protocone การใช้

• M 1 and M 2 have large protocone lobs.
• In addition, they have a prominent protocone on their first, upper molars.
• There is a protoflexus an indentation in the crown in front of the protocone.
• The upper molars have four cusps : paracone, metacone, protocone, and hypocone.
• There is a spur at the back of the protocone, suggesting a rudimentary hypocone.
• The two cusps on the middle part of the molar, the paracone and the protocone, are broadly connected.
• The main cusp is protocone; among the other two cusps, the paracone is higher but the metacone larger.
• The protocone is connected to the paracone by a protoloph, which lacks a small cusp ( the paraconule ).
• No crest connects the protocone to the metacone, but there is a cingulum at the back margin of the tooth.
• In the cheek teeth of " Pakicetus ", the protocone lobe increases from the first molar to the third.
• In " Nalacetus ", in contrast, the protocone lobe is larger in the first molar than in the second.
• The connection between the protocone and the paracone, the major cusps immediately after the anterocone, is located relatively far toward the front.
• It has a dominant central protocone flanked by denticles that decrease in size mesially and distally, resulting in a tooth with a triangular profile.
• The fossil genus " Nycticeboides " lacks the rounded lingual face of the protocone seen in ? " N . linglom " and possesses additional cuspules.
• They proposed that wear in the australosphenidan talonid occurs mainly on the rims, not in the talonid basin itself, and that australosphenidans may not have had a functional protocone.
• The parastyle is also less developed than in " Eosimias ", but the protocone, the main cusp on the lingual side of the tooth, is more expansive.
• As in M1, the paracone is connected to the front or middle of the protocone, the mesoloph is well-developed, and the valleys meet at the midline of the tooth.
• The mesoloph is present on M3, but the posteroloph, a crest at the back of the tooth, is absent or vestigial, as is the hypoflexus ( the valley between the protocone and the cusp behind it, the hypocone ).
• Flynn and colleagues identified two wear facets at the front and back margins of the talonid basin; they argue that these wear facets suggest the presence of a protocone ( another cusp on the outer side of the tooth ) on the upper molars.
• On M2, there is no protoflexus ( an indentation in front of the protocone, which on this tooth is the frontmost cusp ) and the valley between the paracone and the mesoloph, the mesoflexus, is not divided into two pieces by a paracone mesoloph connection.