NO. 1 OSB URN : EASTERN PACIFIC BRYOZOA CHEILOSTOMATA 127 



Amastigia rudis (Busk), 1852 

 Plate 16, figs. 3, 4 and 5 



Caber ea rudis Busk, 1852 :377. 



Amastigia rudis, Harmer, 1923:322; 1926:349. 



Amastigia rudis, Silen, 1941 :80. 



Zoarium bushy, flabellate, coarse, 2 series of zooecia at the base to 8 

 in the terminal branches ; joints wanting. 



Zooecia moderate, 0.40 to 0.50 mm in length, closely set ; opesia ovoid, 

 narrowed distally; cryptocyst broad. Scutum more or less rounded, at- 

 tached distal to the middle of opesia. Spines, 3 outer and 1 or 2 inner, 

 all small. 



Frontal avicularia varying in size, those on the inner rows usually 

 small, with an acute triangular mandible oriented distally; on the outer 

 rows there are similar small avicularia, but these are often replaced by 

 giant avicularia which are oriented proximally ; marginal avicularia want- 

 ing. The dorsal avicularia are vibraculoid in form, oriented toward the 

 median line and proximally, the rostrum very narrow and extending 

 nearly to the midline of the branch, the mandible long and setiform. 



The ooecia are a little longer than broad, smooth and glossy, the 

 ectooecium covers only the distal end and extends around the sides leav- 

 ing a large area of the endooecium exposed. 



This species is apparently common and widely distributed in the 

 Western Pacific from Australia to Japan, but has not been reported from 

 the Eastern Pacific region. 



Hancock Stations: 1250-41, 1 mile south of San Benito Islands, Mexi- 

 co, 44 to 49 fms; 1245-41, 4 miles north of Todos Santos Island, Mexi- 

 co, 41 fms; 1187-40, off Bird Rock, Santa Catalina Island, 31 to 40 fms; 

 874-38 northeast of Anacapa Island, 45 fms; 1269-41, 1 mile west north- 

 west of Anacapa Island, 41 to 43 fms; 1281-41, 3 miles east of South 

 Point, Santa Rosa Island, California, 23 to 26 fms; 116-33, Cocos Bay, 

 Costa Rica, 2 fms. 



Amastigia biseriata new species 

 Plate 15, figs. 1, 2 and 3 

 Zoarium erect, white, flexible, entirely without joints, dichotomously 

 branched and the branches little divergent; biserial throughout the colony 

 except for the axial zooecium, which is excluded from the dorsal surface, 

 only its axial vibraculum appearing on the dorsal side ; attached by radi- 

 cles which run down the outer margins of the branches; the branches 

 triangular in cross section, the dorsal side flat; the single colony 30 mm 

 high. 



