Parliament of Australia
From 1901 to 1949, the House consisted of either 74 or 75 members (the Senate had 36). Between 1949 and 1984, it had between 121 and 127 members (the Senate had 60 until 1975, when it increased to 64). In 1977, the High Court ordered that the size of the House be reduced from 127 to 124 members to comply with the nexus provision. In 1984, both the Senate and the House were enlarged; since then the House has had between 148 and 150 members (the Senate has 76).
Leader of the Government in the Senate (Australia)
The position of Leader of the Government in the Senate does not have a constitutional basis, but has existed since the first parliament in 1901 through longstanding parliamentary convention. Although it has similarities to the Senate Majority Leader in the United States and the Leader of the House of Lords in the United Kingdom, it was not based on either of those, but rather on the position of Leader of the Government in the Legislative Council found in Australia's colonial parliaments. Because government is formed in the House rather than the Senate, there is no guarantee that the Leader of the Government will be drawn from the largest party in the Senate. Unlike the Prime Minister, there is no requirement for the Leader of the Government to command the confidence of the chamber. It is not a cabinet post in its own right, and the holder of the office has always held at least one ministerial portfolio (though sometimes only the mostly honorific Vice-Presidency of the Executive Council).