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shifted far back, the cranium short, brain cavity absurdly 

 small, the sagittal crest high and thin and the zygo- 

 matic arches enormously developed. Other odd fea- 

 tures are the pendant compressed plates given off from 

 the ventral surface of the jugals and two pairs of knob- 

 like processes on the ventral borders of the lower jaw. In 

 young individuals the knob-like processes are only rough 

 elevations, in some adults, especially the smaller species, they 

 are little more than rounded knobs, but in the larger forms 

 they become greatly elongated and club-shaped. Their use 

 seems to be wholly unknown. The dentition above and be- 

 low on each side is as follows : Incisors, three ; canines, one ; 



Figure 59 — Anterior portions of the upper and lower jaws of the 

 ancestral peccary. Desmathyus (Thinohyus) Siouxensis, Peter- 

 son, 1905. 



pre-molars, four; molars, three; total, fourty-four. The 

 canines both above and below are large and powerful. They 

 do not appear to be of any sexual significance as the females 

 developed them as fully as the males. Their use seems to 

 have been that of digging up roots, in view of the fact that 

 certain well preserved specimens show deep grooves on the 

 posterior side of the lower teeth near the gums, grooves that 

 could not have been caused by the attrition of the other 

 teeth. The neck is short and massive and well arranged for 

 the attachment of strong muscles necessitated by the great 

 length and weight of the head. The limbs are long, par- 



