 The m1 is long and narrow . The anteroconid , the cusp at the front of the tooth , is oriented perpendicularly to the main axis of the tooth and on the lingual ( inner ) side is separated from the metaconid cusp . The protoconid , another cusp on the labial ( outer ) side , is connected at its back to a longitudinal crest , which in turn anchors the transverse mesolophid crest , and then joins the hypoconid labial cusp . In front of the hypoconid , an ectostylid ( a smaller cuspule ) is present . The entoconid cusp , located lingually , is relatively high and is separated from the mesolophid before it by a deep valley . Another crest , the posterolophid , is present behind the hypoconid . At the front of the m2 , crests known as the anterolophid and anterolabial cingulum are present before the protoconid and the metaconid . As on the m1 , a transverse mesolophid and an ectostylid are present . The hypoconid and the entoconid are present , as is the posterolophid behind them . Within the posterolophid , there is a small valley that is absent in N. rufus . Both m1 and m2 have two roots ; m3 is unknown . 
