---+---------------+-------------+
|Pleurapophyses.|Scapular. |Stylohyal. |Tympanic. |Palatal. |
+---------------+---------------+----------------+---------------+-------------+
|Haemapophyses. |Coracoid. |Ceratohyal. |Articular. |Maxillary. |
+---------------+---------------+----------------+---------------+-------------+
|Haemal Spines. |Episternum. |Basihyal. |Dentary. |Premaxillary.|
+---------------+---------------+----------------+---------------+-------------+
| Diverging |Fore-limb or |Branchiostegals.|Operculum. |Pterygoid and|
| Appendage. | Fin. | | | Zygoma. |
+---------------+---------------+----------------+---------------+-------------+

Owen's reasons for considering the pectoral girdle and the fore-limb
part of the occipital vertebra are as follows. In fish the pectoral
girdle is slung to the skull by means of the post-temporal bone
(supra-scapula, according to Owen) which abuts on the occipital arch. In
_Lepidosiren_, whose skeleton resembles the archetype in many ways, the
pectoral girdle is likewise attached to the occipital segment.

In most other Vertebrates the pectoral girdle has shifted backwards
along the vertebral column, by a "metastasis" (Geoffroy) similar to that
by which the pelvic fins in many fish have shifted up close to the
pectoral girdle. The scapula (with supra-scapula) is the pleurapophysis,
the coracoid the haemapophysis, of the occipital vertebra. The clavicle
is homologised with the slender bone in fish now known as the
post-clavicle, which shows a connection with the first or atlas vertebra
of the vertebral column, forming, according to Owen, the haemapophysis of
the atlas. Owen considers it no objection to this view that in other
Vertebrates the clavicle is anterior to the coracoid--"its anterior
position to the coracoid in the air-breathing Vertebrata is no valid
argument against the determination, since in these we have shown that
the true scapular arch is displaced backwards" (_On the Nature of
Limbs_, p. 63, London, 1849). In the pelvic girdle the ilium corresponds
to the scapula, the ischium to the coracoid, the pubis to the clavicle.
Hence the ilium is a pleurapophysis, the ischium and pubis are both
haemapophyses. The fore-limb is the developed "appendage" of the
occipital vertebra, the hind-limb the developed "appendage" of the
pelvic vertebra. They are serially hom