BRYOZOANS FROM CHATHAM ISLAND 
Figs 26-29 Disporella sp., IGNS BZ 205. 26, entire colony encrusting a stylasterid, x 14.27, edge of disk showing autozooidal and kenozooidal apertures, x 
134. 28, one autozooidal and two kenozooidal apertures, x 465. 29, floor of brood chamber, with part of roof (?0vergrown) present at upper left, x 29. 
REMARKS. The loss of the brood chamber roof and the relative 
paucity of zooidal characters precludes naming this single specimen. 
Class GYMNOLAEMATA Allman, 1856 
Order CTENOSTOMATA Busk, 1852 
Suborder EUCTENOSTOMATA Jebram, 1973 
Family IMMERGENTIIDAE Silén, 1946 
Genus IMMERGENTIA Silén, 1946 
TYPE SPECIES. Immergentia californica Silén, 1946; original 
designation; Recent, California. 
Figs 30, 31 
MATERIAL. IGNS BZ 206, a single colony fragment from Pukekio, 
Chatham Island. 
Immergentia sp. 
DESCRIPTION. Colony boring in molluscan shell, the positions of 
zooidal orifices indicated by perforations in the shell surface. Perfo- 
rations circular or, where the shell surface is slightly eroded, 
spindle-shaped, giving evidence of each zooid being connected 
directly to a principal stolon on each side of the ‘spindle’. Width of 
zooid at level of stolon connection 0.09 mm. Apparent distance 
between one zooid opening and the next connected by the same 
principal stolon 0.65 mm. Zooids vertical in the shell substratum, 
0.52-0.58 mm long measured from the depth of the excavation. 
Principal stolons connected by adventitious (secondary) stolons that 
arise quite close to the zooidal aperture or at varying distances 
between consecutive apertures. 
REMARKS. The monogeneric Immergentiidae is first recorded from 
the Santonian of Germany (Taylor 1993), subsequently becoming 
widely distributed in the Miocene of Europe, the USA, southeastern 
Australia, and New Zealand, and extending through the remainder 
