A Skeleton may be created by use of a ZOMBIE spell on an intact skeleton. A Zombie which has been kept alive for so long that all its flesh has disappeared will eventually become a Skeleton. This usually takes several years.
 Skeletons are treated just like Zombies. However, they are immune to arrows, which tend to pass right through them without doing damage. Other weapons, and magic, affect them normally. Skeletons are also somewhat fragile. Any single hit of 8 points damage or more will totally shatter and destroy a skeleton, regardless of the ST it had remaining.
 Skeletons often carry shields. Occasionally they wear clothing or armor, but their masters usually find it more convenient to leave them in their naked bones, the better to horrify those they meet. - In the Labyrinth 1980 Page 59