NO. 1 OSBURN: EASTERN PACIFIC BRYOZOA CHEILOSTOMATA 133 



Scrupocellaria bertholetti (Audouin), 1826 

 Plate 15, figs. 7 and 8, and 21, fig. 8 



Scrupocellaria bertholetti, Hastings, 1930:733. 

 Scrupocellaria bertholetti, Osburn, 1940 :386. 



Zoarium erect, branching, of moderate size. Zooecia somewhat elon- 

 gate (0.40 to 0.45 mm long by 0.15 to 0.18 mm in width), a little nar- 

 rowed proximal to the opesia which occupies somewhat more than half 

 of the front. The spines vary greatly in number and length ; usually there 

 are three outer (occasionally 4 or only 2), and 1 or 2 inner, outermost 

 and inner spines rarely briefly furcate. Usually there is a small inner 

 spine a short distance above the attachment of the scutum. The scutum 

 also varies from a single spine curving over the opesia to a triple-forked 

 structure with 6 or more sharp points. Frontal avicularia are always 

 present, either small ones with the mandible directed laterally, or giant 

 avicularia which are elevated and directed either proximally or laterally 

 and with strongly hooked rostrum. Occasionally these may appear lower 

 on the internode. The lateral avicularia are small, with a triangular 

 mandible, but here also giant avicularia may occasionally occur, having 

 much the same structure and size as those on the front and with a strong- 

 ly hooked rostrum. The vibracular chambers are small and short, some- 

 what triangular, with a transverse groove; the seta is small and usually 

 less in length than a zooecium ; the radicle chamber is rounded and situ- 

 ated at the proximal end of the vibracular chamber on the outer side. 



The species is widely distributed in the Red and Mediterranean Seas, 

 the eastern and western Atlantic and elsewhere. Hastings (1930) listed 

 it for the Galapagos Islands. 



The ooecia are subglobose, prominent, averaging 0.20 mm in width, 

 with scattered tubular pores. 



Hancock Stations: A common species dredged at 24 stations from 

 southern California to the Galapagos Islands ; intermediate localities, San 

 Benito, Isabel and Clarion Islands off the west coast of Mexico, the Gulf 

 of California as far north as Angel de la Guardia Island, Costa Rica, 

 and Panama. Low tide to about 100 fms. It is common in shallow water 

 and on the piles of docks about the harbors of southern California. 



