PAL.EOSYOPS LEIDY, AND- ITS ALLIES. 
277 
PAL,E08Y0PS. 
Syn. {Liiiiiioliijits — JIaxtili.) 
The dentition of Pala:osyops lias been partially described bj^ Leidy, althongh 
liis descriptions are faulty in not indicating distinctly the sjiecific difference betAveen 
the species. lie Aras either not familiar AAutb the genus Telmato thorium, or con- 
sidered it the same as Palceosyops, for in the material described liy him there 
are no teeth AAdiich can be referred to Telmalotherium. Leidy, in giA'ing the 
dental character of his tiim species of Palceosyops, seems often uncertain under AA^hich 
.species he should place ncAV material, and is constantly doubting their specific dis- 
tinction. He has given us a tolerably full account of the dentition of P. minor, 
but he compares the dentition of P. paludosus with that of the former species, and 
speaks of their A^ery close similarity in dentition ; liut ho does not point out fully 
the specific characters of each s^iecies. Tlie following generic characters are mainly 
derived from the typical species — auz : P. paludosus. 
Generic Characters : — Dentition : — The incisors in this genus form a closed 
series, their croAvns being short and triangular in outline. The posterior face of the 
incisors is not deeply excaA'ated as in Telmatolherium, and there is no prominent 
basal ridge as in the latter genus. The diastemas betAveen the canines and incisors 
may be large, but the posterior canine diastema is generallj^ Amry small. 
The canines are A’ery large, bear-like tusks, aud round in section. The croAAUAS 
of the upper premolars are loAver than those of Tehnatotherium, and their external 
lobes are less acute. The first premolar is much simpler than that of TelmatotJier- 
lum. The second has a aa'cII dcAmloped internal lobe. In the last tooth of this series 
the external lobes are generally separated by a median buttress, which is Avanting in 
Telmatotherium. In the less specialized mendjer of the genus the transAmrse diam- 
eter of pm. 4 and m. 1 is considerable. The intermediate conules of the premolars 
are generally Avantiug. In the inferior premolar series the first tooth is quite 
simple in structure, having no prominent licels. The second has no rudimentary 
internal cone as in some species of Lambdotlm'him, and its anterior cone is larger than 
the posterior. The fourth inferior premolar diflers from that of Telmatotherium in 
being simpler in structure. The superior true molars have low croAvns and their 
transverse axes exceed the antero-posterior. The external V’s in this genus are 
round and narroAV ; their anterior buttress is very prominent and the median buttress 
is not strongly constricted off. Prominent ribs may lie present in . some of the 
species of this genus on the external face of the superior molars. In contrast to 
Linmohyops oulj' the protoconules are developed on the true molars, the presence 
of a metaconnle being a A'ery rare occurrence in this genus. The internal cones of 
the molars are round, blunt, and the hypocone of m. 1 and m. 2 is more strongly de- 
A^eloped than in Telmatotherium. The last superior molar has only one internal 
cone, but traces of a hypocone may be present on this tooth. As a rule nearly 
-all the species in this genus have, the external cingulum Avanting. The inferior 
