The rental for works not on the official list was somewhat higher, as these would not be called for so continuously and as the preparation of supplies of the same must, therefore, be more of a speculation. In renting manuscripts outside of Bologna (which could be done only under special permission of the university authorities and which occurred as a rule only with members of other universities) an additional two _denarii_ for a _quaterne_ could be demanded. Students renting the _peciæ_ were obliged to deposit a pledge of sufficient value to secure the _stationarii_ against loss. Between the regulations applying to the _stationarii peciarum_, and those controlling the general _stationarii_, who had authority to sell as well as to rent and whose business lay outside of the university, there were various differences. The general _stationarius_ appeared to have undertaken from time to time the sale of books on commission, which to the university _stationarius_ was forbidden. One of the earlier university regulations prohibited students from purchasing manuscripts with a view of selling them again for a profit, but this, according to Savigny, fell into disuse in the course of the fourteenth century. As late as 1334, the regulations of Bologna strictly prohibited students from taking with them, on leaving the universities, any books whatsoever, without a special authorisation on the part of the heads of their respective Faculties. Regulations of this kind naturally interfered with the normal development of the book trade in a city so largely dependent upon its university as was Bologna, and formed one cause for the greater activity of the general book trade in cities like Venice, where the regulations of the commune were not supplemented by those of university authorities. The city statutes of Bologna of 1259, prohibited the _stationarii librarii_ from taking a higher commission on the sale of manuscripts than two and a half per cent. It was also specified that no sale of a work left on commission should be made without the direct knowledge of the owner. The _stationarius peciarum_ belonged at the outset to the membership of the university, and, in accepting the authority of its supervision and its regulations, enjoyed also the university privileges, which included freedom from certain municipal obligations. Many of the university _stationarii_ belonged, as mentioned, to the class of _bidelli_.