The origin of the first palmar interosseous muscle is on the ulnar aspect of the base, and can sometimes extend onto the shaft . In contrast to the other metacarpals, the first metacarpal has no articular facets on the sides of its base ( for intermetacarpal articulations ) because it articulates exclusively with the trapezium.
32.
The "'interosseous crest or lateral border "'is thin and prominent, especially its central part, and gives attachment to the interosseous membrane; it commences above in front of the fibular articular facet, and bifurcates below, to form the boundaries of a triangular rough surface, for the attachment of the interosseous ligament connecting the tibia and fibula.
33.
According to Rauhut ( 2000 ), " Elaphrosaurus " can be distinguished based on the following characteristics : the cervical vertebrae possess thin latero-ventral laminae, bordering the posterior pleurocoel ventrally, the cervical vertebrae are strongly concave ventrally, with the ventral margin arching above the mid-height of the anterior articular facet at its highest point, the brevis shelf forms an almost horizontal lateral flange, the distal end of the ischium is strongly expanded into a triangular boot.
34.
In " Gigantornis " the articular facet for the furcula consists of a flat section at the very tip of the sternal keel and a similar one set immediately above it at an outward angle, and the spina externa is shaped like an dynamically soaring seabirds, and considering the 30 million years or so that separate " Gigantornis " and LHNB ( CCCP )-1, the Paleogene taxon may be very close to the Miocene bird's ancestor nonwithstanding their differences.
35.
The "'posterior surface "'presents, at its upper part, a prominent ridge, the popliteal line, which extends obliquely downward from the back part of the articular facet for the fibula to the medial border, at the junction of its upper and middle thirds; it marks the lower limit of the insertion of the Popliteus, serves for the attachment of the fascia covering this muscle, and gives origin to part of the Soleus, Flexor digitorum longus, and Tibialis posterior.
36.
The bottom end of the humerus is larger than the top end; it bears three articular facets, with one for the preaxial accessory element ( the smallest of the three ), one for the radius ( the tallest of the three ), and one for the ulna ( which forms an angle of 120?with the radial facet ) . " Sveltonectes ", " Nannopterygius ", " Platypterygius hauthali ", and " Platypterygius platydactylus " all only have two; " Maiaspondylus ", " Aegirosaurus ", " Brachypterygius ", and " Platypterygius americanus " also have three, but the second facet articulates with a different bone; " Cryopterygius " has two on the left humerus and three on the right; and " Platypterygius australis " and " Platypterygius hercynicus " have up to four facets.
