Manners of terminology and description in Galen's anatomy in the ancient Rome and their historical consequences up to the modern time.

The oldest extant anatomy textbooks compiled in ancient Rome were by Galen who described in writing most of the various parts and organs of the body. History tells us that ever since the time of Galen, anatomical terminology would be a necessary and beneficial feature, but it also brought unexpected and annoying consequences into the field. The benefits are readily apparent in the case of muscle terminology. Galen identified more than 150 different kinds of skeletal muscles, most of which were unnamed, hence difficult to identify without professional knowledge of anatomy. Vesalius introduced detailed anatomical illustrations in Fabrica (1543), which made the identification of the muscles easier. Bauhin then introduced proper descriptive names for the muscles in Theatrum anatomicum (1605), which enabled the identification of the muscles without illustrations. After the terminology became complex and diverse, a logically consistent standard nomenclature was established by Nomina anatomica (1895). The unexpected consequences may be found in the terminology of bones and joints. Galen gave 39 proper names for individual bones, and classified and termed the types of bony joints. Many of these terms have survived in modern anatomy as literal translations of the bone terms, as well as the joint terms. The annoying consequences may be found in the terminology of intestines. Galen divided the small and large intestines into three portions, such that the major part of the small intestine suspended by the mesentery was divided into two without sufficient reason. The Latin translations of jejunum and ileum were, respectively assigned to them by Mondino in his Anatomia written in 1316.