270 
A .MK.MOIK ri’ON THE (iENUS 
of /‘.i/ifosyops, .)ur P. minor, in m.ccTtaiii, very little being known of the skull 
or ..r tl.e linil> l.<.neH. 'I'lie eliaraeters of the molars (see his PI. IV, figs. 8-G) 
arerlo.-*-lv similar to tliose of Telmatolherium ; they have the square form observed in 
that j'eiiiis. 
We an- imiehteil to Professor Marsh f()r having deserihed Litnnohyops laticeps, 
althongii at the tiim- of its <lescnption he created great confusion in the nomencla- 
tim- l«v totally igmn-ing la-idy’s |irevions description oi' Pai^eosyops. It was one of inj 
first diith-s in taking up tliis investigation to unravel the work done by Marsh, and 
att 4 -nipt t4i phn-e it in its true relation to that done by Leidy. Marsh at the time of 
«les<-rihing liis genus Telmatolherium did not appreciate its true relationship in Dipla- 
(odon and lat«-r in his " Inti-fslnction and Succession of Vertebrate Life,” jdaces the 
genus Paheosyops ia-.\t t<t that of Diplacodou in its evolution. This is an error. As 
I shall show in tia-ating of Telmatotherium. this genus was probably the direct 
fon-nnnn-r in tin- Hriilg«*r of the I'inta genus Diplacodori and I Ix-lieve Telmatolher- 
tum to lie tin- tninsition fiirin la-tween Palceosyops and Diplacodou. Also the state- 
nn-nt made by Marsh that I.imuohyops{=Limnohyus) is found lower in its geologi- 
«-al horixon than Pal(rosyop.<! incorrect. They both occur in the JJridger proper, 
ainl tin-n- is no iveonl n[' I Jmuohyops from the Wind River. 
Pnifi-s.siir ('o|M-’s collection of Pahv-osyops material is a small one; but owing to 
its iinii|iie cbaracler he has la-en enabled to describe a number of very interesting 
in-w s|M-<-ies. wbicli I find on «-omparison with other tin’ins to Ik- quite distinct. We 
an- hnlebt«-d t«i ('o|k- fbr having descrik-d the earliest known species from the Wind 
River l-sK-i-in- of Wyoming, namely, P. borealis-, and from this fbrmation he also de- 
s«-rilH-d the g4-nns Lambdolherium which he con.siders as the direct ance.stor of the 
Palasis\ops-I)qda<-<Mlon line. We consider that Lambdolherium may have been the 
aneoslor of Pahrosyops. but certain characters of its dentition— fbr exam])le, the loss 
of inf.pin. I— iHiints to its k-ing a side line, and not leading directly to Palceosyops. 
Pn.f.-ssiir ( ’o|H-’s <-olh-«-tion tains only one skull referal)le to the genus Limnohyops, 
naniely. Ins /,. fonHualis, and in 'relmatotherium material his collection is very 
liinit.-d A\e shall not detain the reader with a long de.scription of the original 
inat.-nal iqH.n which k-i.iy based his de.scriiitioms, but merelv add that the type 
siHvnm-n of P. paludosus is now in the Smithsonian Institution at AVashington. 
His Iat4-r niat4-rial of PaUrosyops, which was fully described in his report for 1873, 
.s now n, tin- Aca.Iemy of Natural S-iences of Philadelphia. Profes.sor Marsh’s 
* II • . <^tyeps .IS well as his L. robuslus and Telmatolherium validus 
‘ , Have,,. I ,v„K v..n- R,rl„nat, i„ teing 
' . V ", ,V|H. tlu,..k. t„' l,i. Tl.e 
inul'l ”tl"' *1 a kVl-*- -veix' ilescribud is all in his private col- 
■11- .•.Iiu";i,, : , 7""" Archa.„logy a, Princetoa College. 
osvophur. ' known material referable to the Pales- 
