1. The Decree of Gratian _(Decretum Gratiani)_ in three parts, published c. 1142. Part I contains one hundred and one distinctions (_distinctiones_) or divisions, which treat of matters relating to ecclesiastical persons and offices. Dist. XXXVII is translated below. Part II contains thirty-six cases (_causae_) each of which is divided into questions (_quaestiones_). These questions deal with problems which may arise in the administration of the canon law. Part III contains five distinctions which deal with the ritual and the sacraments of the church. Under each distinction, or question, are arranged the canons--the views of ecclesiastical authorities--on the matter under discussion. 2. The Decretals (_Decretales_), in five books, published by Pope Gregory IX in 1234. 3. The Sixth Book (_Liber Sextus_), a supplement to the Decretals by Pope Boniface VIII, 1298. 4. The Constitutions of Clementine (_Constitutiones Clementinae_), 1317. 5. Several collections of papal laws not included in those above, known by the general title of _Extravagantes_, i.e., laws _extra vagantes_, or outside of, the four compilations just mentioned. Among all these the _Decretum_ of Gratian was the great innovation which first marked out Canon Law as a distinct field of learning, separate from both Theology and Roman Law. It was written as a text-book; "it was one of those great text-books which take the world by storm." It created an entirely new class of students, separate from those devoted to Arts, Theology, Roman Law, and Medicine,--just as the development of Engineering and other new professional studies have created new groups of university students to-day,--and thereby increased the resort to the universities.