ei 
PETERSON: DESCRIPTION OF NEW RODENTS 147 
XX., pp. 207-270, 1904) has the same general shape as the skull of S. fossor, but 
the latter differs in having a relatively greater interorbital constriction ; the dias- 
tema in front of the cheek-teeth is more highly arched; the palate is longer, and 
the basioccipital is not excavated. In S. fossor the ascending ramus of the mandible 
is not so vertical as that of S. pansus. 
MEASUREMENTS. 
Skull. 
Type. Coty pe. 
Greatest length mm. 76 mm. 
Greatest width G6 62 OG 
Greatest height, measured at m* to top of anterior part of sagittal crest ............. 30 es 
Greatest width of occiput at external auditory meatus ..................0ceceee eee Pheer 48 te 48 5 
Greatestawidthrofemuzzletantenonlys-sc-c.-cesocsescseasterorectnetectan tect tere ee anaes 12 a 15 “ 
Width of interorbital constriction “ 
ILE EANN. OL TACT Joconéonddo00005 008008d095de0ccb0 caso qn adadopcaqdooa0cecdoe oxecCoooDcEbOSoddboododcHoNeN we 
Length of sagittal crest from union of temporal ridges to occiput ... 28 i 
IRICEN OP CRED MB-codco: osesec000%= oosco6 onsocooq.bnqUdenCoODOEnEd Daas LeBsaoBOD bodeac aooceSnaedeeass 22 Oe 
Antero posterior diameter of otic bulla........0. .......ccccsecesecoees cescecsescceveceseses 1B & behoulet at 
Transverse diameter including tube and external auditory meatus...................+: 24 ss 
Hxtremenwidthrof.occipitalecondylestcsssessarcsessseecce cere eee eee eee 16 tt 
Spacesbebweenhncisorsjandeparnccan-cvesssscessdiccessereccetcr rece ee ateeec eestor eee eee 27 se 30 ue 
Space from m# to and including condyle ..............:ceccccsecececsae cececeeeeeeeeecereeees 28 se 
Width of palate at p4 Boa a 4 : 
Wild thyotmpalatey bien seerececclncc-ccescelecsees ste sseeceteae ee assee es eaeece eae eater Enotes 6 a 
Superior Dentition. 
Length of incisor from the alveolar border to the cutting point..................---..6+- 21 ug 21 Oe 
Antero-posterior diameter of incisor Baier Bile ot 
Transverse diameter of incisor.......... 5 be 5 au 
Antero-posterior diameter of grinding teeth........-....2..:2e.seceee seen ee eee eee eee eee rete 14 ee 14 ag 
Antero-posterior GIETINGTIOR OF 7124 ceagocaascoonseessiooosanooxcaccannooDoGuGoaccdseadonSteds dooDaDeKC 4 oe 4 Be 
Transverse diameter Of p+..............2.ccecceeccceeceecenereescr nese eceesecsesscecceeeeseceasees 4 ey 4 - 
Antero-posterior diameter of m+ 3 ae Si aes 
Transverse diameter Of mee... 2.2... -.c...-cncnnnscermerees oonndeees deceereesencereeesiserencrcseers 4 SF 4 oS 
Antero-posterior diameter of m2 3 ‘ 3 
Transverse diameter of m2 30 ** any 
Antero-posterior diameter of m+ Ph 8 3 ue 
Transverse! diameter! Of M2... cs. cecece cscs eer encissescrec comet roms oeneleserisrtiecceisdcssis-saeee= Pi) Oe 3 se 
Mandible. 
Greatest length of mandible including incisor.................. = 64 3 
Length of mandible from process on angle to incisor —alveolar border.... ot 54 “ 
Greatest depth from angle to top of coronoid process...-......--.2-+:e-sseeeeeeeeeeeeee sees ue 
TOYO IN 5 CUE SHOE pecocecac caogcceodoedeo DOLE cacorOnSo-aa care SoScenE pads sooaScaeneraacHoCAcaN coadoNecENaasIG: os 12 st 
“ce 16 “cc 
Height of coronoid’ process.........022.0.00+-c-ssercensecrnsere seecaretcencvereatserccrrerccseseas Way O56 “0 
Antero-posterior diameter Of COndyle...........-.:-esescecnneeececereneeeecesseneeerceseeeeeeees Gira ee @G 
