey.

3590

PyCNODUS ROBUSTUS.
Leidy: Pr. Ac. Nat. Se. 1857, 168.

Noticed page 293, and represented by Figs. 18, 19, Plate XX XVII. From
the. Cretaceous of New Jersey.

PycNODUS CAROLINENSIS. .
Emmons: North Carolina Geol. Sur. 1858, 244, Fig. 96.
Noticed page 294. From the Miocene of North Carolina.

HADRODUS.
HaDRODUS PRISCUS.
Leidy: Pr. Ac. Nat. Se. 1857, 167.

Described page 294, and represented by Figs. 17 to 20, Plate XIX. From
the Cretaceous of Mississippi. Specimen discovered by Dr. William
Spillman.

Since the determination of the reptilian character of the genus Placodus,
I have suspected that this one may also belong to the same order.

Placoganoider.

ACIPENSER.
ACIPENSER ORNATUS.
Leidy: Pr. Ac. Nat. Sc. 1873, 15; Am. Jour. Sc. 1873, 312.

Among the fossils in Mr. C. M. Smith’s collection from the Miocene forma-
tion of Virginia, previously mentioned, there is a dermal plate of a stur-
geon, especially interesting on account of the rarity of the remains of
fishes of the same family.

The specimen is represented of the natural size in Fig. 58, Plate XXXII,

and is nearly entire. It appears to have been one of the lateral plates, and
indicates a species about the size of our common sturgeon of the Delaware
River. Though exhibiting no positive distinctive character, it most probably

pertained to a species now extinct.
ELASMOBRANCHI.
FHolocephah. :

E:DAPHODONTIDZ.

EDAPHODON.
EXDAPHODON MIRIFICUS.
Leidy: Pr. Ac. Nat. Se. 1856, 221. . :
Described page 306, and represented by Figs. 6 to 12, Plate XXXVIL.

From the Cretaceous of New Jersey.

Jol

HUMYLODUS.
EUMYLODUS LAQUEATUS.
Described page 309, and represented by Figs. 21, 22, Plate XIX, and Figs.
13, 14, Plate XXXVII. From the Cretaceous of Mississippi.

Plagiostom.

SQuUALIDZ.

LAMNA.
LaMna - ’ .
Described page 304, and represented by Figs. 44, 45, Plate XVIII. From

. the Cretaceous of Kansas and the Chalk of England.

a ————— 7
Described page 304, and represented by Figs. 46 to 50, Plate XVIII.
From the Cretaceous of New Jersey, Mississippi, and Kansas.

OTODUS.
OvToDUS DIVARICATUS.
Leidy: Pr. Ac. Nat. Sc. 1872, 162. ;
Described page 305, and represented by Figs. 26 to 28, Plate XVIII.
From the. Cretaceous of Mississippi.

OXYRHINA.
OXYRHINA EXTENTA.
Leidy: Pr. Ac. Nat. Se. 1872, 162.
Described page 302, and represented by Figs. 21 to 25, Plate XVIII.

From the Cretaceous of Kansas and Mississippi.

GALEOCERDO.
GALEOCERDO FALCATUS.
Described page 301, and represented by Figs. 29 to 43, Plate XVIII,

From the Cretaceous of Kansas, Mississippi, Texas, and England.

HyYBpopontTip&.

CLADODUS.
CLADODUS OCCIDENTALIS.
Leidy: Pr. Ac. Nat. Se. 1859, 3.
Cladodus mortifer. Newberry and Worthen: Geol. Sur. Hlinois, vol. ii, Pale-
ontology 22, Plate J, Fig. 5. St. John: Hayden’s Rep. Geol. Sur, Nebraska,
1872, 239, Plate III, Fig. 6; Plate VI, Vig. 13.

Described page 311, and represented by Figs. 4 to 6, Plate XVIL. From
the Carboniferous formation of Kansas, Nebraska, and Illinois.

CESTRACIONTIDZ.

ACRODUS.

AcRoDUS HUMILIS.
Leidy: Pr. Ac. Nat. Se. 1872, 163.
Described page 300, and represented by Fig. 5, Plate XXX VII. From

the Cretaceous limestone of New Jersey.

Acropus EiMMonsI.

Leidy: Pr. Ac. Nat. Se. 1872, 163.
Acrodus. Emmons: North Carolina Geol. Sur. 1858, 244, Fig. 97.

Attributed by Professor Emmons to the Miocene of North Carolina.

PTYCHODUS.

Prycnopus Morton.
Agassiz: Poissons Fossiles III, 183343, 158, Tab. 25, Figs. 1 to 3; copied in
Figs. 773, 773a, of Dana’s Manual of Geology. Leidy: Pr. Ac. Nat. Se. 1868,

205.
Palate-bone of a fish? Morton: Syn. Org. Rem. Cret. Group, 1834, Plate XVIII,

Figs. 1, 2.
Described page~295, and represented by Figs. 1 to 14, Plate XVIII

From the Cretaceous of Kansas, Mississippi, and Alabama.

PryCHODUS. OCCIDENTALIS.
Leidy: Pr. Ac. Nat. Se. 1868, 207.
Described page 298, and represented by Figs. 7, 8, Plate XVII, and Figs.

15 to 18, Plate XVIII. From the Cretaceous of Kansas.

Prycuopus WHIPPLEYI. .
Marcou: Geology North America, 1858, 33, Plate I, Fig. 4.
Described page 300, and represented by Figs. 19, 20, Plate XVIII

From the Cretaceous of Texas.

PrycHODUS POLYGYRUS.
Agassiz: Poissons Fossiles III, 183343, 156. Dixor: Geol. Sussex, 1850, 363.
Gibbes: Jour. Ac. Nat. Sc. 1849, 299, Plate XLII,Figs. 5,6. Leidy: Pr. Ac.

Nat. Se. 1868, 208.

From the Cretaceous of Alabama.

PETALODUS.

PETALODUS ALLEGHANIENSIS.

Leidy: Jour. Ac. Nat. Sc. 1856, 161, Plate XVI, Figs. 4 to 6; Pr. Ac. Nat. Se.
1859, 3.

Sicarius extinctus. Leidy: Pr. Ac. Nat. Se. 1855, 414.
Petalodus destructor. Newberry and Worthen: Geol. Sur. Illinois, vol. ii, Pal

ontology 35, Plate II, Figs. 1 to 3. St. John: Hayden’s Rep. Geol. Sur.
Nebraska, 1872, 241, Plate ILI, Fig. 5

Described page 312, and represented by Fig. 3, Plate, XVII. From the
Carboniferous formation of Kansas, Nebraska, Iowa, Illinois, and In-
diana.

Ichthyodorulites.

XYSTRACANTHUS.
* XYSTRACANHUS ARCUATUS.
Leidy: Pr. Ac. Nat. Se. 1859, 3.

Page 312, and represented by Fig. 25, Plate XVII. From the Carboni.
erous formation of Kansas.

ASTERACANTHUS.

ASTERACANTHUS SIDERIUS.
Leidy : Pr. Ac. Nat. Se. 1870, 13.

Described page 313, and represented by Fig. 59, Plate XXXII. From
the sub-Carboniferous formation of Tennessee.

Ral.

ONCOBATIS.
ONCOBATIS PENTAGONUS.
Leidy: Pr. Ac. Nat. Se. 1870, 70.
Page 264, and represented by Figs. 18, 19, Plate XVII. From the Plio-
cene of Sinker Creek, Idaho.

TRYGON.
TRYGON
Indicated by the basal portion of a caudal spine, represented in Figs. 54,
55, Plate XXXII. It resembles the corresponding portion of the caudal
spines of our common whip-sting ray, Pastinaca hastata, and would appear

to have pertained to a species of about the same size. The anterior, shining
45 G

enameloid surface is strongly wrinkled longitudinally, and the lateral denticles
are directed downward.

From the Miocene formation of Virginia. Specimen discovered by Mr. C.
M. Smith in the blue clay beneath the city of Richmond.

MYLIOBATES.
MYLIOBATES
Indicated by the basal portion of a caudal spine, represented in Figs. 52,

53, Plate XXXII. In its relation of breadth to length, in comparison with |
the spines of ordinary rays, it would appear in the complete condition to

have been upward of 8 inches in length. The specimen, however, becomes
rather more abruptly narrowed at its upper broken extremity than appears in
ordinary spines, so that it may have been proportionately shorter than usual.

The transverse section has almost the Greek ¢ form. In front the spine *
is concave along the middle and convex at the sides; behind it has the
reverse arrangement. The lateral denticles are directed downward and
backward. The anterior enameloid surface is strongly wrinkled along the
middle groove, but not so much at the sides, except at the base of the spine.
The posterior surface is moderately ridged. __

Specimen found with the preceding in the blue clay of the Miocene forma-
tion of Virginia. From Mr. C. M. Smith.

INDEX.

[Synonyms ate in italic. ]

A,
; . Page.

ANGHM DO DDORIS soe nese eben sera renee O sees se 288

AGH ICING? OATHS boches cosene casece eeneee 350

ANGHOITES oeeodaeeee Gb ereseb Haccidesoon cere 300, 352

IB UAIMON Slee hemi ey sete inwe i 301, 352

Inu cat Ree ee ee eee ener 300, 352

PAD OCUS DYONVNGENSIS =. == mm nine anim == 2 22 = 341
Wenioghcerus antiquus)-2--2------se-4.-e-- 216, 319
Vatiironsis ssc ccces,2 ste cet 216, 319

PANT Uae rset crscinicpeitecis/nicuei2 ciceis x ulnn a enacmais 185, 348
POMACH Ss erystetaiastonsin15 5.52 sia\s,2i2,4 n= 2.5518 188, 348
TECHIE) ¢ ee ci See Ol Ae aed Sen es 188, 348
WHT CTEIS SE Se See ee ere eee 185, 348

PAUIC HT OUUS) Sr miataleiaieimin,winicseiein|-=eiiee == <= 328

iM een eee esos senoas eee 72, 328

: VOUS oo eieicin.n join asia mee aisiets - 329

AND@OnINSUGED Pisce sasece ogee ed seen -eeae 322

PAMCHMMGMERUUNN : 2226) cam onic 2 e~ === 218, 250, 322, 323

HUIS cosscerssonsccn 16 tedc 251, 323
AUIStUAle NS, «dra /a suysiasciste one 250, 323
IBBINGT, bas eisis\anrco sls) eae 218, 252, 322
Condont seismic ijt ee eie! steele 218

PAMOSHOIA OLNATA -.-2.--50seccre eeemenne 174, 341

PiphMACOUMeRd ee) < «to -- cnea cane scene neee 320

PAU ROM CNB ies alata lain /aimey a niaiaiey wis tm Sei Saat 338

PAP ALORS Me aiefete eins 3)a/siate, alojeiniieiaieimiminiay~.e's eer 266

PARE OULERUUME) =\ajsiaim: tuts 2 cis ici. 5 icha\e) a nies! = sia’ 320

JNRICURICIME) 6 Ooo5e NESE Rea eee Se oreemeEee 216, 317

Asineops squamifrons .....-.. .----..----. 195

PMMMCMSI Sica. <ecccemesannna nue 195
ASHerACAMtAUS SIMeTIUS.--. 0 .-cce0 enon a-<- 313, 353
Atlantochelys Mortoni .........-.......... 269, 342

UDOLOSUSE --eeeeciqeeee.co-s 342

PACH EM ages ieismia acca seeaensewscine s 255, 317

MUON ALC) eee mmte, =i events ease 255

MES LORNA emer eee ceca eee sce 255, 317

B.

BRED. coca canons | aéobeo GOSO OOOO ESO BeeoRE 160, 341
PWS: ssn 0 cdc Gabo ba00 pene nSecto rene 163, 341
ARON OS REE e tae emi ei ania’ scetcemances LOL sal:
UCENG) 3 552 BCG ORE ER CCE OC eIee 169, 341

ISHIDIGUIS = chas dos a5r SPC ee POOeeEs Ee eeecoeee oY Aer Ul

WYOMING ON SIS cee eels s a <= <= 157, 341
iSOmelaGiEONS =< -.8e emesis, oeecmserse 253, 318
IBOWIGES 6a 5 Sco GOS aGICEe aeO se Se ee ene 318

C.
Camitdie! js. ene SOSO EE ECOe nae aco er eee 315
Canis indianensis..........-. ..- er eae 230, 315

Page.
Camisinnimn @uuste satay oes heen cece ce oe 315
VOU, Gae0aG CosSen SHES PRO SORE Eee 315
Wameli Gaeta ns teeter seas ecie erica. ss ma 317
(CEiB mi Oaa Ws SALE Be ate ee ee 114, 227, 315
WOLD te sees ani ace wes esislsjecls nein ssi cmwa 317
CeSiTACIONAG cecsse execs Saceee ane assis 352
@etaCeaets sees sissies see oy lcce Sinha wsice 337
Chameleoipristinus =. .22- :2-5-. +.2--2--- 184, 345
WHELOUT Ate oe mie opeoero a co ase ees 132, 223, 260, 269, 339
Chisternonmnndatum.c--+ 2 2ss-4 2.2655 cece 169, 341
(GHUSLORTAU arn erence. Wee see eens a= <a 341
Cladocyclus occidentalis ...-.....-....---- 288, 347
@ladodus occidentalis. - 2-2-2 .22 se... se cee 311, 351
MOTE E)? Sasicina siosisin so aclne meee 312, 351
CNM ASTGS ees oe etoreeretetaiae eisaceeies oe ieniecwpinns 281, 344
aH MIS eee ab Sy eins speak ieee ig ces 283, 344
THCOLINECGIUS! Ws 32cm. soc afs nos a arere 281, 344
(CUM. spear a sabe seeecSse Sees Ss sass Set oSe 195, 347
fs Vict C0 al i taal tls ete aie eae i 196, 347
TIS heres see sale = omens ose mate 195, 347
jPEIO, | Sao See eo betes eenesete 195
(Ci OES) S35 Se ee eeeee Boge nue ce meee ree re 347
CORA CLOROOOI nein aaa ie ected) cienie 301
WNOCOUIA = ssa are hel oon cm emocaaee eee 125
WELOCOOUINS cere coe cee cesar 125
Opi essteosececosres ase ce Jee 126
WBE eaters sera oe caret ten yeas 123
WV ClOPANOIEl! <2 — ae came en inn en 348
(CHANG EOIE) sponse soe ce8 one Soo ss Sec see Ree 343
ANCISUS | =o = mi= sieseisisias seicia wiersisioe 269, 343
Cyprinide -..-........----- Se Seeess peecae 262, 348

D.

Delphinidg ..-....----.--------+--------- 337
IDICORVIOS see Sel cee a lem Were reine faim eintnloniale 216, 319
ES POMS ieee ten = i ioe 217
DS Mane sda actions Pe eR HoeRee 216, 319
DETOURS Gaies ah tes eoeeimns COG seem or aeno 232
MAGUSUDISI Nes meee ace oie eieretciol= te 95
II CARIS tee oe cata sl asrelcy aici 334
HC eecepoos, Sosoos face 95, 108, 332, 333

Dmosaunia--s-. <1 -----~ Soce, Aivic8is

E.
idaphodon mirificus.----.---.---.-...-... 306, 350
idapphod ont decease eee nase = ae ea 350
PASM ODLANGMIN see teens a's ig a eos aO
IDI WANS sas eee Goneasclase5 Hoe epee eeeeee 238, 329
DMEKICAMUSHe eae steele eiaintaaitn ee O nooo
GUNN ostcacrosy sesso gasseogooe 238, 329

356

Page.

Dlephas imporator. ...--. .----+ --00 ---- += 329
ST GOCCUTIULA acti eisctalaslgr tata oleate ap ete fete ete 329

loth erin = aes sees es ale eae ae 124, 217, 320
MeO mg come Gogsancesd 2c 217, 320

Wa mo canperopoAer Jace ec 320
leNtIBic-ccccas «occ s see 124
Moxtontiaa-.ne:c-s6 cet crepes leonecU

SUPOLOEM oe. eekae nS 218

BMYS-= eee nee ee seis oecineais-iae eae ao cOU.
CURR Oe. che eeciset nace neeee ole eee LOIRE
THONGGNG. <0 22 S26 theme nica AU doo a0)

.140, 143, 340
.... 260, 340
140, 141, 340
140, 141, 340

WCANST I= claycie ate came ecient ers min cess
DOO So kaa AS Rees soso scseSe
SLEVENSONUAINIES Ha) sie-oya fe ciee ine een
WVOUMMOCNSIS) sees sales = ele lt

HMChOdus SHUMALG sess eeeeee ere eee eee enc Oo Onn
LENIGLIOMON) morse eive cree aeetee 32 )ne ee ieeron ete 320
SHOUASILENSY aise aie eaacintee web Oe eae De NOO
IQ UMUEB cess eleean.siscieeai se ator ace ere 321
ID POC aoa soa us Scomeseanas choSeasbn0-0c0e5e 242, 321
CONUPULCOMUS =e eam ee wecsn ese ones 244, 321
CUCOLSUS esos Sue een Ea eee 243, 322
WIRE oa Soo dor Con Op Onea S056 aawaee 244, 321
occidentbaliseceene sek see Cease 242, 322
JOU 2 >= o555035 Gene csosepoassse 322
PALVWUS Hse eee eee Seer ecOe ore
Erismatopterus levatus -..---.-------.---- 195
ISMORSEGEG so s500 5550 c0oC 195
TORGRNT/ DMM mae saseaenes so6es0 S5oshS 5S55e5 212
Huelephas Columbi .----- -- SosgEcotsy pauane 330
HCURODD Senses sascubesoosses sa5s 330
Kumylodus laqueatus..-.---..---.-------- 309, 351
135
IBGE aS cad csques Soadeadace Read anes Glos 315
EUG AUGURUUS..coscod teen ookcss Seon sosSee 227, 315
TM POLiahiswatesssisece See eeetes 228, 315
IMG socaeuadsas Sieh Set gelnctivces 184, 261, 288, 346
G
Galeocerdofaleatus=eceese eee eee ees 301, 351
Ganord6iwsaswncae Seas Soph ne aeUeee ene 292, 348
Gilly ptosaubuss cc so sede oe oc siecis eee eee 182, 345
@eclenniS —c46 655500 neoosnsas5 183
Graphiodonivineariiss-ea-seecseecee eee 337
Hi.
Hadrodus priscus- .-----.-.---.--.---.---- 294, 350
drobiyusismpLemMws =e see cesses ae ee 222, 321
Ehippanioniispeciosumis ses-eeeee aesee ee 247, 322
TEM OSH UE) IOPMOSIS oac5 osonos aes cero Saec 91, 321
d TODUSHLOR-- See saess ease eres 93, 321
LEMONS GOMOUAG osa5 sobs. cena azocas soa005 342
COPMPRBUS Has 5c Ho dae eo eae Osos
Holocephalits< 2a22.5 sac, aseesssceneee use 306, 350
Ey bemiysiarenarius| sss s2]-s4) eas eee 174, 340
Jshy vous) Boog coosemooaEankeasae 255552 351
IED OSU S eGoccosasaad nsosen sabes mana cece 75, 320
TMPNOOWNS) sa 5ec0 sas5as oses ose 81, 320

Page

Ely pamia elopansecr 2 ercue ss. et le 189, 349
Ely tachivn ater cn oo) sora ele satnw cmos enh. 59, 327
BUURNIVG seer ie he eee nas a oe 60, 327
CQNOSIBNER seam ameete ote oan ane 60, 327
OXIMUNG) con pie eee hee sane . 66, 327
« MOdCStOB’= 5-2 sseewes socoseee as 67, 327
NED pe Omeraeal Shaman oo Se 67, 327

if
Tchthyodorglites voc. ..ees. soo ee 353
etithyOrnis) jlo nse see nee 266
Ineectivoral::<-.2-5:s2.cs-2 es ess. eee 120, 336

L.
Labride -....-- [ie seh piven ein 346
Pa Cera vscnesae-50) emcee eee 180, 285, 344
MaMa) = soe ase eats eee 303, 351
cuspidata <5. <<. «cine 3.6 pee eee 305
eleganse-cq-c sees s= te te dee eee 305
PexaNa, 5 e-kwi5.54 ske<c ake Cee 305
LEAR MOU Di aosee 33537 2554 6528 Sess 2555-2 -- 332
Ihepid@steus\-- 2261-2 5- eae ee eee 189, 190, 349
ALTON see cee ccele eee eee 189, 349
notabilis: .\..---dsceccn ee eee 192, 349
simplex... 5224 :2c seuss eee 191, 349
iseptomerysx< Hvansl o--en eee ee eee 216, 317
Lestosuurus corypheeus -.-..----2 -.-.---- 76, 344
TPIMRONYUS' wee 2 = ae ee eee a Ree 57, 323
WBVIAENS 2,253.5. Seepee OEE eee 323, 325
laticeps <..<-. .cets sae 326
TODUSTUS «:a\= v0.22 Sac e See Eee 326
Evmnothertum elegans .----- 22222 eee e en eons 84, 320
Limnotherium tyrannus ...-.. ...-....---. 83, 89
TRODON Oj Spelt: ei === ee 271, 343
[DN OTAG Ol mre om (eel loete te ee 344
hophiodon><2f2. seca. eee ee eee 219, 327
BOM QOANUS Sts = ota eee 60, 327
MODES UUS oe me wee eee eae secu eeeee 67, 327
NONUS aero =) <a ram slaila eae ee es
occidentalis:;-.ny+. <2 See 220, 327
parisiense = 7s<:=. 22545) eee 98
ophiotheriumy (3455-4554 see eee 69, 327
; Ballardi -. 224052223555 71
Sy lvatiCOMm cock Sees eee eee 69, 327
TOnOlOPROdON = .ataroree Taree tere ee ee ee 332, 333
Wouras 2s entece ct sce tones Oe eee 230, 316
Piseinarial 3555 > a= poe 4 eee 316

M.
WAGOECOD ORY DKOTIGR sa sas8 Keoced salccs oc2 340
Malacopteric: Jos o225 322) <2 eee 294
Mammalia = .eecsassseeeoe eee 27, 199, 211, 227, 315
Manatusmmormatuss.--2) 6222) 7 eee eee 336
Mastodon)..25- 32.2220: Sss2se> case eee 231, 330
AMELICANUS' = sas. 's =e eee 237, 330
anceps <2 .22 as 42 eee 94, 334
TOITACUS 6s ce cet es ee 237, 330
ODSGUTUS cance se 5 aoe pee 231, 330
Shepard. ..3.35.55452 so see 235, 330

357

Page
Megacerops .----..------ guctecesosp assess 239, 335
coloradensis= <--- --- 2.2 2.-.---- 239, 335
Megaceratops coloradoensis .,--.---.-------- 335
Megalomenyx -..--------------. -----.---- 260
TOURONENS1S eee eee 260, 317
Merychippus - ..--------------.-----+----- 248, 322
Tope C58 Sooo cosbeepeeend 250, 322
Wet V@nyUS ss.s26 neces assessseeses Goes 202
TS ee 201
MAIO cov szen osoc dod asec 0Re5 201
WAGONS --scssqusssaebas wooo dees 201
Merycodus necatus .--.-. .---.. ----.----. 318
IMerycochorus ---- --e--.---- -----= 199, 202, 208, 319
JUMODIS scenes om 2 sa5555 oe
PUSHCUSlas-crsceasecineeoaleeae 199, 319
INN AGIS o.cceeempees See Ee eee pen BemEeeoge oser 316
Microsus cuspidatus .-...:---.----.---.---- 81, 322
WNGICS@USlacke Sheb cescco pees cebers soe 82, 320
elegans ..---.----. FOGuA Seen acs 84, 320
i gracilis ...--- pisisixian. acinjaleminareten 83, 320
WIS AIS AULA state sets apa aa aayal =a) is/-nsals wim saci 270, 343
TORE RDITTD ook SS ieeoes cose eo ee ePeeeEree 279, 343
Mii CHEW merce Aeneas sano mise 342
DWI eet aia teininie els cicicie ame ociemiee secsen 336
IWlwehisliGlesy . .oaSee oocoad aBseSRebeneeae aes 316
Si) vig ap baer en ae 353
Mylocyprinusropustus.--.-..----.---5--.- 262, 348
WIV SOD see aa cscs cdccad one clgisnue ven 111, 336
TRAINS atenk HeOae eee ee eee *. 112;336
MANNS Ae ae sete scene sie sie ack 111, 336
N.
PNOUURC UG NODUSTLON sx = a nei wel e es scims ees 93, 321
Notharctus tenebrosus -..-...---. ..-...-- 86, 329
Nothosawrops occidwus..--. .--.------------ 287, 345
Nothosaurus occiduus ...--..----. aoustehee 287, 345
O.
(Qa TO), Ae Seq ease seEe ee eee eee eee 319
Omormiys Carter... 62-2 .<)s<0 seis en Snes omnn 120, 336
Oncobatis pentagonus -.---..----.-.--.-.- 264, 353
Oligosimus grandwvus..-......-..---..--- 286, 345
(OneCall Seen e eee e eee ae ee 318
(OnECHON << Se COs EE Soe Tee eee 201, 211, 318
ARMS 3 iafaia) oe eoae aot ob ancora 212
JOE Se oem Osco se ieret steerer aera 212, 318
@ullbertsomits. cosas .ccace seb cee 211, 318
TACHI Sees ayrolyciaiere aie Giclee Michereea(e vacanee hil
INFDOGITS ood rasedd Sebo SaRron aac 212
TAVOP osenccson Aeseenqesnee Gsoeee 211
GREENS) SeGa6 Socnboceeces He5c 318
BUEN DUS eyeta eveece aes Si ciatsie aicmes 211, 319
Osteoglossum encaustum.....-.-..-.--.---- 195
OPodusidivanicatUsi..coce.saccce sects oo. 305, 351
Oss DM aeaciecsieeccicicie see Seles wok ke 302, 808, 351
ORO MAK ete pete seein: spore sa ercisraremrd 302, 351
1B
alee NCOMOM mses mnen aed ee leis a tciae nies 122, 336

VGUUS tamemersasetecas) Vic neicnmeets 122, 336

Page.
IPHIEVOSM OMS s55555 5450 95565005 35534 osdbos 27, 323
humilis: soca acose seo ee ee 58, 326
UNTUS See wee bees seeelee ee romel= 57, 326
GU Rs «eae Baan EEGcn rep asen 326
Laicen se aemese a cee ee ae 325, 326
MND] Olesen tee ave eries tee eee ene 45, 326
MINOT eras cee etaraneeee Se eae 72, 328
Paludosuspasemes =~ ten =e eee 28, 325
Palauchenia magna .------.-- ---.....---- 255
Panay Swe aee Aaseeta eee emcee LOO ooo
MeEliCAtlOle peer renee ee ecer Gee ee 110, 335
delicabissimUs 2 eee -0=-2--2-5-5-- 111, 335
Gelicabisie seers oeese eee ceases 110, 335
Patriofelistulta; sect semaas aossceeeee- se 114, 316
Rerissodachylareanseses—, <es=s/2so— 22 se 27, 219, 321
Petalodus alleghaniensis--.-.--..----.---- 312, 353
GESURUCLOR Aa ene aia fos oere tea etotet ee 313, 353
iphareodus acntus\..o-).252c0 ccs -2 oa eee ae 193, 349
JEG Rap 06 RGIS io eres poneer ceeeed OSeSee 289, 347
Pimelodus aniquus! ese ses meee ces w= =e 193, 348
aC OP an Ol Clie ieee islet siete sire oie ie 300
PI AOTOSCOMM eae a) sameeren cise ares etel sistas 295, 311, 351
JANEW ES Seco Becenc Booms CaS aCeon oer ece 342, 344
GUD EN OBUS etcetera oe fare oracles Gases e 342, 344
tympaniticus -.-.. -- ood sere sede 342
Platygonus'Condonic. 222 .)-.-..- --2. 2. 217
Poicilopleuron Bucklandi ...--. ---...---. 268
MELONS wutpiebes Pactcs sceod 267, 338

Polycotylus latipinnis’ ---..--.\--------.---- 279
Pontobasileus tuberculatus........--.----- 337
PTO DOSCIO Ca sania etoaats a anise ersicac celeene 93, 231, 329
Procamelus occidentalis ........ ..-.-.---- 258,317
EO DUAUGHSIG =e etcetera 317

TODUSUOM sina csicleseis semecn, coms, SOO ane
VIEPINIONSIS 2-55. s-2-----cea5 200, aL!

RD HUN aT Ae. ooledetera ce eiaeieians brew ommaroam'e 185, 348
Protautoga conidens......-..--.---.------ 346
PEPOLOCIUINELUS ois acintns ese Sercer ase Bce ae aele 317
IEE OUGHID DUS memos ee Sista a mianeaace stoma 248, 322
perditus:....-..-.-...---...249, 250, 322
WAGs fase sece elt mio) aCe

BROLOShOP MIPIM AG. cece sonelq sim =< aia 269
MEV GUNN ain etalon apes Sear ieigaars see 342

WER OSG Det oe, a as Se olan ees 269, 342
PtychodusMontoni) nce =)- eee cane wee ous 295, 352
OCCIGORTAIN osc Sonn ca cete nem cine CUS ODS

(OWENS! oansoce omen Soodsogsa5 352

Wiltinppleyics S22 cect ee see eee 300, 352

IPYCNOGUS! ssssensescics ssccmeses wees se Sleae 292, 349
CAROMMONSIS) oj ejascesisnceee seco 294, 35(
faassen stan a Sucta cane seers Same 292, 349
FODUSUUS%S on 2 Sucsce sees ceteece 293, 350

R.

Lata See Ss ha Se cae aa ee 264, 353
Reptilia eee twas et eceee Sei sssee sce elacice 125, 338
Rep tilegeycast= ate cee mesa cenis Hosa ces seer 267
Rhampnosaunus. ane seas RET eens 271, 343, 344
FUN O CONOSSese renee teers clear oo Se ee ae 220, 328
BOMOCtANS i asst er te Sele eres ae “ 328

Page. Page.
Rhinoceros hesperius..---...--...--...--- 220, 328| Testudo Culbertsoni ....2... .-.--0------0- 339
OCCIRENTATIGE ninyota a'ala finer tettete = 328 TEMAS INEN CA <n n'can heme se Nee oon 339
OYESONENEIS </-\-ce5 erecta ceemen 328) . TL ROCCE BOONE oe eee Are 339
MAGIACUS ak \cicin nin cine See a 221, 328 NCDIASCENBIN = eaten 339
RRAMOBMUINUSS eae Gace enaieee eee 271 MIODYATeNsIG <= .2 2S ee eee ae 340
OETA P55 a Ace O86 eoccis os 5587 343 ‘ OlCZONCUAISE eee =.= eee a ee eee 340
DNONIG Ol im < nro msinde nee aon eee 344 | Tetralophodon mirificus .........--..--.---- 330
Rhombocano dele) eee ee see 349 | Tylosaurus dyspelor ....-.....-.-....--.-. 271,348
itvnchotherra my sven see see ase eee 237, 330 PLOTIGEY (aos i ss. 2 ee ee em
Rodentia ssi cloweisemtemheniateaicenevaaee 109, 335 | Tylosteus ornatus -...-..-....-...-...-... 285, 345
IM parhonels Aqsa aaaeosooes Saisie Se LOO N21 253; OL7) |) inocenasucs «neocon. 2 eee 331
S. ADCEDS a (= 9 an a )s onic ee eee
TANCIG - 22.050 /-c pce on ee Se
Saniva - -- pemsGie ssc ia eI Oo 181, 344 un QNCEDB a < ian 22 Se 94, 334
Saniwa ensidens -.....----..--. -....----- 181344 iacodon fallax: 14.0.0 eel : 123
PAAR DOS shar eas OO OC ORC OG OCOn 181, 345 (Trionty Chids6 x=. 5cc.2 jas eco ee 341
SauropteryBia--------. + --- 222-4 oocoo 286, he (rionyx...:-:--.2..c2-. 2.0.80 eee
Sciuravus .---2-22--0s222 veces eee sere ee 113, ee guttatus 2. 222.22. ep
ES a ne uintaensis..{............- 22 Sueee Segoe
my UNdANS -.----- 2 oe nme en enn ae thy Trogosus castoridens ...........-....------- 71,328
Sciuride Fe ce ea poe BOUUUG «oi 5.2 5 5, onto ee
SOGURING CHING .c50 56060 cha5c0 coaese cose 353 Gregor osc dees sn ‘ 953
Silwrids seis aixtec-eesemsce toaemee eee ese li! i nT
SIMOPai ss cgsscise tae eisieiele sel eee eee see 116, 316 U.
Sina ae one eee ee ee 118, 316 | Uintacyon edax ......'..-.---. ----2. 72s seeilenetis
WAP AR = cS a-s:s seaya/s mesinias So slaps repeat 116, 316 VOLPAR 202 c0n ato. see eee 120, 316
Sinema oese see mmas on sae eae ee eee Ree 350) MUUntamastiti anes eee eee ene eee eee 331
Solidungula .......--- Paley seve eepeeere 208, 218, 242, 321 QUWN00 os ie.2 cad hace ee 94, 107, 333
SyaMeNAEIGNGED < oo5056 sbb60ssosonHouteds ose 342) i Uantat hermes ee ee see 93, 331
Spby rend eractis fea enh cmescecciserie cece 288, 347 ANCePS\.s-nissocas se eee 334
Squall Sree soe. sc cms cece fore asian eee 351 Miravile s coisc. cee ee 333
SiyleMYySio- Seas bees ae> soe ceca aes ae 223 TODUStUINE =] ==. === eee 93, 96, 333
Gulbentsontiasae) seceeeaeeee eee aoe 339
ORGVCUGINS Ganad Bscqsens saab cconan 226, 340 ; Ve
NCDVASCENSIS < Beis on eS EE ere 224, 339 Vulpavus palustris -.----..----....------- 1f8
MCDURUREDEIS 6 oe85565 Sano secese seoden 225, 340 Ww.
Suid@ .-..----------- ------ 22-2 eee eee 319 Wiashalkiusiusionisesseeeee == sees ee 123, 336
& x.
Tautoga Soiree MISES Sia a cas ee Sai ore , 346 X<ophactinus audaxeee esse 290, 348
Teleostel .----.-----. --++ +--+ +2-22+ 022 --- 288, 346 Xystracanthus arcuatus-..---..----..----- 312, 353
Tih ad Kan epee cae dar daaoee baba does case 323 ‘ :
Mestudinides: s2eec2. «ac ce ect Dine ecseyess y 009 Z.
_ Testudo Corsoni.-...--- Be essere ame sets 183%) G8) VATHEAMGC OMT 5 coca cacs 222200550522 2-222: 337

je)

me

EXPLANATION OF PLATE I.

Fig. 1. OREODON SUPERBUS:

A side view of a skull, with the base of the cranium invested in the matrix. Specimen ob-
tained by Rey. Thomas Condon on John Day’s River, Oregon. One-half the natural size.

Figs. 2,3. MEGACEROPS COLORADENSIS:
Fig. 2. Upper view of the nasal extremity of the face with a pair of horn-cores. One-half
the natural size.
Fig. 3. Front view of the same specimen

U.S. Geological Survey of the Territories. Plate I

y. SINCLAIA & SON, PHILAD™NPHIA,

HGACKROPS COLORADENSIS ¥

| OREODON SUPERBUS , % Oe}

tere
My
*
fl ‘
“
$s *
s
-
*
mr,
,
ue
ap
‘
F .
-
.
.

Fig.

Fig.

Figs.

Fig.

Figs.

Fig.

~ .
EXPLANATION OF PLATE II.

1, LOPHIODON OREGONENSIS :
Two upper molar teeth, much worn and seen on their triturating surfaces. Specimen from
Bridge Creek, Oregon. Natural size.
2. MEGACEROPS COLORADENSIS :
Side view of the same specimen as that of figures 2, 3, of PlateI. One-half the natural size.

3, 4. ELOTHERIUM SUPERBUM :

Fig. 3. Portion of a lower canine tooth, natural size. From Bridge Creek, Oregon.
Fig, 4. Crown of an anterior premolar, natural size. From John Day’s River, Oregon.

5. ANCHITHERIUM CONDONI:
A mutilated upper molar tooth, natural size. From Oregon.

. 6, 7. RHINOCEROS PACIFICUS:

Fig. 6. An upper molar seen on the triturating surface, natural size. From Alkali Flats,
Oregon.

Fig. 7. An upper last premolar, seen on the triturating surface, natural size. From Alkali
Flats, Oregon.

8, 9. RHINOCEROS HESPERIUS (7?) :

Fig. 8. An upper last molar, seen on the triturating surface, natural size. From the Condon
collection of Oregon.
Fig. 9, An inferior molar, seen on the triturating surface.

10. PATRIOFELIS ULTA:

Portion of the right ramus of the lower jaw, half the natural size. It contains the remains
of five teeth behind the position of the canine. From near Fort Bridger, Wyoming. See
page 114.

. 11,12. HyracHYUS AGRARIUS:

Fig. 11. Left ramus of the lower jaw, one-half the natural size. Specimen obtained by
Professor Hayden on Smith’s Fork of Green River, Wyoming.

Fig. 12. Portion of the left ramus of the lower jaw of a young animal, natural size. It con-
tains the temporary series of teeth behind which the first of the true molars is inclosed
within the jaw. From Black’s Fork of Green River. Hayden’s collection.

~

13. HyRACHYUS MODESTUS:
A first or second upper molar of the left side, slightly larger than natural. From Smith’s
Fork of Green River. Hayden’s collection.
14. HYRACHYUS NANUS:
Portion of left ramus of the lower jaw, with two premolars and the three molars, natural
size. Obtained by Dr. Joseph K. Corson from Grizzly Buttes.

15. Diseased caleaneum (hyperostosis) of MERYCOCHGRUS RUSTICUS. From Sweetwater River.
Hayden’s collection of 1870.
16. OREODON SUPERBUS:

Portion of right ramus of lower jaw, with the three premolars and first molar; natural size.
Condon collection of Oregon fossils.

T. SINDL- 1R & SON PHILADELPHIA

1. LOPHIODON. 3. 4. ELOTHERIUM. ig. RHINOCEROS, lI-la HYRACHVUS
2 MEGACEROPS. ¥.| 6 ANCHITUURITM| 10. PATRIOFELIS. 1 15. MERYCOCHO

16 OREODON.

EXPLANATION OF PLATE III.

Figs. 1-3. MurycocHarus rusticus. Figures of the naturalsize. Specimens from Sweetwater
; Wyoming. Hayden’s collection of 1870. g As
Fig. 1. Upper jaw, with a nearly complete series of teeth, the last molar introdu iced fro
another specimen.
Fig. 2. Front view of the same specimen, exhibiting the high alveolar Ques and the n
row nasal orifice.
Fig. 3. Lower jaw, with a full series of molar teeth.

Fig. 4-6. Tesrupo or STYLEMYS NIOBRARENSIS. Figures of the natural size, except Figure 6, whichis
one-half the size of nature. From the Niobrara River. Hayden’s collection of 1857. —

Fig. 4. Internal view of the fore-part of the plastron. .

Fig. 5. The last vertebral and the pygal plates.

Fig. 6. Internal view of a posterior portion of the carapace, exhibiting the costal ca i
and the processes for conjunction with the pelvic virdle.

U.S. Geological Survey of the Territories

E
}
f

=

T. SINCLAIR & SON, PHILADELPHIA

i-8 MERYCOCHOERUS RUSTICUS. | 4—6. STYLEMYS NIOBRARENSIS.

EXPLANATION OF PLATE IV.

Figures all of the natural size. Specimens all from the Bridger tertiary formation of
Wyoming.

Figs. 1-8. PALMOSYOPS PALUDOSUS:

Fig. 1. A mutilated upper canine of the supposed female, from the same individual as the
specimens of figures 5-8.

Fig. 2. Mutilated canine of the supposed male, from the specimen of the following.

Fig. 3. A complete series of molar teeth and the mutilated canine of the left side of a fine
specimen discovered at Grizzly Buttes by Dr. J. Van A. Carter. View of the triturating
surfaces, partially worn, of the molar teeth; from a supposed male. }

Fig. 4. Outer view of the crowns of the same molar series.

Fig. 5. A complete series of molar teeth, discovered by Dr. Carter on Henry’s Fork of Green
River. View of the triturating surfaces; more worn than in the preceding specimen.
From a supposed female. Z

Fig. 6. Outer view of the anterior two premolars of the same specimen.

Fig. 7. A third upper premolar, left side. Specimen from Henry’s Fork. Hayden’s collec-
tion of 1870.

Fig. 8. Lateral view of an upper incisor. Specimen probably from the same individual as
that of Fig. 5. , :

Figs. 9-18. HyRACHYUS AGRARIUS:

Fig. 9. Outer view of the crowns of an upper series of molar teeth.

Fig. 10. View of the triturating surfaces of the same teeth. From a specimen discovered by
Dr. Carter near the Lodge-pole trail, eleven miles from Fort Bridger. All the teeth con-.
siderably worn.

Fig. 11. An upper second true molar, left side. Found by Dr. Carter on Henry’s Fork of
Green River.

Fig. 12. An upper last premolar, left side, but little worn. Specimen found by Dr. Joseph
K. Corson at Grizzly Buttes.

Fig. 13. A portion of the lower jaw; from the same individual as Figs. 9,10. It contains
part of the lateral incisor, the canine, and the premolars.

Fig. 14. View of the triturating surfaces of the premolars, from the same specimen.

Fig. 15. Outer view of a second lower molar, from the same individual.

Fig. 16. Triturating surface of the same specimen.

Fig. 17. An upper canine, found at Grizzly Buttes by Dr. Corson.

Fig. 18. A lower incisor, from the same individual as Fig. 13.

Figs. 19, 20. HyRACHYUS EXIMIUS. Specimen found by Dr. Carter on Henry’s Fork of Green River.
Fig. 19. Fragment of the left side of the lower jaw, containing the last premolar and the
greater part of the first molar.
Fig. 20. View of the triturating surfaces, much worn, of the same teeth.

G. S. Geological Survey cf the Territories, Plate IV.

T. SINGLAIA & SON, PHILADELPHIA

i-8 PALAHOSYOPsS PALUDOSUS | 9-18. HYRACHYUS AGRARIUS.
iY 200 HYRACKYUS BALMIUS.

is i
a
.
s *
»
Ser
u
.
\
ee
> «
-
>
.

EXPLANATION OF PLATE V.

All the figures of the natural size except Fig. 11, which is one-half the size.

Figs. 1-3 TROGOSUS CASTORIDENS. A lower jaw, discovered in the vicinity of Fort Bridger by Dr.
Carter.
Fig. 1. View of the left ramus of the jaw.
Fig. 2. Triturating surface.of the second true molar, much worn. The other molars are too
much injured to be characteristic.
Fig. 3. Front view of the jaw, exhibiting the large rodent-like i incisors,

Figs. 4-11. PALHOSYOPS PALUDOSUS:

Fig. 4. An upper last premolar, the triturating surface much worn. From Henry’s Fork.
Hayden’s collection.

Fig. 5. An upper last premolar, nearly unworn. This is one of the original specimens upon
which the genus and species were established. From Church Buttes. Hayden’s collec-
tion of 1870.

Fig. 6. Outer view of a last upper molar, left side. Henry’s Fork. Hayden’s collection
of 1870.

Fig. 7. Triturating surface of the same specimen; the outer fore-part much fissured, with ~

the portions displaced and the single inner lobe partially broken away.
Fig. 8. Outer view of a second upper molar, from the opposite side of the same individual.
Fig. 9. The triturating surface, with the outer lobes much worn. Figs. 6-9 are from
specimens, which were attributed to the same species at the time of the original notice of
it in the Proceedings of the Academy of National Sciences, Philadelphia, 1870, p. 113.
Fig. 10. View of the triturating surfaces of the last two premolars and the molars from the
specimen represented in the next figure.
Fig. 11. Left ramus of a lower jaw, containing the teeth just indicated. This fine specimen
was discovered by Dr. Carter thirteen miles southeast of Fort Bridger.

:

U. S. Geological Survey of the Territories. Plate V.

T. SINCLAIR & SON, PHILADELPHIA

1-8 TROGOSUS CASTORIDENS. | 4-11. PALAHFOSYOPS PALUDOSUS.

“EXPLANATION OF PLATE VI.

-

Figs. 1-9. Hyorsopus PAauLus. All of the natural size except Figs. 2,5, 8,9, which are magnified four

diameters. *

Fig. 1. Right side of lower jaw, with the three molars. From an individual past maturity.
Specimen from which the genus and species were first noticed.

Fig. 2. Triturating surfaces of the molars of the same specimen.

Fig. 3. Left side of lower jaw, with last premolar and the three molars. Specimen obtained
by Dr. Corson at Grizzly Buttes.

Fig. 4. Right side of lower jaw, with last premolar and the molars, but slightly worn.
Specimen obtained by Dr. Carter. .

Fig. 5. Triturating surfaces of the teeth from the same.

Figs. 6,7. Left side of two lower jaws containing the molars. From mature but compara-
tively young individuals. Dr. Carter. ;

Fig. 8. Series of the back two premolars and the molars of the right side. From aspecimen
loaned by Dr. Carter.

Fig. 9. First and second lower molars of the right side. From another specimen loaned by
Dr. Carter. .

Figs. 10, 11. Microsus CUSPIDATUS: :

Fig. 10. Portion of left side of lower jaw, with back two molars, natural size. Specimen ~
from Black’s Fork of Green River.

Fig. 11. Triturating surfaces of the two molars, magnified four diameters.

Fig. 12. Portion of right side of lower jaw, probably pertaining to the last-named animal.
Té contains the roots of the molars and the last premolar, the triturating surface of which
is represented in Fig. 13, magnified four diameters. Specimen obtained by Dr. Carter near
Fort Bridger.

Figs. 14-17. MIcROSYOPS GRACILIS:
Fig. 14. Left, side of lower jaw with the molars, natural size. Fig. 15. Triturating surfaces
of the molars, magnified four diameters. Specimen obtained at Grizzly Buttes by Dr.
Carter. i ;
Fig. 16. Left side of lower jaw, with the second molar and portions of the others, natural
size. Fig. 17. The triturating surface of the second molar magnified four diameters.
Specimen obtained by Dr. Carter at Grizzly Buttes.

Figs. 18-22. HyopsopuUS PAULUS:

Fig. 18. Right upper jaw, with three premolars and the molars, magnified two diameters.

Fig. 19. Tritirating surfaces of the teeth magnified four diameters. Specimen obtained
by Dr. Carter at Grizzly Buttes, and apparently pertaining to the same individual as that
of Fig. 14.

Fig, 20. Triturating surfaces of the right upper molars, magnified four diameters, from a
second specimen. Dr. Carter.

Fig. 21. Triturating surfaces of back two premolars and first molar of the left side, magni-
fied four diameters. Obtained by Dr. Carter at Lodge-pole trail.

Fig. 22. Triturating surfaces of upper second and third premolars of right side, magnified
four diameters. Dr. Carter.

Tigs. 23-25. PARAMYS DELICATUS:

Fig. 23. Right side of lower jaw, with all tho molars, natural size. Fig. 24. Triturating
surfaces of the molars except the last, which is broken away excepting the outer portion,
magnified three diameters. Grizzly Buttes. Dr. Carter.

Fig. 25. Triturating surfaces of the molar series, except the last, of the lower right side,
magnified three diameters. From another specimen loaned by Dr. Carter.

PLATE VI.
2

Figs. 26, 27. PARAMYS DELICATIOR :
Fig. 26. Left side lower jaw, with the second molar, natural size. Grizzly Buttes. Dr.
Carter. Fig. 27. Triturating surface of the second molar, magnified three diameters.
Figs. 28, 29. PARAMYS DELICATISSIMUS :
Fig. 28. Right side of lower jaw, with all the molars, natural size. Grizzly Buttes. Dr,
Carter. Fig. 29. Triturating surfaces of the molar series, magnified three diameters.

Fig. 30. Scruravus(?) Triturating surface of a lower left third molar, magnified eight diameters. From
a portion of the lower jaw obtained at Grizzly Buttes by Dr. Carter.
Figs. 31,32. Mysops MINIMUS:

Fig. 31. Right side of lower jaw, with third and fourth molars, magnified two diameters,

Fig. 32. Triturating surfaces of the teeth, magnified eight diameters. Dr. Carter.
Figs. 33-35. LOPHIOTHERIUM SYLVATICUM: :

Fig. 33. Portion of left side- of lower jaw, with last premolar and first and last molars,
natural size. Fig. 34. Triturating surfaces of the last premolar and first melar. Fig. 35.
Triturating surface of the last molar. Specimen-from Henry’s Fork of Green River.

Figs. 36, 37. NOTHARCTUS TENEBROSUS :

Fig. 36. Right side of lower jaw, with canine and all the molar series except the first pre-
molar, natural size. Fig. 37. The triturating surfaces of the molars, magnified two
diameters. Specimen from Black’s Fork of Green River.

Figs. 38, 39. HipPposyUS FOMOSUS (?)

Fig. 38. Triturating surface of a lower right second molar, magnified two diameters. -From
a jaw-fragment from near Fort Bridger. Dr. Carter.

Fig. 39. Triturating surface of a left lower first molar, magnified two diameters. From a
jaw-fragment obtained by Dr. Carter near Fort Bridger.

Fig. 40. HipposyUs ROBUSTIOR :
5 Triturating surface of a left lower second molar, magnified two diameters. From Henry’s
Fork of Green River. Professor Hayden.
Fig. 41. HIPPOSYUS FORMOSUS :

Triturating surfaces of the upper left first and second molars, magnified three diameters
Specimen from near Fort Bridger. Dr. Carter.

Fig. 42. HyRACHYUS NANUS: .

Triturating surfaces of the back two premolars, and the molars, magnified one and a half
diameters. Taken from the left side of the lower jaw of the same specimen represented
in Fig. 14, of Plate II. Specimen obtained by Dr. Corson at Grizzly Buttes.

Fig. 43. TROGOSUS VETULUS, probably Anchippodus : :
Right lower incisor, natural size. From near Fort Bridger. Dr. Carter.

Fig. 44. SINOPA RAPAX: -
Portion of left sidé of lower jaw, with last premolar and first molar, natural size. From
. Grizzly Buttes. Dr. Carter.
Fig. 45. SINOPA EXIMIA:
Portion of left side of the lower jaw, supposed to belong to a smaller species of the former,
uatural size. From Grizzly Buttes. Dr. Carter.
Fig. 46. PAL@ACODON VERUS:

Penultimate molar of the upper left side, magnified four diameters. From Lodge-pole trail.
Dr. Carter.

1-9. HYOPSODUS PAULUS.

10, 11.
12) 138.
14-17.

MICROSUS CUSPIDATUS

MICROSYOPS GRACILIS

18-22.

23-25.

26, 27

PARAMYS- DELICATUS,
. P. DELICATIOR.

28, 29.
30.
$1, 32.

33-35
36, 37

38, 39.

40.

T. SINCLAIR & SON , LITH. PHILADS

P DELICATISSIMUS. 41.
42. HYRACHYUS NANUS.
MYSOPS MINIMUS. 43. ANCHIPPODUS YVETULUB.
. LOPHIOTHERIUM SYLVATICUM. 44, SINOPA RAPAX.
. NOTHARCTUS TENEBROSUS. 46.

46. PALAAACODON VERUS

4% o
4 as
*
J
a

EXPLANATION OF PLATE VII. -

All the figures are of the natural size, except Fig. 10, which is reduced to one-half the diam-
eter of the original.

Figs. 1-5. MERYCOCHGRUS RUSTICUS. From specimens obtained on Sweetwater River, Wyoming, by
Professor Haydewn’s party iu 1870.

Fig. 1. Series of-upper molars of the right side, viewed on their triturating surfaces. The
last tooth had not entirely protruded, and in the first one the median enamel-pits are

_ nearly obliterated.

Fig. 2. Upper last premolar and molar of the left side, of the temporary series.

Fig. 3. Upper second and third premolars of the left side, of the permanent series. The trit-
urating surfaces but slightly worn.

Fig. 4. Outer view of the same teeth, in a small jaw-fragment.

Fig. 5. Symphysis of the lower jaw, with the four incisors on each side.

Pig. 6. MERYCOCHG@RUS PROPRIUS. First and second upper molars of the right side. From a specimen
obtained on the Niobrara River, by Professor Hayden, in 1857.

Figs. 7-11. OREODON SUPERBUS. From specimets discovered in Oregon by the Rev. Thomas Condon.

Fig. 7. Last lower molar of the right side, viewed on the triturating surface.

Fig. 8. First and part of the second molars, from the same jaw-fragment as the preceding
figure.

Fig. 9. The three lower premolars of the right side, viewed on their triturating surfaces.
From the same specimen as Fig. 16, Plate II.

Fig. 10. Upper view of the intermediate portion of the face, one-half the natural size.

Vig. 11. View of the inner surface of a lower canine, from the left side of a specimen of a
jaw, which lies with its outer facé imbedded in a hard mass of rock.

Fig. 12. OREODON CULBERTSONI. A series of upper true molars of the left side. Specimen discovered
: by Mr. Condon on John Day’s River, Oregon.
Figs. 13, 14. DICOTYLES PRISTINUS. Specimens in the Condon collection of Oregon fossils.
Fig. 13, Triturating surface of a lower penultimate molar.
Fig, 14. Outer view and view of the triturating surface of a lower last molar.
Fig. 15. ANCHITHERIUM Barrpr. An upper right molar. From the Condon collection.

Figs. 16,17. ANCHITHERIUM AGRESTE. From a specimen found on Red Rock Creek, one of the head
streams of the Jefferson Fork of the Missouri. Obtained by Professor Hayden in 1871.
Fig. 16. Lower last premolar and first molar of the left side.- Triturating surface much
worn.
Fig. 17. Last molar, from the same specimen of the jaw as the former.

Figs. 18, 19. FELIS AuGustus. Specimens discovered by Professor Hayden on the Loup Fork of the
Niobrara River, Nebraska.
Fig. 18. Portion of the right premaxillary, containing the second incisor, viewed in front.
Fig. 19. Upper sectorial molar of the left side, viewed externally.

Fig. 20. PATRIOFELIS ULTA (?) A premolar, probably of the upper jaw. Specimen found by Dr. Carter in
the vicinity of Fort Bridger, Wyoming.

Figs. 21-23. Teeth of a carnivore, undetermined. Obtained by Professor Hayden’s party on Henry’s
Fork of Green River, Wyoming. .
Fig. 21. Outer view of the crown of an anterior premolar. Fig. 22. Upper view of the same.

Fig. 23. Outer view of the crown of a canine tooth.

PLATE VII.

2

Figs. 24, 25. Raryocrros paciricus. A left inferior molar tooth, trom Bridger Creek, Oregon, belonging
to the Condon collection.
Fig. 24. View of the outer part of the crown. Fig. 25. Triturating surface of the same speci-
men,
Fig. 26. A canine tooth of an undetermined animal, probably of a large carnivore, but it may
be of an Elotherium-like pachyderm. ‘The specimen betongs to the Condon collection of
Oregon fossils, and is labeled “ Alkali Flats.” ;

Fig. 27. ELOTHERIUM IMPERATOR. A supposed incisor tooth, inner view. ° Specimen labeled “ Bridge
Creek,” and belonging to the Condon collection of Cregor fossils.

Figs. 28, 29. ELorumr1umM Morroni? An incisor tooth, obtained by Mr. Peirce, of Denver, twenty miles
? southeast from Cheyenne City, Wyoming.

Fig. 28. Inner view of the tooth. Fig. 29. Outer view of the same.

Fig. 30. Canine of an undetermined carnivore. It resembles the inferior canines of a bear, -:
but is more compressed. Specimen discovered by Professor Hayden on White River, Da-
kota, in 1866. The crown is compressed conical, with the inner surface defined in the
usual manner by acute borders. The fang exhibits a gibbous character. Length of crown
11 lines; breadth at base, 8 lines; thickness, 4} lines.

Plate VII.

§. Geological Survey of the Territories.

¥
"

1 SINCLAIR & SON.TH. PHIL?

EXPLANATION OF PLATE VIII.

‘Figures all one-half the diameter of nature.

Fig. 1. A lumbar vertebra of a crocodile. From Little Sandy River. Hayden’s collection of
- 1870. (Crocodilus Elliotti.)

Fig. 2. CROCODILUS APTUS:

A cervical vertebra, found on South Bitter Creek, Wyoming. :
Fig. 3. A first caudal vertebra of a crocodile. From Little Sandy River. Hayden’s collec- ~
tion of 1870.

Vigs. 4-6. Crocopitus ExLiotTri1. Hayden’s collection of 1870.

Fig. 4. Portion of the left maxillary, containing the fourth and fifth teeth of that bone
From the junction of Big Sandy and Green Rivers.

Fig. 5. Upper extremity of a left femur. From near Little Sandy River. .

Figs. 6,7. Upper view of a large portion of the skull. Found by H. W. Elliott, on Little
Sandy River.

Fig. 8. Left ramus of the lower jaw of a larger individual, or perhaps of a larger species,

’ Discovered in the vicinity of Fort Bridger by Dr. Joseph K. Corson, and presented by him
to the Academy of Natural Sciences of Philadelphia.

|

Plate VILL

ies

U. S. Geolowical Survey of the Territor

T. SINGLAIA & SON, PHILADELPHIA

Ye

CROCODILES.

EXPLANATION OF PLATE Ix.

All the figures half the natural size.

Fig. 1. TRIONYX GUTTATUS:

Portion of a carapace, consisting of the third to the sixth vertebral plates, inclusively,
together with parts of the contiguous costal plates. Specimen obtained at Church Buttes
during Professor Hayden’s exploration of 1868.

Figs. 2-6. EMYS WYOMINGENSIS :

Fig. 2. Portion of a carapace comprising the vertebral plates from the first to the eighth
inclusively, together with small portions of some of the contiguous costal plates.
Specimen, originally referred to Wmys Stevensonianus, obtained by Dr. Carter in the
vicinity of Fort Bridger, and presented by him to the Smithsonian Institution.

Fig. 3. Portion of a plastron, which accompanied the preceding specimen and was origi-
nally referred to 7. Stevensonianus.

Vig. 4. Anterior fragment of another plastron, accompanying the former two specimens, and
likewise referred to 7. Stevensonianus.

Fig. 5. An episternal, upon which the species Zmys wyomingensis was first noticed. Specimen
found by Dr. Carter near Fort Bridger.

Fig. 6. Central portion of a carapace, originally attributed to Hmys Haydeni. Specimen
obtained near Fort Bridger. Hayden’s collection.

Fig. 7 EMYS PETROLEI:

Two episternals from different individuals. Specimens from Hardin County, Texas.

aZIS % IMIOULHE SAWH 1
‘SISNWTONINOAM SAIN 9-6 | SOLVLLAD XANOIUL T

VIHd 301d ‘NOS @ HIVIONIS ‘1

_ Represents the nearly complete Stall of EMys1 oominGenste one- e-chalf t the natural size.

Pa 5 referred to a species with the name of Hmys Jeanesi. Specimen obtained fr Ol

or of Fort Bridger, during Professor Hayden’s exploration of 1870.
Fig. 1. View of the plastron. | at ae

ign: View of the carapace. . 2:

- » yi

a

ViIHdTaGWIIHd ‘NOS ® HIVIONIS “L

A” ‘SISNSFONTNOA AA SAN:

ee (Se Ske
“BOWMOgUIIE,yT, ey4 Jo LeArng peoiPoy
aA. ad Sim ae er J SL Ss

ef

op SO

ae

ate

EXPLANATION OF PLATE XI.

TESTUDO CORSONI:

Both specimens pertained to the same shell, and were originally described under the name
of Lmys Carteri. They were discovered near Fort Bridger by Dr. Carter, and presented to
the Academy of Philadelphia.

Fig. 1. The greater part of the plastron, its anterior extremity to the right, one-third the
natural size.

Fig. 2. The anterior intermediate portion of the carapace, its front to the left, one-half the
natural size.

Geological Survey of the Territories. — Plate XL

a cea ¥% ——— d * C “ ° T. SINCLAIR & SON. PHILADELPHIA.

: : EMYS CARTERI ~*~

EXPLANATION OF PLATE XII.

BaPTEMYS WYOMINGENSIS :
Figures one-third the natural size. Specimen discovered at Church Buttes, Wyoming, by
Mr. O. C. Smith, of Leverett, Massachusetts, while engaged in service of the Union Pacific
Railroad. It now belongs to the museum of the Academy of Natural Sciences of Phila-
delphia.
Fig. 1. View of the carapace.
Fig. 2. View of the sternum.

T. SINGLAIR & SON, PHILADELPHIA.

ti

RR — ee a et ea er ee
erse ‘

ay
4
P

fet

’

Kad

‘ak

, =

Fi

ang

‘erritor

7

of the

T 8. Geclepiedl Survey:

V3

BAPTEMYS WYOMINGENSIS.

EXPLANATION OF PLATE XIII.

BAENA ARENOSA:

Figures one-half the natural size.

Figs. 1,2. Specimen on which the genus and species were originally established. Dis-
covered at the junction of the Big Sandy and Green Rivers, Wyoming, during Professor
Hayden’s exploration of 1870.

Fig. 1. View of the carapace.

Fig. 2. View of the plastron, its anterior extremity lost.

Fig. 3. View of the plastron of another specimen, originally referred to a species with the
name of Baéna afinis. It was discovered by Dr. Carter at Church Buttes, and was pre-
sented by him to the Academy of Natural Sciences of Philadelphia.

%

“WIHd13GV IInd ‘NOS 8 YIVIONIS

TIX 9781

“L

SINIVAVY VNAVE

,
im

ee

y%

VSONHUVY VNEVE 61

‘SOILOJFUIOT, O44 JO foarng yeowWoToes “¢ . val :

EXPLANATION. OF PLATE XIV.

CHISTERNON UNDATUM, originally referred to Baéna nndata. Figures one-half the natural size. Speci-
men discovered in the vicinity of Fort Bridger by Dr. Carter, and presented by him to the
» Academy of Natural Sciences:
Fig. 1. View of the carapace ; the sutures scarcely visible. :
Fig. 2. View of the greater portion of the plastron, with the left border of the carapace.
The crucial suture of the plastron is visible, from which the genus received its name.

% WVWLVGNO VNuvd

~CWIHdT30V1IHd tNOS ® HIVIONIS “1.

-—— Ware fa rae” SEE OY

= i}

a ; es ; ‘saoguiag, ey yo Aesrng qeowWapoey 's Dol

Ae ie
Sue

EXPLANATION OF PLATE XV.

Figs. 1-5. BAWNA ARENOSA:

Fig. 1. Anterior extremity of the plastron, exhibiting the two pairs of gular scute areas.
From the same specimen as Fig. 3, cf Plate XIII. One-half the natural size.

Fig. 2. Anterior extremity of the plastron, fron another specimen found by Dr. Carter on
Henry’s Fork of Green River. The gular scute areas are larger, and the surface of the
plates is comparatively smooth. One-half the natural size. :

Fig. 3. From a specimen found by Dr. Corson at Grizzly Buttes. It is of greater proportion-
ate breadth than the former, and presents a want of symmetry in the gular seute areas.
One-half the natural size. 2 3

- Figs. 4,5. Of the natural size. From a young specimen obtained by Professor Hayden’s
party at the junction of Big Sandy and Green Rivers. It retains the sutures, which are
obliterated in the preceding mature specimens. ’

Fig. 4. Inferior view.

Fig. 5. Superior view, exhibiting the trident form of the entosternal bone.

Fig. 6. BAPTEMYS WYOMINGENSIS. One-half the natural size. A portion of the anterior extremity of
the plastron, from a specimen obtained by Professor Hayden’s party at Church Buttes. It
presents no distinction between gular and humeral scute areas.

Fig. 7. Testupo Corson. Anterior extremity of a plastron, one-half the natural size. From a specimen
discovered by Dr. Corson at Grizzly Buttes. -

Fig. 8. Supposed turtle egg, natural size. A frequent fossil of the indurated clays of the Bridger beds.
They are usually about the size of the specimen represented, though quite small ones are
also found, like that represented in Fig. 61, Plate XXXII. They have an onter calcareous
crust, and are filled with the same material as the imbedding matrix. Usually one end is
truncated and rough, as if the shell had been originally broken. Sometimes the truncated -
end appears covered with a low conical disk, resembling an operculum, as represented in
Figs. 60, 61, Plate XXXII.

Vig. 9. HYBEMYS ARENARIUS. A marginal plate, exhibiting the bosses on its outer extension. From
a specimen found by Professor Hayden’s party on Little Sandy Creek. Natural size.

Fig. 10. SfyLEMYS OREGONENSIS. A vertebral plate, one-half the natural size. From Crooked River,
Oregon.

Figs. 11-13. NorHosaurors occipuus. Three views of a vertebra, natural size, from a specimen ob-
tained by Professor Hayden on Moreau River.
Fig. 11. Side view of the centrum, exhibiting the sutural surface of the neural arch.
Fig. 12. Upper view of the same.
Fig. 13. View of the anterior end.

Figs. 14, 15. Santwa. Natural size. ;
Fig. 14. SanrwA Magor. Distal extremity of a humerus, fromm a specimen found by Dr.
Carter at the Lodge-pole trail, on Dry Creek, Wyoming.
Fig. 15. SANIWA ENSIDENS. Two dorsal vertebra as they lie in the matrix, inferior view,
from a specimen obtained near Grawger, Wyoming, during Professor Hayden’s exploration.

Figs. 16-18. ANnrroprmus. In the text, page 267, under the name of POICILOPLEURON VALENS. Figures
one-half the natural size. Three views of one-half of a vertebra, from Middle Park,
Colorado.
Fig. 16. End view, exhibiting the articular surface of the centrum.
Fig. 17. Side view.
Fig. 18. View of the broken surface of the vertebra, exhibiting the large areolew of the
interior of the centrum, inclosed by thick walls of compact substance.

1-5 BAENA ARENOSA.
6 BAPTEMYS. ¥.

7. TESTUDO CORSONI.
9. HYBEMYS.

Plate XV

X%

10 SPYLEMYS ¥
11-18. NOTHOSAUROPS.
14 15. SANIVA.

16-18 ANTRODEMUS. ¥

SINCLAIR & SON, PHILADELPHIA

EXPLANATION OF PLATE XVI.

All the figures of the natural size, except Figs. 13-17.

Figs. 1-6. ANOSTEIRA ORNATA:
Fig. 1. Portions.of the carapace.
Fig. 2. Portion of the same specimen, with portions of the plastron. Specimens collected
by Dr. Carter in the vicinity of Fort Bridger. :
Fig. 3. Inner view of three costals, from a portion of the same specimen as Fig. 1, exhibiting
the costal capitula.
Fig. 4. A third marginal plate from a larger individual. Dr. Carter. ba,

Fig. 5. A fourth marginal plate of the left-side of another individual. From Washakia ;
collected by James Stevenson. ‘ :
Fig. 6. Section of a pygal plate. From a specimen found by Professor Hayden at Church

Buttes. *
Fig. 7. Ilium of a turtle. Obtained at Grizzly Buttes by Dr. Carter.

Figs. 8,9. BARNA ARENOSA:
Fig. 8. [lium ofthe right side, outer view. Fig. 9. Sacrum, inferior view. Specimens ob-
tained from portions of the matrix, pertaining to the specimen of the shell represented in
Figs. 1, 2, Plate XIII. .
Fig. 10. Opisthocelian caudal vertebra of a turtle. From near Lodge-pole trail. Ar:
Carter. ;
Fig. 11. Fragment of a costal plate of a trionyx. From near Fort Bridger. Dr. Carter. *
Fig. 12. Fragment of a costal plate of a trionyx. From Little Sandy Creek. Professor
Hayden.
Figs. 13-17. Gryprosaurus. All magnified two diameters. .
Figs. 13-15. Osseous dermal plates of the body. Figs. 16,17. Plates of the head. From
Grizzly Buttes. Dr. Carter.

Figs. 18, 19. OLIGOSIMUS GRANDAVUS:
Fig. 18. Posterior view of a caudal vertebra. Fig. 19. Lateral view. Specimen obtained
by Professor Hayden’s party on Henry’s Fork of Green River.

Plate XVI

&
e
gs
A
Hl
oO
BH
(9)
oh
Sy
[o}
b
p
A
=)
ep)
4
tb
fo}
8 5
nD
Bb

LITH. PHILADA

T. SINCLAIR & SON

LE.
INN.

jab

OR

RIMBRA OF TU

WE

11,12. CCSTALS OF TRI
138-17. GLYPTOSAURUS.

1
+

1-6. ANOSTHIRA ORNATA.

7. ILIUM OF TURTLE

Ww
the

8,9 BAENA ARENOSA

18, 19. OLIGOSIMUS GRANDAVUS.

“

F,
es) eal
Pe vaee, AP aes

EXPLANATION OF PLATE XVII.

All the figures of the natural size, except Figs. 9, 10.

Fig. 1. CLupEA HUMILIS. From the original specimen obtained by Dr. John EH. Evans, on Green River,
in 1856.

Fig. 2. CLupEA ALTA. From the “ Petrified Fish Cut,” on the Union Pacific Railroad, near Green River.

Fig. 3. PETALODUS ALLEGHANIENSIS. Tooth, front view, from a specimen obtained by Messrs. Meek and
Hayden, in the upper carboniferous formation of Fort Riley, Kansas.

Figs. 4-6. CLADODUS OCCIDENTALIS. Tooth found by Messrs. Meek and Hayden, in the upper coal
measures of Manhattan, Kansas.
Fig. 4. Back view. Fig. 5. Section of the crown. Fig. 6. Bottom of the root.

Figs. 7, 8. PryCHODUS OCCIDENTALIS. Tooth discovered by Dr. John L. Le Conte, in the Cretaceous
formation east of Fort Hays, Kansas.
Fig. 7. Upper view. Fig. 8. Lateral view.

Figs. 9, 10. XIPHACTINUS AUDAX. A pectoral spine, one-half the natural size.
Fig. 9. Inferior view. Fig. 10. Superior view.

Figs. 11-17. MyLocyPRINUS ROBUSTUS. Pharyngeal bones, from Idaho, contained in the collection of

Professor J. S. Newberry.

Fig. 11. Inferior view of a left pharyngeal, containing the three intermediate teeth.

Fig. 12. Inferior view of a right pharyngeal, containing the anterior three teeth.

Fig. 13. Same view of a smaller left pharyngeal, with the posterior four teeth.

Fig. 14. Similar view of another specimen, with the anterior three teeth and the bases of
the posterior two teeth.

Fig. 15. Posterior view of a right pharyngeal of an old animal, with the second and fourth
teeth.

Fig. 16. Inner view of a right pharyngeal, with the posterior four teeth.

Fig. 17. Posterior view of the same specimen.

Figs. 18,19. ONCOBATIS PENTAGONUS. Dermal plate, from the Pliocene of Sinker Creek, Idaho.
Fig. 18. Upper view. Fig. 19. Lateral view.

Fig. 20. ENcHoDUS SHUMARDI. Dentary bone, natural size, but reversed in position. From the Cre-
‘taceous of Dakota.

Figs. 21, 22. CLADOCYCLUS OCCIDENTALIS. Two scales, natural size. Found with the preceding.

Figs. 23, 24. PHASGANODUS DiRUS. From Cannonball River, Dakota.

Fig. 23. A tooth of the natural size.
Fig. 24. Dentary bone, reduced one-third.

Fig. 25. XYSTRACANTHUS ARCUATUS. A dorsal spine, from Leavenworth, Kansas.

Fig. 26. HADROHYUS SUPREMUS:

The mutilated crown of an upper premolar tooth, natural size, seen on the triturating sur-
face. From the Miocene Tertiary of Oregon.

Plate XVII

U. S. Geological Survey of the Territories.

|

(SINCLAIR & SON LITH. PHIL

7

EXPLANATION OF PLATE XVIII.

All the figures are of the natural size except Figs. 51, 52.

Figs, 1-14. PrycHopus MortToni:

Figs. 15-18.

Figs. 19, 20.

Figs. 21-25.

a

Figs. 26-28.

Figs. 29-40.

Figs. 44, 45.

Tigs. 46-49,

Figs. 1, 2. Upper and posterior views of a large tooth from Kansas, obtained by Dr. George
M. Sternberg.

Figs. 3, 4. Upper and posterior views of another tooth, apparently from the same individual.

Figs. 5, 6. Upper and posterior views of another tooth from the same locality.

Figs. 7, 8. Upper and posterior views of another tooth from the same locality.

Figs. 9, 10. Upper and posterior views of another tooth from the same locality.

Figs. 11, 12. Upper and anterior views of a large tooth from near Columbus, Mississippi,
found by Dr. William Spillman.

Figs. 13, 14. Upper and posterior views of a tooth from Green County, Alabama, obtained
by Professor Joseph Jones.

PLYCHODUS OCCIDENTALIS. Specimen obtained near Fort Hays, Kansas, by Dr. John L.
Le Conte.

Figs. 15, 16. Upper and posterior views of a worn tooth.

Figs. 17, 18. Upper views of two small teeth.

PrycHopUS WHIPPLEYI. The specimen obtained in the Cretaceotis formation of Texas, by
Dr. Benjamin F. Shumard.

Fig. 19. Upper view ofa tooth. _ 7 =

Fig. 20. Posterior view of the same tooth.

OXYRHINA EXTENTA: : = }
Figs. 21-23. Views, external or anterior, of three teeth from the Cretaceous formation of
Kansas, obtained by Dr. George M. Sternberg.

Figs. 24, 25. External views of two teeth, from the Cretaceous formation near Colmmniynes
Mississippi, obtained by Dr. William Spillman.

OTODUS DIVARICATUS. The specimen from Texas, probably from a Cretaceous formation.
Loaned for examination by Dr. William Spillman.

Fig. 26. External or anterior view of the tooth.

Fig. 27. Lateral view reversed. : =

Fig. 28. Internal or posterior view.-+

GALEOCERDO FALCATUS. External views of teeth.

Figs. 29-31. Specimens from the Cretaceous of Kansas, collected by Dr. George M. Sternberg. -

Figs. 32-36. Specimens from the Cretaceous, near Columbus, Mississippi, collected by Dr.
William Spillman. ;

Figs. 37-40. Specimens from the Cretaceous, near Fort Hays, Kansas, collected by Dr. one
L. Le Conte.

Figs. 41, 42. Specimens from the Cretaceous of Texas, collected by Dr. Benjamin F, Shumard.

Fig. 43. Specimen from the chalk of Sussex, England.

.

LAMNA:

Fig. 44. External view of a tooth, from the Cretaceous, near Fort Hays, Kansas, found by Dr.
John L. Le Conte.

Fig. 45. External view of a similar but smaller tooth, from the chalk of Sussex, England.

LAMNA:

Figs. 46 , 47. Specimens from the Cretaceous of New Jersey. Fig. 46. Lateral view of a tooth.
Fig. 47, External view of another specimen.

Figs. 48, 49. Specimens from the Cretaceous, of Mississippi, collected by Dr. William Spill-
man. Fig. 43. Lateral view ofa tooth. Fig. 49. External view of another tooth.

Fig. 50. Outer view of a tooth. Specimen from the Cretaceous of Kansas, collected by Pro-
fessor Hayden.

. PALMOSYOPS PALUDOSUS. One-half the natural size.

Vig. 51. Side view of the face; from the same specimen as the teeth of Fie. 3, Plate IV.
Vig. 52. Lower jaw; repeated from the same specimen as Fig. 11, Plate V.

S. Geological Survey of the Bomitompe Plate XVIII.

Thos, Sinclair & Son, lith. Phila.” ~~

EXPLANATION OF PLATE XIX.

Figs, 1-4. PaLmosyors paLubDosus. All half size except Fig. 4.

Fig. 1. Front view of the left femur.

Fig. 2. Lower extremity of the right femur.

Fig. 3. Distal extremity of the right humerus.

Fig. 4. The right patella, inner view, natural size. Lodge-pole trail. Dr. Carter.

Fig. 5. Hyracuyus. An astragalus. Natural size.
Fig. 6. Distal extremity of left femur of Testudo niobrarensis, one-half the natural size.

Fig. 7. Distal extremity of right humerus of Testudo nebrascensis, from a young animal, half the natural
size.

Fig. 8. Distal extremity of the right humerus of Testudo niobrarensis, half the natural size.

Fig. 9. Portion of a carapace of Testudo nebrascensis, internal surface exhibiting the ridge of attachment
of the neural spines and the narrow costal capitula, natural size.

Fig. 10. Portion of right scapula of Testudo nebrascensis, back view, one-half the natural size.
Fig. 11. Sacral vertebre of Chisternon, undatum, inferior view, natural size.

Fig. 12. Lateral view of the same.

Fig. 13. Ungual phalanx of an undetermined reptile, one-half the natural size. See page 285.
Fig. 14. Dermal plate of Tylostews ornatus, one-half the natural size.

Figs. 15, 16. Pycnopus FaBA. Natural size.
Fig. 15. Portion of a left ramus of the lower jaw, with teeth. The specimen from the Creta-

ceous formation of Mississippi.
Fig. 16. Fragment of the left ramus of the lower jaw, with three teeth, from the greensand .
of Crosswicks, Burlington County, New Jersey.

Figs. 17-20. HADRODUS PRISCUS, natural size. Specimen belonging to Dr. William Spillman, of Colum-
bus, Mississippi, and found by him in the cretaceous formation of that State.
Fig. 17. Front view of a supposed premaxillary bone, with two teeth.
Fig. 18. Posterior view of the same, exhibiting at the sides the two reserve cavities for suc-
cessional teeth.
Fig. 19. Lateral view.
Fig. 20. Inferior view.

Figs. 21, 22. EumyLopus LAQuEATUS. Mandible two-thirds natural size. From the Cretaceous forma-
tion of Mississippi, discovered by Dr. William Spillman.
Fig. 21. Inner view ; specimen reversed. ;
Fig. 22. View of the upper or triturating surface, with the inner surface in perspective.

. §. Geological Survey of the Territories. Plate XIX.
SSIS ta gr dies , ;

Thos. Sinclair & Soa, lith, Phila.

EXPLANATION OF PLATE XX.

Fig. 1-7. PALHOSYOPS PALUDOSUS. Figures one-half size.
Fig. 1. Tibia of the right side, front view. From Grizzly Buttes. Hayden’s collection
of 1870.

Fig. 2. Calcaneum, upper view. Found by Dr. Corson on Smith’s Fork of Green River.

_ Fig. 3. Astragalus, upper view. Found by Dr. Carter near Millersville.
Fig. 4. Cuboid, seaphoid, and external cuneiform. From Church Buttes. Hayden’s collection.
Fig. 5. levered. Found by Dr. Corson near Fort Bridger.
Fig. 6. First phalanx. Found by Dr. Carter on Henry’s Fork of Green River.
Fig. 7. Second phalanx. Found by Dr. Carter near Fort Bridger.

Fig. 8. PALHOSYOPS MAJOR :

Portion of the right ramus of a lower jaw, one-half size. The specimen is somewhat swollen
and altered in character from disease, and is one of those upon which the species was first
indicated. Discovered by Dr. Carter at Grizzly Buttes.

Figs. 9-11. Merycocuasrus Rusticus. Natural size. From Hayden’s collection of the Sweetwater
River.
Fig. 9. Lower extremity of the right tibia, front view.
Fig. 10. Astragalus of the right side, upper view.
Fig. 11. Caleaneum of the right side, upper view.
Fig, 12. Merycocu@rus(?) Natural size.
Lower end of the right tibia of a smaller species than the preceding, with the specimens of
which it was found.
Fig. 13. Hieparton(?) Natural size.

Right cuneiform bone, upper view, of a small equine animal. Specimen found with the
remains of Merycocherus just indicated. :

Figs. 14-22. Remains from Texas, submitted to examination by Professor S. B. Buckley.
All of the natural size. _

Fig. 14. HIpPARION SPECIOSUM (?)

Last upper molar of the right side; view of the triturating surface. From Washington
County.

Fig. 15. Hipparion

(*)
A third or fourth upper molar of the left side. Found with the preceding specimen.
Fig. 16. PROTOHIPPUS PERDITUS (?)

A second or third upper molar of the right side. From Independence, Washington County.

Figs. 17, 18. PROTOHIPPUS PLACIDUS (?)
Fig. 17. A third or fourth upper molar of the right side. Found in association with the
specimens of Figs. 14, 15. :
Fig. 18. A first upper molar of the right side, probably of the same species as the former.
From Bastrop County.
Fig. 19. ANCHITHERIUM(?) AUSTRALE:
First upper molar of the right side. Found in association with the specimen of Fig. 16.

Fig, 20. PROTOHIPPUS :
A lower molar of the right side. From Navarro County.

PLATE XX.

Fig. 21. PROCAMELUS (?)
A first or second upper molar of the left side, view of the trituratine surface. Specimen
found in association with those of Fig. 14, 15, and 17, in Washington County.

Vig. 22. Astragalus of the left side, upper view, probably of the same species as the last, and found
with it.

Fig. 23. HIPPARION(?) PARVULUS
A coronary bene, or second phalanx, of the natural size. Found at Antelope, Nebraska.

Vig. 24. FrLis auGustus ?
Distal extremity of the right hnmerus, front view, one-half size. Specimen found on the
Niobrara River, by Professor Hayden.

Figs. 25,26. HyRACHYUS AGRARIUS. From a specimen obtained by Dr. Carter at Grizzly Buttes.
Natural size.
Fig. 25. Left ramus of the lower jaw, containing the back two premolars and the two suc-

ceeding molars. ;
Fig. 26. View of the triturating surface of the same teeth, with the addition of part of th

second premolar.

Thos, Sinclair & Son, lith. Phila.

_
‘
;

EXPLANATION OF PLATE XXII.

F -
Figs. 1-4. MASTODON OBSCURUS:

Last lower molar of the left side, natural size. Specimen discovered by Dr. Lorenzo G-
Yates, in Contra Costa County, California, and now in the museum of Amherst College.

Fig. 1. View of the triturating surface.

Fig. 2. Outer view of the same specimen.

Fig. 3. Fragment of a tusk, two-thirds the natural size, exhibiting the broad band of enamel
indicated by the darker shade. Specimen found by Dr. Yates in Stanislaus County, Cal-
ifornia, and belonging to Amherst College museum.

Fig. 4. Outline of the transverse section from the smaller end of the same specimen, of the
natural size.

U. S. Geological Survey of the Territories. sien

7. SINCLAIR & SOM YHILADEL) 14

1 2, MASTODON, CONTRA COSTA COUNTY, CAL. 4. MASTODON, STANISLAUS COUNTY, CAL.

get ca ee
nie es

ue

EXPLANATION OF PLATE XXII.

Fig. 1-4. MASTODON OBSCURUS:
Fragments of a lower jaw, from near Santa Fé, New Mexico, presented to the Smithsonian
Institution by W. F. M. Arny.
Fig. 1. Portion of the jaw containing the greater part of the last molar tooth. Fig. 2. Por-

tion of the symphysis. The two fragments placed in their relative position, and reduced
to one-sixth the natural size.

Fig. 3. Inferior view of the symphysial fragment, exhibiting exposed portions of the incis-
ors. One-fourth the natural size.

Fig 4. The last inferior molar, natural size, seen on the triturating surface. The back por-
tion, consisting of another division and the heel, are broken away. -

Figs. 5,6. MASTODON AMERICANUS. An anomalous molar tooth, natural size.

Fig. 5. View of the triturating surface.
Fig. 6. Side view.

Fig. 7. GRAPHIODON VINEARIUS. A tooth of the natural size. Specimen from the Miocene of Martha's
Vineyard, belonging to the museum of the Smithsonian Institution.

Plate ZXII,

WU. S&S. Geological Survey of the Termtones

eels

ges
SEEN

ee

—--—-~------ — =e

oe

x >on, hth. Phila.

iS

Thos, Sincla:

EXPLANATION OF PLATE XXIII.

All the figures of the natural size except Fig. 16, which is one-half size.

Figs. 1, 2. PALHOSYOPS MAJOR:
Fig. 1. The complete series of molar teeth of the left side of the lower jaw, except the first
premolar. The second and third premolars are reversed from those of the opposite side.
Specimen discovered by Dr. Carter in Dry Creek Caiion, forty miles from Fort Bridger.
Fig. 2. A series consisting of the molars and last two premolars contained in detached
fragments of a lower jaw. Specimens obtained by Dr. Carter on Dry Creek. The molars
are larger and more worn than in the preceding specimen. .

Figs. 3-6. PALZOSYOPS PALUDOSUS. Specimens upon which the species was originally established.
Hayden’s collection of 1870.
Fig. 3. A third lower premolar of the left side.
Fig. 4. A last lower premolar of the right side.
Fig. 5. A first lower molar of the left side.
Fig. 6. Anterior part of a second upper molar of the left side.

Figs. 7-11. PALZOSYOPS MAJOR. Specimens found by Dr. Corson in Dry Creek Cafion.
Fig. 7. The left upper canine tooth.
Fig. 8. The second upper premolar of the left side.
Fig. 9. The last upper premolar of the same side.
Fig. 10. The second upper molar of the same side.
Fig. 11. The last upper molar of the same side.

Fig. 12. PALHOSYOPS “MAJOR:
Series of premolars from the second to the last, inclusive, of the right side. From Dry
Creek. Dr. Carter.

Fig. 13. PALZosyors (LIMNOHYUS) LATICEPS (?)

A second upper molar of the right side. A comparatively smooth tooth. Specimen discov-
ered by Dr. Corson, in association with the large canine tooth of Figs. 1-3, Plate XXV.

Figs. 14-16. PALZOSYOPS MAJOR: ,
Fig. 14. A last lower molar of the right side. Contained in a jaw fragment obtained by
Dr. Carter at Dry Creek Cafion.
Fig. 15, An inferior incisor, lateral view, belonging to the same individual as the specimens
of Figs. 7-11. :
Fig. 16. Upper view of a cranium, one-half the natural size. The specimen discovered by
Dr. Carter at Dry Creek Cation.

U.S. Geological Survey of

the Terrtones

Plate XXL

PUAN.

OS IG OIZ'S,,

Thos. Sinclair & Son, lith. Phila.

ieth
+, OS See

mL 4

EXPLANATION OF PLATE XXIV.

Figs. 1-5. PALMOSYOPS MAJOR:

Fig. 1. View of a left side of a cranium, one-half the natural size. Specimen discovered by
Dr. Carter on the buttes of Dry Creek Cation.

Fig. 2. View of the left side of a crushed facial specimen, one-half the natural size. Speci-
men found by a Shoshone Indian, and brought to Dr. Carter.

Fig. 3. View of the triturating surface of a penultimate upper molar of the right side,
natural size. From the same skull as Fig. 1.

Fig. 4. Portion of the right ramus of the lower j jaw of the same animal, one-half he natural
size.

Fig. 5. An upper lateral incisor, natural size. Specimen found by Dr. Corson in the buttes
of Dry Creek Cafion.

Vigs. 6, 7. PALMHOSYOPS PALUDOSUS (?) Natural size.

Fig. 6. Fore part of the upper jaw, containing the first three premolars and part of the fang
of the canine.
Fig. 7. Triturating surfaces of the premolars.

Fig. 8. PALZOSYOPS HUMILIS:

A last upper molar of the left side, natural size. Found by Dr. Corson on the buttes of Dry
Creek Caiion.

Plate XXTV.

)U. S. Geological Survey of the Termtones.

t ;

‘ho? Sinclair & Son, Phala,

=

Tey My sulzh (©) SRG ONE! Sy,

‘

EXPLANATION .OF PLATE XXV.

UINTATHERIUM ROBUSTUM. All the specimens discovered by Drs. Corson and Carter at Dry

Creek Cafion. Natural size, except Figs. 8 and 11, which are one-half size.

Figs. 1-5. A supposed upper canine tooth. Discovered by Dr. Corson in company with a fragment of the

same tooth of the other side, the specimen represented in Figs. 13, 14, and the molar of
Palzeosyops represented in Fig. 13, Plate XXIII. eee referred. to a supposed car-
nivore, with the name of Uintamastix atrox.

Fig. 1. Outer view of the right canine. The restored outline of the lance-head-like point
is, perhaps, a little exage’erated.

Fig. 2. Inner view of the point of the same specimen.

Fig. 3. Front view.

Fig. 4. Outline of a transverse section of the lance-head-like point.

Fig. 5. Outline of a section near the base of the specimen.

Figs. 6-12. Specimens found together, with portions of the skull and other bones of the skeleton, ten

miles distant from the former. Discovered by Drs. Carter and Corson.

Fig. 6. Inner view of the last upper ‘molar of the right side.

Fig. 7. View of the triturating surface of the same tooth.

Fig. 8. Outer view of the same tooth inserted in a jaw-fragment, half the natural size.

Fig. 9. Inner view of the last lower molar of the right side.

Fig. 10. View of the triturating surface of the same tooth.

Fig. 11. Outer view of the lower-jaw fragment, containing ee same tooth, one-half tho
natural size.

Fig. 12. Triturating surface, much worn, of the first upper molar, of the right side.

. A supposed upper premolar of the same animal. Discovered by Dr. Corson in company with

the large canine tooth of Figs. 1-5.
Fig. 13. Inner view of the tooth.
Fig. 14. Triturating surface.

Plate “XY.

urves of the Terriomes

‘
NM

S. Geological &

Son, lith. Phila.

s. Sinclair

Tho

WIN AT EE Rl UM

EXPLANATION OF PLATE XXVI.

Figs. 1-8. UINTATHERIUM ROBUSTUM :

Fig. 1. View of the right side of a mutilated cranium, one-half the dineceren of nature. Spee-

imen upon which the genus was COC ieee Tisaaren ed by Dr. Carter about fifty miles
from Fort Bridger. j

Fig. 2. An atlas, of the same species. Inferior view, one-fourth the diameter. ~

Rig. 3. A right humerus. Found by Dr. Carter inthe same locality as the specimen of Fig. 1.
Anterior view, one-fourth the diameter.

Fig. 4. Proximal extremity of a femur, probably pertaining to a larger species of the same
genus, or perhaps to a larger variety. One-fourth the diameter.

Fig. 5. Distal extremity of another femur, probably of U. robustwm.. One-fourth the diameter.

Fig. 6. Calcaneum of the left side. Upper view, one-half size.

Figs. 7, 8. Astragalus, one-half size. ;

Fig. 7. Upper view. Fig. 8. Inferior view.

Figs. 9, 10. HyRACHYUS EXIMIUS:
Left lower penultimate molar tooth, natural size.
Fig. 9. Outer view. Fig. 10. Upper view.
Fig. 11. HyRaCHYUS NANUS:
Right ramus of the lower jaw, retaining the back four molar teeth. Natural size.

Plate XXVT

U. S. Geological Survey of the Territories.

Tae nenersig

——

lair & Son, Phila,

ISS UUN TA DEUS RG NES NEU NCI US)

Y Aestagi
tne ie

EXPLANATION OF PLATE XXVII.

Figs. 1, 2. HIpProsyus FORMOSUS:

Au upper molar tooth, probably the second true molar of the left side, magnified three
diameters.

Fig. 1. Outer view of the crown.

Fig. 2. View of the triturating surface.

Figs. 3, 4. WASHAKIUS INSIGNIS:
Fig. 3. Portion of the right ramus of the lower jaw, containing the last two molars, magni-
fied three diameters.
Fig. 4. View of the triturating surfaces of the teeth, magnified eight diameters.

Fig. 5. HYOPSODUS MINUSCULUS:

View of the triturating surfaces of the last premolar and the molars of the left side, magni- _
fied four diameters.

Figs. 6-10. UINTACYON EDAX: :

Fig. 6. Right side of the lower jaw, containing the intermediate three premolars, part of the
first molar, and the second molar, natural size.

Figs. 7-10. The teeth, magnified three diameters.

Fig. 7. Triturating surface of the second molar.
Fig. 8. Outer view of the same tooth.

Fig. 9. Upper view of the premolars.

Fig. 10. Outer view of the same.

+

Figs. 11-13. UINTACYON VORAX:
Fig. 11. Fragment of the left side of the lower jaw, containing part of the first molar and .
the second molar, natural size.
Fig. 12. Upper view of the second molar.
Fig. 13. Outer view of the second molar.

Figs. 14, 15. Mysors PRATERNUS :

Fig. 14. Right side of lower jaw, with the last three molars, magnified two diameters.
Fig. 15. View of the triturating surfaces of the molars, magnified eight diameters.

Figs. 16-18. PARAMYS DELICATIOR:

Fig. 16. Lower molar of the right side, the second or third of the series, seen on the tritu-
tating surface, magnified three diameters.

Fig. 17. Upper molars of the same animal, apparently the intermediate pair. Outer view,
magnified three diameters.

Fig. 18. View of the triturating surfaces of the same teeth, magnified three diameters.

Tigs. 19, 20. Microsyoes (?)
An upper molar tooth, magnified four times.
Fig. 19. Outer view.
Fig. 20. View of the triturating surface.

Figs, 21, 22. HyRACHYUS NANUS (?)
A last upper premolar, magnified two diameters.
Fig. 21. Outer view.
Fig. 22. View of the triturating surface.

PLATE XXVIL.
2

Fig. 23. Fragment of the left side of the lower jaw, containing two premolars, apparently the third and
fourth, of an undetermined carnivore, natural size. From the Bridger Eocene of Wyo-
ming.

Figs. 24, 25. MEGALOMERYX NIOBRARENSIS(?) A lower molar tooth, natural size. From the Tertiary of
L’Eau qui Court County, Nebraska. Specimen in the museum of Swarthmore College.

Fig. 24, Triturating surface.
Fig. 25. Outer view.

Figs. 26-29. PROCAMELUS VIRGINIENSIS. Natural size. Specimens from the Miocene of Virginia, and
belonging to Mr. C. M. Smith, of Richmond, Virginia.
Fig. 26. Outer view of the last lower molar of the right side.
Fig. 27. Triturating surface of the same. ;
Fig. 28. The last premolar and first molar of the right side, outer view.
Fig. 29. Triturating surfaces of the same.

Figs. 30-34. UINTATHERIUM ROBUSTUM: *
_ Fig. 30. Last upper molar of the right side, outer view, natural size.
Fig. 31: Last lower molar of the right side, outer view, natural size. :
Fig. 32. Portion of the left ramus of the lower jaw, one-half the natural size. Fig. 33. Mu-
tilated coronoid and condyle of the same specimen as the former. g ;
Fig. 34. Upper view of the atlas, from the same specimen as Fig. 2, Plate XXVI, one-fourth
the diameter of nature.

Fig. 35. SANIWA ENSIDENS. Tooth magnified eight diameters.

Figs. 36,37. SANIWA MAJOR:
Two dorsal vertebre, natural size.
Fig. 36. Inferior view.
Fig. 37. View of right side.

Figs. 38,39. CHAMELEO PRISTINUS. Fragment of the lower jaw, magnified three diameters.

Fig. 38. Outer view.

Fig. 39. Inner viey. '

Fig. 40. Undetermined tooth of a reptile, magnified two diameters. From the+ Bridger
Eocene formation of Wyoming. It may be the tooth of a crocodile or a lacertian. It is
an isolated specimen, partially imbedded in a greenish sandstone, with fresh-water shells. _
The crown is compressed mammillary, and strongly striate, from an acute-bordered summit.

Geclogical Survey of the Territories. 2 Plate XVI.

Th Sinclair & Son, Plula

EXPLANATION OF PLATE XXVIII.

Figs. 1,2. UINTATHERIUM ROBUSTUM :

Fig. 1. Outline taken from Professor Marsh’s Fig. 1, Plate II, of Dinoceras mirabilis, in the
Am. Jour. Science, 1873, enlarged so as to accord with one-sixth of the size of the frag-
ments introduced in the figure, which correspond with those of Figs. 1 and 8, Plate XXV,
and Fig. 1, Plate XX VI.

Fig. 2. View of the base of the cranial specimen also represented in Fig. 1, Plate XXVI.
One-sixth the diameter of nature.

Fig. 3. Large osseous protuberance, one-half the size of nature, resembling the similar
osseous protuberances of the specimen of Megacerops, represented in Wigs. 2,3, Plate 1.
The specimen is from the Mauvaises Terres of White River, Dakota, and was originally
suspected to belong to Ditanotherium.

Figs. 4-8. BISON LATIFRONS:

Figs. 4,5. Cranium from Pilarcitos Valley, California, discovered by Messrs. Calvin and
Wilfred Brown, and presented to the Academy of Natural Sciences of Philadelphia. One-
fifth the natural size.

Tig. 4, Upper view. Tig. 5. Posterior view.

: Figs. 6,7. The second and last upper molars seen on their triturating surfaces. Natural size.
Specimens from California, belonging to Wabash College, Indiana.

Vig. 8. An upper second molar of the left side, considerably worn, and seen on its triturat-

ing surface, Natural size. FWrom Luzerne County, Pennsylvania,

Fig. 9. MASTODON AMERICANUS:
A first lower prefodlar of the right side, natural size. Found with the preceding.

Geological Survey of the Territories. é j
gic vey lerritories : ‘i Plate, XXVIII.

/
on--4-~-----"" / 7

in

, Th Simelair& Son, hth. Vinla.

EXPLANATION OF PLATE XXIX.

All the figures one-half the natural size.

Fig. 1. TRIONYX UINTAENSIS :
The nearly entire carapace or upper shield, partially represented. Specimen discovered by
Major Robert 8. La Motte, in the buttes of Dry Creek, ten miles from Fort Bridger, and
presented by him to the Academy of Natural Sciences of Philadelphia. :

Figs. 2-4. TEstTUDO CoRSONI:
Specimens discovered by Dr. Joseph K. Corson, in association with portions of the plastron,
and the specimen of the carapace represented in Fig. 1, Plate XXX.
Fig. 2. Anterior view of the proximal extremity of the right humerus.
Fig. 3. Outer view of the same specimen.
Fig. 4. Distal extremity of the right femur, front view.

Fig. 5. PALHOSYOPS PALUDOSUS:
Femur of the left side, anterior view. Specimen obtained by Dr. Carter on Grizzly Buttes.

U.S. Geological Survev of the Territories.

Teen SS DO ee ey ee See

Plate. XXiX.

Th®? Sinclair & Son, Pinia

1 TRIONYX UINIAENSIS. 2-4 TESTUDO CORSONI. 5.PALAEOSYOPS PALUDOSUS.

iy.

he

EXPLANATION OF PLATE XXX.

*

.

Figs. 1-4. Testupo CorRsontr:

Fig. 1. Intermediate portion of the carapace, one-half the natural size, exhibiting the series
of vertebral plates, from the first to the eighth and part of the ninth, and contiguous por-
tions of the costal plates. Specimen discovered by Dr. Joseph K. Corson on the buttes of
Dry Creek, and presented by him to the Academy of Philadelphia.

Fig. 2. Plastron, or lower shield, one-third the natural size. Specimen discovered by Dr.
Corson on Grizzly Buttes, and presented to the Academy. ;

Fig. 3. Anterior process of another plastron, one-half the natural’size. From a specimen
discovered by Dr. Corson in the same locality as the last.

Fig. 4. Anterior process of a nearly complete plastron, one-half the natural size. From a
specimen discovered by Mrs. Dr. Carter on the buttes of Dry Creek, and presented by her
to the Academy of Philadelphia. ;

Fig. 5. CLADOCYCLUS OCCIDENTALAS :
Large scale, imbedded in a lead-colored caleareous shale, natural size. Specimen obtained
by Professor Hayden from the Cretaceous formation of Sage Creek, Dakota.

U.S. Geological Survey of the Territories Plate XXX,

i
‘
'
!
1
|
A
H
'
a
'
!
t

The? Sinclair & Son, Pinta,

{-4 TESTUDO CORSONI. 5. COLAIDOCSEGIRIUS:

EXPLANATION OF PLATE XXXII.

Fig. 1. Restored skull of Palwosyops. The cranium and face are introduced from the specimens of
Figs. 1, 2, Plate XXIV, and Fig. 51, Plate XVIII; and the lower jaw from the specimen of
Fig. 52 of the latter plate, and Fig. 4, Plate XXIV. About half the natural size of the
skull of P. paludosus.

Fig. 2. CANIS INDIANENSIS :
Right ramus of the lower jaw, one-half the natural size. Specimen from San Leandro, Cali-
fornia. Discovered by Dr. Lorenzo G. Yates, and now in the museum of Wabash College,
Crawfordsville, Indiana. ; s

Fig. 3. FELIS IMPERIALIS :
Fore part of the upper jaw, with the second premolar, one-half the natural size. Accom-
panying the preceding specimen.
Fig. 4. LUTRA PISCINARIA:

Tibia of the right side, two-thirds the natural size. From Sinker Creek, Idaho, and belong-
ing to the Smithsonian Institution. :

Plate XXX1.

Thos Sinclair & Son, lith. Phila.

U. S. Geological Survey of the Territories

EXPLANATION OF PLATE XXXII.

All the figures of the natural size.

Figs. 1-6. AmIA (PROTAMIA) UINTAENSIS:
Fig. 1. Centrum of a dorsal vertebra, anterior view. Fig. 2. View of the same beneath.
From Dry Creek Cafion.
Fig. 3. Centrum of an atlas, anterior view. Fig. 4. Inferior view of the same. From Dry
Creek Caiion.
Fig. 5. A series of three posterior dorsal centra, inferior view. From Dry Creek Caiion.
Fig. 6. Basi occipital, posterior view. Fig. 6a. Inferior view of the same. From Dry Creek.

Figs. 7-11. AMIA (PROTAMIA) MEDIA:
~ Fig. 7. Centrum of a dorsal vertebra, upper view. Fig.8. Posterior view. Fig. 9. Inferior
view. Junction of Sandy and Green Rivers.
Fig. 10. Cenirum of a posterior dorsal vertebra, back viow. Fig. 11. Inferior view. Dry
Creek.

Figs. 12, 13. LEPIDOSTEUS NOTABILIS:
Fig. 12. Centrum of a dorsal vertebra, inferior view. Fig. 13. Posterior view. From near
Washakie, Wyoming.
Figs. 14, 15. LepIposTEUS ATROX : :
Fig. 14. Centrum of an anterior dorsal vertebra, inferior view. Fig. 15. Posterior view.
From the junction of Big Sandy and Green Rivers.
Figs. 16, 17. LrpIposTEvS (?) See page 190.

Fig. 16. Centrum of a posterior dorsal vertebra, seen beneath.
Fig. 17. Posterior view of the same.

Fig. 18. LErmosTEUS SIMPLEX:
The basi occipital and three vertebral centra, seen beneath. From near Washakie Station,
Wyoming.
Figs. 19-22. HyPAMIA ELEGANS. A vertebral centrum. From Dry Creek.

Fig. 19. Upper view. Fig. 20. Lateral view. Fig. 21. Posterior view. Fig. 22. Inferior
view. °

Figs. 23, 24. Amira (PROTAMIA) GRACcrLIS. A centrum from near the middle of the dorsal series. Henry’s
Fork of Green River, Wyoming.

Fig. 23. Posterior view. Fig. 24. Inferior view.

Fig. 25. LEPIDOSTEUS (?)
Fragment of the right dentary bone. See page 190.

Fig. 26. LEPIDOSTEUS SIMPLEX. A tooth. See page 191.

Figs. 27-30. LEPIDOSTEUS

(?) Scales from Big Sandy and Green River.

Figs. 31-34. LEPIDOSTEUS SIMPLEX. Scales. From near Washakie Station. See page 191.
Figs. 35-38. LEPrIDOSTEUS. Scales. Little Sandy Creek. See page 192.

Figs. 39-42. LEPIDOSTEUS. Scales. Near Fort Bridger.

Fig. 43. LeprmposTeus. Scale. See page 192.

PLATE XXXII.

Figs

Figs

Figs

Figs

. 44-46.

. 47-51.

. 2, 53.

. Bd, 55.

. 56, 57.

PIMELODUS ANTIQUUS:
Figs. 44, 45. Fragments of pectoral spines.
Fig. 46. Portion of a dentary bone, seen from beneath.

PHAREODUS ACUTUS. Jaw fragments, from the junction of Big Sandy and Green Rivers,
Wyoming. E

Fig. 47. Portion of the right premaxillary.

Fig. 48. Portion of left premaxillary.

Fig. 49. Portion of right dentary.

Fig. 50. Portion of left dentary.

Fig. 51. Portion of a maxillary.

TRYGON (?). Caudal spine of a Ray, From the Miocene of Virginia. Fig. 52. Anterior view
of basal portion’of the spine. Fig.53. Section of thesame. Belonging to Mr. C. M. Smith.

MYLIOBATES (?). Caudal spine. Found with the preceding.

Fig. 54. Anterior face of basal portion.
Tig. 55. Section of the same.

PROTAUTOGA CONIDENS :

Portions of premaxillaries, with teeth, from tbe Miocene of Virginia. Belonging to C. M.
Smith. :

Fig. 56. Fragment of the left premaxillary, containing the first tooth.

Fig. 57. Right premaxillary, inner view, exhibiting, besides the outer row of large teeth, an
inner row of small ones.

Fig. 58. ACIPENSER ORNATUS:

A dermal plate. From the Miocene of Virginia.’ Belonging to Mr. C. M. Smith.

Fig. 59. ASTERACANTHUS SIDERIUS:

Basal portion of an ichthyodorulite, lateral view.

Plate XXXII.

. S. Geological Survey of the Territories.

SRS Sees

os

‘Lh? Sinclair & Son, Pina.

ba a

via ve Gy

EXPLANATION OF PLATE XXXIII.

All the figures of the natural size.

Figs. 1, 2. EQUUS OCCIDENTALIS:
Fig. 1. The anterior four upper molars of the left side, seen on their triturating surfaces.
The teeth are contained in a jaw-fragment, obtained by Dr. George H. Horn from an
asphaltum deposit near Buena Vista Lake, California. Specimen in the museum of the
Academy of Philadelphia.
Fig. 2. A second upper left molar, seen on the triturating surface. From Tuolumne County
California.

Figs. 3-18. EQUUS MAJOR: a :

Figs. 3, 4. A first upper molar tooth of the right side. Fig. 3. Outer view. Fig. 4. Tritu-
rating surface. Specimen from Hardin County, Texas. ‘

Figs. 5, 6. A first upper molar of the right side. Fig. 5. Outer view. Fig. 6. Triturating
surface. ~ Krom Illinois Bluffs, Missouri.

Figs. 7, 8. A last upper molar of the right side. Fig. 7. Outer view. Fig. 8. Triturating
surface. From Hardin County, Texas. a"

Fig. 9. A last lower molar of the left side, view of the triturating surface. Found with the
last.

Fig. 10. A fifth lower molar of the left side, triturating surface. Found with the last.

Fig. 11. A second or third upper molar of the right side, triturating Surface. From Galves-
ton Bay, Texas. Presented to the Academy by Dr. Thomas H. Streets.

Tig. 12. A first lower temporary molar, triturating surface. From Hardin County, Texas.

Fig. 18. An upper last temporary molar of the left side. Found with the last.

Fig. 14. An upper second or third molar of the left side. From the “phosphate beds” of
Ashley River, South Carolina.

Fig. 15. A second or third lower molar of the right side. From the same locality as the last.

Fig. 16. An upper second or third molar of the right side. From Luzerne County, Pennsyl-
vania.

Fig. 17. A second lower molar of the left side. Found with the last.

Fig. 18. An upper fourth or fifth molar of the left side. From Texas.

Fig. 19. Equus. Portion of an upper molar of the left side of an undetermined species. From the lignite
beds of Shoalwater Bay, Washington Territory.

Figs. 20, 21. Two phalanges of undetermined animals, both found, in association with the equine and
other remains, in an asphaltum deposit in Hardin County, Texas. They are both satu-
rated with bitumen. Fig. 20. Lateral view of the specimen. Fig. 21. Inferior view of
the second specimen.

Plate XXXII.

U.S. seclogieal Survey of the Territoriéss

air & Son, lith. Phila

a]

ancl

UAE'S

EXPLANATION OF PLATE XXXIV.

All the figures two-thirds the size of nature except Figs. 12-22, which are of the natural
size. :

Figs. 1 to 5 and 10. CLIDASTES INTERMEDIUS. From the Cretaceous of Alabama. Museum of the Acad-

emy of Natural Sciences.

Fig. 1. Outer view of the fore part of the left mandible.

Fig. 2. Back part of the right mandible, outer view reversed.

Fig. 4. Reserve tooth, concealed in the excavated base of the last of the series in the speci-
men of Fig. 1, seen from within. ;

Fig. 5. Reserve tooth, concealed in the excavated base ef the second of the series of the same
specimen, seen from within.

Figs. 6 to 9 and 11. Cripastes arrris. From the Smoky Hill River, of Kansas. Belonging to the mu-

Fig. 10

Fig. 11.

Fig. 12

seum of the Smithsonian Institution.

Fig. 6. Outer view of the left mandible.

Fig. 7. Inner view of back part of the right mandible, exhibiting the glenoid articulation.
Fig. 8. Upper view of two fragments of the cranium. .

Fig. 9. The basi-sphenoid bone.

c=)

. C. InrErMepIvs. The axis seen below and with the fore part downward.
C. arrrnis. The left humerus, posterior view.

. LESTOSAURUS CORYPHZUS:

Greater portion of a palate-bone, with teeth, natural size. From the Smoky Hill River,
Kansas.

Fig. 13. CLIDASTES AFFINIS. Tooth contained within a jaw-fragment. From Smoky Hill River, Kansas.

Fig. 14

. Crown of a similar tooth. From L’Eau qui Court County, Nebraska. It is compressed, conical,

curved, with acute borders and smooth surfaces. Fig. 15. Section of the same tooth.

Figs. 16-22. Teeth of mosasauroids, natural size, together with the preceding specimen from L’Eau qui

Court County, Nebraska. Presented to Swarthmore College by George S. Truman.

Fig. 16. Crown of a shed tooth, with striated enamel. Fig. 17. Transverse section of the
same, at the base. :
Fig. 18. Shed crown of a large tooth, with striated enamel, anterior view.

Fig. 19. Shed crown of a tooth, with distinct subdivisional planes. .Fig. 20. Outlines of sec-
tions of the same at the base and above the base.
Fig. 21. Crown of another shed tooth, intermediate in character with the two preceding.

Fig. 22. Outline of a section of the same at the base.

t
!
;

Plate XXXIV.

Thos Sinclair & Son

¥ ut

th. 1

1

EXPLANATION OF PLATE XXXYV.

All the figures one-half the natural size except Fig. 14, which is of the natural size.

Figs. ‘1-11. TynosauRUS DYSPELOR. Specimens from the Cretaceous of Nes Mexico, and belonging to

Figs. 12, 13.

the Suuchsomian Institution.

Fig. 1. Aenean ball of a posterior dorsal centrum.
Fig. 2,3. The same of two other specimens, exhibiting a successive increase of compression

from above downward.

‘Fig. . Articular ball of a caud&l.centrum.

Fig. 5. Left lateral view of the same.

Fig. 3 Articular ball of a more posterior caudal centrum.

Fig. 7. Left lateral view of the same specimen, exhibiting the reduction in the size of the
diapophysis.

Fig. 8. Left lateral view of a more posterior caudal vertebra, devoid of diapophyses.

Fig. 9. Supposed femur, posterior view.

Fig. 10. Supposed fibula.

Fig. 11. Supposed tibia.

fC}

TYLOSAURUS PRORIGER. Specimens from the Cretaceous of Kansas, belonging to the
Smithsonian Institution.

Fig. 12. Extremity of the snout, or of the premaxillary.

Fig. 13. Posterior articular surface of the left splenial bone of the lower jaw.

Fig. 14. Tooth of a mosasauroid, natural size, from the Cretaceous of L’Eau qui Court
County, Nebraska. The crown is compressed, conical, with acute borders and smooth sur-
faces. The base is compressed oval, and it exhibits on its inner side a small concavity for
the accommodation of a successor.

US, Geological Survey of the Territories. : Plate XXKY,

Lom,

ecu y

thes Smela & Son, lith . Phila

EXPLANATION OF PLATE XXXVI.

Figs. 1-3. TYLOSAURUS PRORIGER:
Figs. 1,2. A caudal vertebra, one-half the natural size. From the Cretaceous of Kansas.
Smithsonian Institution.

Fig.
Fig.

1. Left lateral view. Fig. 2. Posterior view.
3. A tooth which accompanied the former specimen, lateral view, natural size.

Figs. 4-14. LESTOSAURUS CORYPHUS. All the figures one-half the natural size. From the Cretaceous
of Kansas. Museum of the Smithsonian Institution.

Fig.

4, Inferior view of. a dorsal vertebra. Within the position of the right zygapophysis a

rudimental zygosphene is observed.

Fig.
Fig.
Fig.
Fig.
Fig.
Fig.
Fig.
Fig.
Fig.
Fig.

5. Inferior view of a second specimen.

6. Inferior view of the body of a cervical vertebra.

7. Right lateral view of another cervical vertebra.

8. Left lateral view of an anterior caudal vertebra.

9. Same view of a more posterior SUS EME.

10. Posterior view of the same.

11. Left lateral view of the bodies of two posterior vertebra.

12. Posterior view of the second of the latter. 3
13. Limb-bone, probably an ulna or a fibula.

14. Probably a radius or a tibia.

Fig. 15. Mosasaurvus:
A caudal vertebra, from L’Hau qui Court County, Nebraska. Museum of Swarthmore Col-
lege. Presented by George S. Truman. Inferior view one-half the natural size.

Fig. 16. TyLosAuRUS DysPELOR. Inferior view of the same caudal centrum as that of Fig. 4, of the
preceding plate. Half the natural size.
Figs. 17-21. Limb-bones of a turtle, from the Cretaceous of Smoky Hill River, Kansas. -
Smithsonian Institution. Three-fourths the natural size.

Fig.
Fig.
Fig.

17. Upper extremity of the right humerus, anterior view.
18. The right femur, anterior view.
19. Portion of a left scapula, inverted in position. The broken process to the left is

the precoracoid. Posterior view.
Fig. 20. Portion of the coracoid. The articular surface at the upper end is for the scapula.

Fig.

21. Portion of an undetermined limb-bone.

Plate XXXYT.

Thes Sinclair & Son, ith . Phila.

Hy ote
1

ne Nes
= Millers ae
ait

aes!
MS cay

ul

A ty
KE) | Bee

EXPLANATION OF PLATE XXXVILI.

' i
- Cee
Os

Specimens from the Quaternary of California, and belonging to the cabinet of Wabash
College, Crawfordsville, Indiana. :
Fig. 1. Outer view of the series of lower molar teeth of the left side, one-half the natural
size.
Fig. 2. Triturating surfaces of the same series, natural size.
< Fig. 3. A second upper molar of the left side, view of the triturating surface, natural size.

Figs. 1-3. AUCHENIA HESTERNA:

Fig. 4. Bison:

Last lower molar of the left side, triturating surface, natural size. Specimen found with
remains of Megalonyx Jefferson, in Illinois.

Fig. 5. ACRODUS HUMILIS. Magnified one and a half times. View of the triturating surface of a tooth.
From the Cretaceous of New Jersey.

Figs. 6-12. EDAPHODON MIRIFICUS. One-half the natural size. Specimens from the Cretaceous of New
Jersey, and belonging to the cabinet of Rutgers College, New Brunswick, New Jersey.
Fig. 6, The mandibles seen on their oral surface.
Fig. 7. Outer view of the left mandible.
Fig. 8. Inner view of the left mandible.
Fig. 9. Posterior outline of the same, with outlines of the dental columns.
Fig. 10. The maxille seen on their palatine or oral surface.
Fig. 11. Outer view of the left maxilla.
Fig. 12. Posterior outline of the same, with outlines of the dental columns.

Figs. 13,14. KuMyLODUS LAQUEATUS:
Left lower maxilla, one-half the natural size.
' Fig. 13. Oral surface, exhibiting the dental tubercle.

Fig. 14. Outer view. Specimen from the Cretaceous of Mississippi, and discovered by Dr.
William Spillman.

Fig. 15. PONTOBASILEUS TUBERCULATUS. Fragment of a tooth, with restored outline, natural size.

Figs. 16,17. MANaTus InorNnatUS. A lower right molar, natural size. From the phosphate beds of
Ashley River, South Carolina.

Fig. 16. Upper view.

Fig. 17. Outer view.

Figs. 18,19. PycNopDUS ROBUSTUS. Tooth of the natural size.
Fig. 18. Triturating surface.
Fig. 19. Posterior view. Specimen from the Cretaéeous of New Jersey.

U. S Geological Survey of the Territories, Plate XXXVII

ee
@

—

Th Sinclair & Son, Phila,

7

i i rate,
‘ied

he
oe

a HE GLY BE BE career a
... wi