AETIODACTYLA. 
345 
Pliauchenia vulcanorum, Cope. 
Plate Ixvii, fig. 5. 
Loc. cit., p. 259; loc. cit., ii, p. 990. 
Represented by the left maxillary bone of a Camel of about the size 
of the existing- Dromedary, and considerably larger than the species last 
described. The dental formula is, molars 4-3. The first premolar is only 
removed from the second by a diastema equal to the long diameter of the 
latter. The latter has no inner cingulum, while in the third it is so strong as 
to constitute an internal crescent. The third is much larger, and exhibits the 
usual single external and single internal crescents. The first molar is stout, 
long-rooted, and furnished with a strong ridge on the outer side, bounding 
the posterior crescent-bearing column in front. There is a weak ridge on 
the middle of the anterior column, and only a rudiment on the last premo¬ 
lar. There are no cingula on either the inner or outer bases of the crown. 
The enamel is nearly smooth. A palato-maxillary foramen issues opposite 
the anterior border of the base of the third premolar. 
Measurements. 
M. 
Length from the posterior border of the first premolar to the posterior border 
of the first molar.... 0. 090 
Length of the first true molar. 0.030 
Width of the base of the crown of the first true molar...... 0.024 
Length of the fourth premolar..... 0. 019 
Width of the base of the crown of the fourth premolar. 0. 018 
Width of the palate at the first true molar... ... 0. 040 
The typical specimen was found near Pojuaque, a village of the Pueblo 
Indians. Various bones of Camels of the size of the P. vulcanorum were 
also found, some of which doubtless belong to it. 
h’ragments of Camels of the larger proportions of this species are 
abundant in the Santa marls. One of these is a left premaxillary bone 
without apex, and with adjacent portions of maxillary. The three included 
fangs of incisor, canine, and premolar, are robust. A fragment of mandible 
includes bases of three premolars of the size of those of the Procamelus 
occidentalism-sindi may belong to that species. A portion of the maxillary 
bone of a Camel of the same size supports the three milk-molars, and the 
first permanent molar half protruded. The latter has the dimensions of the 
