A MK.MOIK Ul’ON THE GENUS 
ill TehnaloUieriiini and tlu- smaller species oi Paiceosyops. The chacraters 
oftla- rvtiTiial Inls-s and Imtlivsses in tliis species offer a sure means of distinguish- 
i„g it Inmi tl...s.- of the s|H-cies of Tehnatothermm. 
'riie pn-s«-nce of tlie intermediate conules is very characteristic of this species, 
and ii|H.n earli iipia-r true molar a protocoiiule is always present. This lohiile in 
Palteosyops piiltuhsus is ver\- larga- and prominent, especially on superior molars 1 and 
*J. In tin- last iipia-r molar the protocoiiule is much smaller, it being largest on 
molar I and d«*<-i-easing |M)steriorly in size. There is no metaconule on molars 1 and 
•J. although this roiinle may Ik- jnv.sent on molar 3. In the collection of the Prince- 
ton .Miih-iiiii there is a very inteivsting hmt upper molar, (Plate 12, fig. 18), which 
ha.H Isith the intermediate coiinles strongly developed, especially the protocoiiule, 
whieh is with the anterior cingulum by a prominent prolongation. In 
this molar the ext«-rnal Vs are rather irregular in form, the anterior one having 
a iiroiiiineiit iiH-«lian fold. 'I'liese characters are more primitive than those found in 
a tvpieal molar of this siK-cies and point to Lambdol/ierium, where the external 
lols-s «if tin- molars an- not as highly differentiated as in Palceosyops. The external 
fare of tin- true molars is totally devoid of a cingulum, a character which readily dis- 
tinguishes this s|H-eies from P. minor. 
'Pile pn-senee of ail (-xteriial cingulum is a prominent character in the denti- 
tion «if /*. minor. 'Pin- anterior (-ingulum is very strongly developed in this species; 
it t’orius a v»-ry pnimiiient transverse ridge, distinct from the protocoiiule of the 
molar. Is-lng eontiuinais ant«-riorly and e.xternally Avith the large anterior buttress 
so cliaracteristie «»f this s|H*eies. The internal cingulum of the true molars is only 
very slightly develo|M-d. 'Phe internal cones of the molars are large and rather 
sharp : t In-n- an- no signs 4>f (-onnectiiig ridges betiveen them and the external lobes 
of the luolars. 
I In- h\ |MK‘<ines 4»f nndars 1 and 2 are rather large and not placed tio far 
iN-liiinl and to the inside as in Pelmatotheritu}!. The jiresence of a small rudimeiit- 
nrv 4-ouule (h \ |MK-one?) n|Nni the last ujijier molar of this species is not uncomnion. 
W V hav4> such an (-.\aui]de in the Princeton collection on No. 10,276. The fine 
series ot up|M*r molars ol this sjH-eies in Professor Cope’s collection also show a small 
hy|NN-one u|Min the last molar. The di.scussion of this character and its relation to 
the t\viM-«>ne«l h»nu «»f molar occurring in Limnohyops will be considered under the 
In-a.l ..r I hat g4-nus. I may ineivly add here that Marsh’s L. laticeps is very closely 
n-lat4Ml in its .h-ntal characters to P. pahidosus. The two series of molars 
that hav«- Ikvii (le.scrilK-d under this species as belonging to the male and female 
n-s|H-«-ti\.-ly .iffer no other iK-culiar characters in the conformation of their lobes, 
hut III the condition of the enamel they present a striking difference, in the fact 
that 111 the sup|M).m-,l male the enamel is strongly Avrinkled, Avhereas in specimen 
No. HMHi't (HupiMised female) the surface of the enamel is perfectly smooth. This 
ra< t< r is an iin]M)itant one as Cope', in his simcific table of this family, 
'Torliary jiagt- aw. 
