[11] As noted above, the melodies of the minnesongs were from the beginning dependent on the metrical and poetical structure of the strophe. The three principal kinds are the song (_Lied_), the lay (_Lerch_), and the proverb (_Spruch_). [12] The word madrigal was used at various periods to apply to two other forms in addition to the one here described: (1) the solo madrigal or _madrigale concertate con il basso continuo_, and (2) the madrigal with accompaniment for several instruments, ‘apt for viols and voyces,’ as the old English song books have it. [13] Grove’s ‘Dictionary of Music and Musicians,’ Vol. IV, Art. ‘Sumer is icumen in.’ CHAPTER II THE POLYPHONIC PERIOD The Gallo-Belgic School; the Netherlanders; the Mass and its liturgical significance; the use of secular subjects--Conditions that fostered continuity of development: the ‘Mass of Tournay’; Dufay and Okeghem; Hobrecht’s _Parce Domine_; Josquin des Prés’ masses and motets; his expressive style--The motet as an extra-liturgical form; its development; its later characteristic style; distinction between sacred and secular music--Orlandus Lassus: his ‘Penitential Psalms’; his tendency toward a simpler style; his _Gustate et Videte_ and other compositions--Palestrina’s reforms, methods, and style; his masses, _Papæ Marcelli_, _Brevis_, and _Assumpta est Maria_; his motets and other compositions: Vittoria and others--Madrigal writers of the sixteenth century: Festa, Arcadelt, Willaert, Byrd, Morley, etc. I