Dentary

They include the lack of dentary symphyseal splaying around the canines and the lack of an obliquely oriented lower tooth row. ❋ Darren Naish (2006)

Theretairus (Simpson 1926) is known from two specimens (the holotype is a single dentary from Como Bluff), although some consider it to be a juvenile form of Opisthias. ❋ ReBecca Foster (2008)

But in the Yixian Formation enantiornithean Protopteryx (image at left: taken from Dinosaur. net.cn) there are just two conical, unserrated teeth in the premaxillae and two subtriangular teeth at the dentary tips (Zhang & Zhou 2000). ❋ Darren Naish (2006)

The euenantiornithean Eoenantiornis has four subconical teeth in each premaxilla while there were probably six or seven teeth in each dentary, the rostral-most two of which were larger than the others (Zhou et al. 2005). ❋ Darren Naish (2006)

Pressure-sensitive organs termed Herbst corpuscles, embedded within pits on the premaxillary and dentary tips, are closely packed and particularly numerous in birds that probe sediments. ❋ Darren Naish (2006)

It seems that these birds lost the teeth from the back of the jaws first, and kept their premaxillary and dentary-tip teeth the longest. ❋ Darren Naish (2006)

Firstly, the medial surface of the dentary possesses trough-like concavities that Fox et al. interpreted as areas for the articulation of post-dentary bones. ❋ Darren Naish (2006)

While sorting the faunal material in Barbuda, I saw some bones that can identified from their unique characteristics, such as the dentary bone (part of the lower jaw) of the parrot, surgeon, and doctor fish. ❋ Unknown (2007)

In this animal, not only was the ancient reptilian joint between a reduced quadrate and articular still present, but also the new mammalian joint between the squamosal and dentary bones had come into functional being. ❋ Unknown (2006)

The therapsid-mammal transition was completed with the appearence of the morganucodonts in the late Triassic: The axes of the two jaw hinges, dentary-squamosal and articular-quadrate, coincide along a lateral-medial line, and therefore the double jaw articulation of the most advanced cynodonts is still present … The secondary dentary-squamosal jaw hinge had enlarged in the morganucodonts and took a greater proportion if not all of the stresses at the jaw articulation. ❋ Unknown (2006)

In later fossils from the same group, however, the quadrate-articular bones have become smaller, and the dentary and squamosal bones have become larger and moved closer together. ❋ Unknown (2006)

All mammals, living or fossil, have a single bone, the dentary, on each side of the lower jaw, and all mammals, living or fossil, have three auditory ossicles or ear bones, the malleus, incus and stapes. ❋ Unknown (2006)

In mammals, by contrast, the lower jaw is made up of a single bone, the dentary, which articulates with the squamosal bone in the skull to form the jaw joint. ❋ Unknown (2006)

Their fossil representatives have synapsid skulls, they have 3 ossicles and the jaw is formed from one bone the dentary. ❋ Unknown (2006)

It is true that these bones were very much reduced, so that the squamosal bone of the skull and the dentary bone of the lower jaw the two bones involved in the mammalian jaw articulation were on the point of touching each other. ❋ Unknown (2006)