NORTH AMKK10AN EARLY TERTIARY BRYOZOA. 



59 



p.ra x 



FIG. 12. Hydrostatic functions. 



A. Operculum of Dakaria (Schisoporella) gelida Waters, 1903. 



B. Interior of Da karia (ScJiixoporclla) gelida Waters, 1903. (After Waters.) 



C. Compensatrix of Phonicosia sanguinea Norman, 1808. (After Harmer, 1902.) 



D. Operculum of HippoponcUa hippopits Smitt, 1867. (After Waters, 1900.) 



E. Interior of HippoporeUa mitltilamellosa, new species, X 20. 



F. Compensatrix of Hippodiplosia pallasiana Moll, 1803. (After Harmer, 1902.) 



G. Operculum of Smittina tripora Waters, 1903, X 85. 



H. Apertura of Smittina tripora Waters, 1903, X 85, with operculum and below it the avicu- 



larian glands with the mandible above the glands. 



I. Compensatrix of Smittina trispinosa Johnston, 1837. (After Harmer, 1902.) 



J. Operculum of Microporella malusi Audouin, 1S2G. (After Waters. 1878.) 



K. Compensatrix and ascopore of MicroporeUa malusi Audouin. 1826. (After Harmer, 1902.) 



6, polypide bud; 66, brown body; cond, condyle; corn, cornieula ; c. s, Compensatrix; in. p, 



ascopore (=median pores) ; occl, occlusor muscles of operculum; op. gl, opercnlju- cchimls: p. c. 



dietellae (=pore chambers) ; p. m, parietal muscles: p. v. m, parietovaginal muscles; r, zooecia. 



