NO. 3 OSBURN : EASTERN PACIFIC BRYOZOA — CYCLOSTOMATA 765 



3. Stalk short, basal bulb as long as or longer than the following 



internode, calyx large robusta 



Stalk usually much longer than the basal bulb 4 



4. Small species, seldom 2 mm in height, the internode little or 



not at all "perforated," joints simple, rare gracilis 



Taller species, 2 to 4 mm high, internode very thickly "per- 

 forated," joints simple, rare discreta 



5. Zoarium very large, reaching a height of 5 centimeters, pro- 



fusely branched ; muscular bulbs of varying size, sometimes 



gigantic; high Arctic gorbunovi 



Branches few, arising from enlarged stem nodes, basal bulbs 



of one size 6 



6. Tall slender species, long internodes, nodes moderately swollen ; 



branching occasionally at the nodes, the basal bulb short 



and ovate geniculata 



Stouter species, internodes shorter, the nodes much enlarged, 

 nearly every stalk bears one or more branches; the inter- 

 nodes with a few "perforations" ramosa 



Barentsia gracilis (M. Sars), 1835 

 Plate 82, fig. 3 



Pedicellina gracilis M. Sars, 1835:6. 

 Pedicellina gracilis, Hincks, 1884:208. 

 A scopodaria gracilis, Robertson, 1900:345. 

 Gonypodaria nodosa, O'Donoghue, 1923:5. 

 Barentsia gracilis nodosa, O'Donoghue, 1926:7. 

 Barentsia gracilis, Marcus, 1938:8. 



A small, delicate species, usually less than 1.0 mm in height. The 

 stolon is creeping, usually among hydroids and other bryozoans. The 

 basal bulb is of moderate size; the stalk short and lightly chitinized 

 with few or no "perforations." The largest calyx in our specimens 

 measures 0.25 mm high by 0.18 mm wide; the pedicel 0.95 mm high; 

 the basal bulb 0.35 mm high by 0.12 mm in diameter. The pedicel 

 usually bears no "perforations" but a few may be present. The joints, 

 which mark the variety nodosa Lomas, 1886, are rare in our material, 

 and they are only slightly enlarged. 



Cosmopolitan. Recorded by Hincks and by O'Donoghue from a num- 

 ber of localities in British Columbia, and by Robertson from Lime Point 

 and San Pedro, southern California. 



