139 p. : ill., map ; 26 cm.Includes bibliographical references (p. 129-137).One hundred six species of Bryozoa collected from the northern Adriatic in the vicinity of Rovinj, Croatia, are distributed among the orders Ctenostomata (8 species), Cheilostomata (79 species), and Cyclostomata (19 species). Ctenostomes are underrepresented in the collections relative to the two orders with calcified colonies. Five of the cheilostome species are new: Hagiosynodos hadros n. sp., Schizomavella subsolana n. sp., Cellepora adriatica n. sp., Celleporina siphuncula n. sp., and Rhynchozoon revelatus n. sp. (previously referred to as Rhynchozoon sp. II Hayward). Seven species named by Heller (1867) are stabilized by selection of lectotypes (Beania hirtissima, Adeonella pallasii, Hagiosynodos kirchenpaueri, Exidmonea triforis, Crisia recurva) and neotypes (Mollia circumcincta, Schizomavella cornuta) from Heller's collection in the University of Innsbruck Institute of Zoology. Lectotypes are designated for the Adriatic species Hippoporina lineolifera (Hincks, 1886) and for Schizomavella mamillata (Hincks, 1880). Beania cylindrica (Hincks, 1886) and Schizoporella asymetrica (Calvet, 1927) are recognized as species rather than as subspecific units. The species-rich cheilostome genus Schizoporella Hincks, 1877, which contains some of the most widely known fouling bryozoans, is designated a nomen protectum. The species name Smittina cheilostoma (Manzoni, 1869) is preserved as established usage