zygapophyses

As regards the vertebral column, if we examine this structure in any of the existing hoofed animals, we find that the bony processes called zygapophyses, which belong to each of the constituent vertebræ, are so arranged that the anterior pair belonging to each vertebra interlocks with the posterior pair belonging to the next vertebra.

Darwin, and After Darwin (Vol. 1 and 3, of 3) An Exposition of the Darwinian Theory and a Discussion of Post-Darwinian Questions George John Romanes 1871

The normals to the polished facets of these point, in the case of the anterior zygapophyses, up and in (mnemonic: ant-up-in), and in the case of the posterior, down and out.

Text Book of Biology, Part 1: Vertebrata 1906

All the vertebrae join with their adjacent fellows through the intermediation of certain intervertebral pads, and also articulate by small processes at either end at the upper side of the arch, the zygapophyses.

Text Book of Biology, Part 1: Vertebrata 1906

In all the hoofed mammals of this period the zygapophyses are flat.

Darwin, and After Darwin (Vol. 1 and 3, of 3) An Exposition of the Darwinian Theory and a Discussion of Post-Darwinian Questions George John Romanes 1871

In the lumbus, anterodorsally inclined spinous processes, non-revolute zygapophyses, and the anteroventral orientation of transverse processes indicate the potential for dorsoventral flexion of the trunk and vertebral column in general.

PLoS ONE Alerts: New Articles 2009

In C3-C7 the orientation of zygapophyses, the saddle-shape of vertebral body surfaces, and the imbrication of transverse processes suggest that the neck was more capable of dorsiflexion than lateral rotation.

PLoS ONE Alerts: New Articles 2009

Measuring a giant sauropod vertebra isn’t as simple as you might think: firstly, because the long articular processes (the zygapophyses) may be incomplete, secondly, because the zygapophyses might have become bent or distorted during preservation, and, thirdly, because there’s more than one way to gain a vertebra’s ‘total length’!

Archive 2006-07-01 Darren Naish 2006

Measuring a giant sauropod vertebra isn’t as simple as you might think: firstly, because the long articular processes (the zygapophyses) may be incomplete, secondly, because the zygapophyses might have become bent or distorted during preservation, and, thirdly, because there’s more than one way to gain a vertebra’s ‘total length’!

‘Angloposeidon’, the unreported story, part II Darren Naish 2006