I immediately opened the, "The call of the hen; or the science of selecting & breeding poultry for egg production" on PDF format, and what a nice book it is! First, I will search and find out if it is in print; if not, will make a copy of it. The details of anatomy is great! Thank you! Thank you!This old book has some tips on bird anatomy and photos that might prove useful. It's mainly an old book explaining how to select for breeding egg layers but goes into some detail into anatomy that you might like, and there are pictures of parts of the skeleton but anyway, give it a look: http://archive.org/details/callofhenorscien02hoga
The link is to a free online book but you can download it in many formats.