NO. 3 OSBURN : EASTERN PACIFIC BRYOZOA — CYCLOSTOMATA 647 



Diaperoecia claviformis new species ^ 



Plate 66, fig. 11 



Zoarium encrusting on a shell, consisting of a ligulate branch, 0.65 

 mm wide, which terminates in an asymmetrical rounded expansion 2 

 mm in width. The tubules are short, their outlines inconspicuous, 2 rows 

 on the basal portion; the peristomes moderately high and unusually 

 close together, not connate and not seriated, 0.16 to 0.18 mm in diameter, 

 the apertures 0.13 mm; the younger tubules have the walls perforated 

 with small pores but these become closed with age. 



The ovicell is a conspicuous, ventricose area covering most of the 

 expanded part of the lobe and enclosing 12 peristomes which are quin- 

 cuncial in arrangement; among these the narrow lobes of the ovicell 

 are evenly distributed around the peristomes. The ooeciostome is near 

 the proximal end, a cylindrical erect tube, connate with a peristome at 

 its base only, the orifice round and 0.10 mm in diameter. 



The species has some resemblance to D. johnstoni, especially in the 

 narrow ligulate branch and suddenly expanded lobe, but the measure- 

 ments are smaller, the peristomes much more closely associated, and the 

 meandering branches of the ovicell very narrow. 



Type, AHF no. 92. 



Type locality, Hancock Station 1624-48, off Santa Catalina Island, 

 southern California, 33°23'48"N, 118°21'05"W, at 36 fms, one colony 

 on a shell. 



Family TubuHpoHdae Johnston, 1838 



"Zoarium entirely adherent, or more or less free and erect, multiform, 

 often linear, or flabellate, or lobate, sometimes cylindrical. Zooecia 

 tubular, disposed in contiguous series, or in single lines. Ooecium an 

 inflation of the surface at certain points, or a modified cell." (Hincks, 

 1880:424). 



"Cyclostomata in which the zooecia are restricted to one surface of 

 the colony and are commonly arranged in connate alternating series. 

 Cancelli are absent in the majority of the species. The ovicell is a modi- 

 fied zooecium which is usually much dilated in the region where the 

 embryos undergo their development." (Harmer, 1915:119). 



This is a large and difficult family and its analysis is complicated by 

 the great number of fossil forms, often without ovicells, that have been 

 described. As a rule they are adherent to the substratum, more or less 

 lobate, with the zooecial tubes arranged in fascicles, and the ooecium 



