NO. 1 OSBURN : EASTERN PACIFIC BRYOZOA CHEILOSTOMATA 75 



Genus PARELLISINA Osburn, 1940 



This genus was erected by Osburn (1940:360) to include those 

 species, formerly listed under Membranipora and Callopora, in which 

 the avicularium is always associated with a heterozooecium or kenozooeci- 

 um. The avicularian chamber is proximal to that of the kenozooecium 

 and separated from it by a vertical wall. Besides the genotype, Membrani- 

 pora curvirostris Hincks, the following species seem to belong here: 

 M. falcata MacGillivray, M. albida Hincks, Callopora tenuissima Canu 

 and Bassler, C. subalbida Canu and Bassler, P. latirostris Osburn and 

 Ellisina latirostris Silen (not Osburn). 



o^ Parellisina curvirostris (Hincks), 1862 

 Plate 8, fig. 8 



Membranipora curvirostris Hincks, 1862. 

 Ellisina curvirostris, Harmer, 1926:228. 

 Callopora curvirostris, Canu and Bassler, 1928 :32. 

 Ellisina curvirostris, Hastings, 1930:711. 

 Parellisina curvirostris, Osburn, 1940 :361. 



Zoarium encrusting. Zooecia separated by grooves, gymnocyst small 

 or wanting; mural rim thin, little raised; a vestigial spine on either side 

 of the aperture, often wanting, and occasionally others on the lateral 

 walls; a narrow granulated cryptocyst. Ovicell hyperstomial, small but 

 prominent, globose, the frontal surface delicately granulated. The avicu- 

 larium is interzooecial, large and more or less curved sideways ; followed 

 in series by a kenozooecium which varies considerably in size and form 

 and which is covered by a membrane ; its opesium is usually more or less 

 triangular and a delicate mural rim may be present. Hastings recorded 

 the species from the Galapagos Islands. Otherwise it is known around the 

 world in warmer seas. 



Hancock Stations: 142-34, Clipperton Island, west of Mexico, and 

 147-34, 155-34, 198-34 and 362-35, all from the Galapagos Islands. Also 

 in the Galtsoff collection on pearl oyster shells from the Gulf of Panama. 



Genus BIDENKAPIA new genus 



Zoarium encrusting and loosely attached or rising in flabellate ex- 

 pansions or contorted frills. Zooecia large, walls very high and thin with 

 multiporous rosette plates; dorsal wall smooth with numerous white 

 punctations ; gymnocyst and cryptocyst well developed ; no spines ; usu- 

 ally a single large avicularium covers the whole breadth of the gymno- 



