Ossification has just begun in the maxilla. The chondrifying scapula now possesses a cartilaginous coracoid process. There are signs of joint cavity in the shoulder. The tips of the first 7 ribs are connected by a narrow strip of condensed tissue and the 1st rib is fused with the median end of the clavicle perhaps indicating beginning of manubrium. Right and left sternal bars are present and fuse cranially to form the episternal cartilage by this stage.
Cartilage is found within the three mesenchymal primordia of the hip bones.
12 ribs on each side are present. The basi-occiput is cartilaginous by this stage. It is continuous with the exooccipitals, otic capsules and basisphenoid and it forms the anterior edge of the foramen magnum. The foramen magnum is not complete, however. The squamous occipital halves half not yet fused in the midline and the dorsal margin is a thin membrane of connective tissue.