A term used very rarely in the English language to refer to a digit (the three phalanges) together with its associated metacarpus or metatarsus. The German equivalent (Strahl) is encountered more frequently, particularly with regards to the evolution of Ungulates (mammals which have less than 5 digits or rays). Horses have only one 'ray' i.e. only one metacarpus/tarsus and one set of phalanges per limb.