As with footprints, (animatronic dinosaur)it is difficult to assign a fossil egg to a dinosaur species, and it can only he successfully accomplished in rare occurrences when an identifiable embryo can be found inside the egg, or if a nest has the skeleton of a parent nearby.
The south German Solnhofen skeleton of Compsognathus has a number of spherical objects associated with it.(dinosaur equipment) They are thought to be unlaid eggs that burst out of the body cavity after the animal died. Such an association of eggs and skeleton is very rare, though.
As with footprints, palaeontologists give names to particular fossil eggs – names that do not imply identification of the egg layer. Such a classification is an “oospecies”.
Most dinosaur eggs are found in nests. Occasionally they look as if they have been laid in holes in the ground without much preparation – a spiral of eggs found in France is thought to have been laid by a stegosaur rhat just deposited them and left. Most of the nests that we know about are quite complex structures, and are found together in rookeries or nesting sites.(Dinosaur Playground Equipment) The nests laid by the duckbill ornithopod Maiasaura in Montana are the best studied. A typical nest consists of a mound of mud or soil, with a depression in the top. That depression is filled with ferns and twigs, providing insulation for the eggs that are laid inside it. Each nest is positioned about an adult dinosaur length from the next, so that they do not disturb one another.