NO. 2 OSBURN; eastern pacific BRYOZOA CHEILOSTOMATA 311 



A slight correction should be made to the above description, as the 

 oral avicularium is asymmetrical in origin, arising from one areolar pore, 

 while in Porella the avicularium is median and is connected with areolar 

 pores on both sides. 



Ragionula rosacea (Busk), 1856 

 Plate 36, fig. 7 



Eschara rosacea Busk, 1856:33, 

 Escharoides rosacea, Hincks, 1880:336. 

 Discopora rosacea, Nordgaard, 1918:77. 



Zoarium erect from a small base, with a few flattened bilaminate 

 branches or lobes, more or less contorted ; white to light rose colored. 

 The zooecia are small, 0.40 to 0.50 mm long by 0.25 to 0.35 mm wide; 

 ovate or irregular in form; ventricose when young but soon becoming 

 indistinct as the granulated pleurocyst quickly becomes excessively thick. 

 There are a few areolar pores, but those of adjoining zooecia are fused 

 into single pores by the secondary calcification so that there appears to be 

 only one row which marks the lateral limits of the zooecia. The primary 

 aperture, showing only on the very youngest zooecia, is short-elliptical, 

 the proximal border nearly straight ; the operculum has the form of the 

 aperture and bears an elongate sclerite on each side a little within the 

 border; the secondary aperture bears a deep sinus which is usually dis- 

 torted by the oral avicularium at one side of the notch. The oral avicu- 

 larium is small, with a semicircular mandible ; small rounded avicularia, 

 often slightly elevated, are occasionally present on the frontal. 



The ovicell is hemispherical, smooth, and soon becomes completely 

 immersed in the thick crust. 



It is an arctic species, known from the Kara Sea to Greenland and 

 down the Atlantic coasts to Scotland and Labrador. 



Point Barrow, Alaska, Arctic Research Laboratory, G. E. MacGini- 

 tie, collector, common and well-developed, one colony measures 18 mm 

 high by 22 mm wide with 10 lobes. Its occurrence at Point Barrow 

 indicates that it is circumpolar in distribution. 



Genus DIATOSULA Canu and Bassler 1927 



"The ovicell is hyperstomial and opens in the peristomie; it bears a 

 triangular area bordered with pores. The frontal is very thick and 

 smooth. The aperture is formed of a large anter separated from the 

 small poster by two cardelles. The peristomice bears a pseudo-rimule 



