Peerage of England
The ranks of the English peerage are, in descending order, Duke, Marquess, Earl, Viscount, and Baron. While most newer English peerages descend only in the male line, many of the older ones (particularly older baronies) can descend through females. Under English inheritance law all daughters are co-heirs, so many older English peerage titles have fallen into abeyance between various female co-heirs.
List of viscountcies in the peerages of Britain and Ireland
The majority of viscountcies are held by peers with higher titles, such as duke, marquess or earl; this can come about for a number of reasons, including the title being created as a subsidiary title at the same time as the higher peerage, the holder being elevated at a later time to a higher peerage or through inheritance when one individual is the heir to two separate titles.