Fig. 4. Skeletal preparations of wild-type and mutant neonates. (A-E) Wild-type neonates. (A'-E') Mutant littermates. Bone is stained with Alizarin Red and cartilage with Alcian Blue. (A,A') Lateral view of the skull showing microcephaly and the lack of the squama temporalis (st) in the mutant (A'). (B,B') Tracheal and laryngeal cartilages in the wild type (B) and mutant (B'); th, thyroid; cr, cricoid cartilages; hy, Hyoid bone. (C,C') Lateral view of the mandibles; note the lack of the coronoid (cor), condylar (con) and angular (an) processes in the mutant (C') jaw. (D,D') Dorsal view of the base of the skull. as, alisphenoid; pl, palatine; ps, presphenoid; bs, basisphenoid; bo, basioccipital; tr, tympanic ring; oc, otic capsule. (E,E') Ventral view of the cervical vertebral column. The anterior arch of the atlas (aaa) is missing in the mutant and the ossification centres of the vertebral bodies (vb) are reduced.