NO. 3 OSBURN : EASTERN PACIFIC BRYOZOA CYCLOSTOMATA 731 



side help to anchor the colony in place. These kenozooecial filaments 

 are most easily found near the periphery of the zoaria. The zoaria in 

 the collection measured between 2.6 and 3.0 cm in diameter. The zooecia 

 are small, hexagonal, usually bearing the apertures raised on papillae 

 which occupy nearly all of the ventral surface. The tentacle number is 

 16, determined from sections. 



Described by Smitt from Scandinavian waters, and recorded by Os- 

 burn from Captain R. A. Bartlett's dredgings in Wakeham Bay, Un- 

 gava, Canada. 



Hancock collection specimens are from Point Barrow, Alaska, Arctic 

 Research Laboratory, 13 fms, collected by G. E. MacGinitie. The 

 species evidently has a circumpolar distribution. 



Alcyonidium enteromorpha Soule, 1951 

 Plate 77, figs. 7 and 8 



Alcyonidium enteromorpha Soule, 1951:367. 



The zoaria are elongate without lateral branching, bearing a super- 

 ficial resemblance to the intestinal tract of a small mammal. Of several 

 zoaria in the collection the longest measured 61 cm in length and from 

 4 to 6 mm in width. Coiled in several loose folds the zoaria are attached 

 to the substrate without a differentiated "peduncle." The cuticle is 

 firm, mottled light brown to tan in color, and only moderately thick. 

 The zoaria are cylindrical and filled with a loose reticular connective 

 tissue. Within this meshwork of connective tissue may be found numer- 

 ous brown bodies, the product of degenerated zoids that have entered 

 the central cavity when the thin dorsal zooecial walls were ruptured. 

 From the ventral surface the zooecia are well defined, most easily found 

 in the portions of the zoaria where the cuticle is thin. On the greater 

 part of the zoaria, the lateral zooecial walls can be only faintly discerned, 

 and while not totally obscured, they are rather difficult to trace. The 

 ventral zooecial walls are smooth, with no oral papillae present. As 

 noted before, the dorsal zooecial walls are thin, almost to the point of 

 transparency. In shape the zooecia are varied, ranging from rectangular 

 to irregularly hexagonal, those containing mature polypides measuring 

 between 0.23 and 0.40 mm in length, and from 0.11 to 0.25 mm in 

 width. The tentacle number obtained from serial sections is 17. It 

 differs from A. pedunculatum Robertson, by virtue of its cylindrical 

 form, its extreme zoarial length, and its complete lack of a "peduncle." 



All of the specimens in the Hancock collection are from Alaska, off 

 Point Barrow, Arctic Research Laboratory, collector G. E. MacGinitie. 

 Collected at depths ranging from 80 to 123 fathoms. 



