Overview of classic cadherin mRNA expression in the APH of developing chicken embryos at E14 and E18. (A, B) Thionin staining for anatomical structures. (C, D) Cdh2. (E, F) Cdh4. (G, H) Cdh6B. (I, J) Cdh7. (K, L) Cdh8. (M, N) Cdh9. (O, P) Cdh11. (Q, R) Cdh12. (S, T) Cdh18. (U, V) Cdh19. (W, X) Cdh20. APHm, the medial part of the APH; APHi, the intermedial part of the APH; APHl, the lateral part of the APH; APHcl, the caudolateral part of the APH. Dashed lines indicate the division between subregions. The asterisks indicate artefacts. Scale bar=1 mm.