The actual embryonic skeleton of the prosauropod dinosaur Massospondylus as preserved inside the egg. Note that the head and strongly bent neck are lying outside of the egg. It is not possible to determine if this is the result of an unsuccessful hatching or if the head and neck were pushed out postmortally. Estimated length of embryo is 6 inches (15 cm). The egg is about 2.4 inches (6 cm) long. Credit: Robert Reisz/University of Toronto at Mississauga