Pennaceous feathers are also known as contour feathers, and are present in most modern birds and in some species of maniraptoran dinosaurs. Pennaceous feathers have a central shaft (or rachis) with vanes branching off to either side. These vanes are also called Barbs, that are connected to one another with Barbules, tiny strands that criss-cross to form a kind of mesh that holds all the barbs together and with each other. Remiges and rectrices are specialized types of pennaceous feathers.