78 
BULLETIN 106, UNITED STATES NATIONAL MUSEUM. 
Membranipora villosa Hincks, 1880. 
Membranipora ( Flustra ) isabelleana D’Orbigny, 1839. 
M embranipora pura Hincks, 1880. 
Membranipora ( Flustra ) tehuelcha D’Orbigny, 1839. 
Membranipora nitens Hincks, 3 880. 
Membranipora hyadesi Jullien, 1888. 
Genus HETEROOECIUM Hincks, 1892. 
1892. Heterooecium Hincks, Contributions towards a General History of the Marine Polyzoa, 
Appendix, Annals and Magazine Natural History, ser. 6, vol. 9, p. 312. 
The ovicell is acanthostegous. 
Genotype. — Heterooecium ampleetens Hincks, 1881. Eecent. 
A, B. Membranipora membranacea Linnaeus, 1758. A. Ordinary zooecia, X 15. B. Abnormal 
cells (“tower zooecia”), X 15. (After Hincks, 1880.) 
C. Cyphonautes occidentalis Robertson, 1908, the larval stage of Membranipora villosa 
Hincks, 1880, X 70, showing the organism in optical section as it appears while still living and 
lying on its side, a, apex ; ab, aboral ; add. mus., adductor muscle ; ant, anterior ; ap. t, apical 
tuft; d, denticle; fi, fiber; int, intestinal tract; m, mouth; O, oral; post, posterior; pyr, pyriform 
body; rb, rib; re. d, retractile disk; st. c, stiff cilia; stm, stomach; sue, sucker. 
1852. Pyripora D'Orbigny, Paleontologie francaise, Terrain Cretace, Bryozoaires, vol. 5, 
Colony fixed, creeping over the surface of other bodies, formed of little regular, 
longitudinal and lateral lines of cells placed one after the other, not contiguous 
laterally, and disposed in a manner to represent creeping branches more or less 
extended. Cellules pyriform, narrow behind, and enlarged in front, open in dead 
or fossil individuals over the greater part of their anterior portion. No special 
pores, no accessory cells, nor ovarian vesicles. (After D’Orbigny, 1852.) The 
operculum is calcified. (Levinsen, 1909.) 
ab 
C *70 
Fig. 19. — Genus Membranipora Blainville, 1834. 
Genus PYRIPORA D’Orbigny, 1852. 
p. 538. 
