Due to an overwhelming approach in most of the young scientists to remain confined with laboratory based studies, many of the field-based disciplines, including Vertebrate Palaeontology are gone into the back benches. It is well aware of the fact that the Indian Subcontinent, particularly Siwaliks or sub-Himalayan ranges are known as the paradise of Tertiary vertebrate fauna, hence are the stronghold of Vertebrate Palaeontology. Studies on the Tertiary ruminants had already been very limited, as no book on the Siwaliks of the Northern Pakistan has yet been published todate. This book, therefore, is designed to serve as a text for students who are taking a first course in the Siwalik Palaeontology, and because many major in Zoology lack preparatory training in Vertebrate Palaeontology, no such previous Siwalik palaeontological study is assumed in Pakistan. The book is intended to supplement instruction in the classroom and laboratory by providing a fairly complete description of the late Miocene Siwalik ruminants. It is planed as a reference work, as I felt that there was a need for an up-to-date account of what is known about the Middle Siwalik ruminants.