This study investigates the variation between the accusativus cum infinitivo (a.c.i.) and quod clauses with verba sentiendi and declarandi in the Revelaciones, Books I-VII, of St. Bridget of Sweden (1303-73). This variation is considered to be a characteristic feature of late and mediaeval Latin. The author analyses grammatical patterns which are important or decisive for the choice of construction after the main verb in the text of the Revelaciones. These patterns are connected with semantic criteria such as assertivity, with the category of co-reference and with stylistic factors and must be regarded as fundamental to the Latinity of the Revelaciones. An examination of the moods in quod clauses, the sequence of moods and tenses and a brief survey of subordinate constructions with verba voluntatis and curandi is also included.