188 ALLAN HANCOCK PACIFIC EXPEDITIONS VOL. 14 



the basis of a single lunate suboral pore. However, there is too much 

 variation in the number, size and form of these pores to be of specific 

 value; often there is a single larger pore, which may be lunate in form 

 (innominata) , but which is more often round and varies greatly in size; 

 again instead of a single pore there may be 2 to 4 smaller ones, and the 

 two near the middle may be partially united to form a dumb-bell shaped 

 central pore. 



The vicarious avicularia are variable in size and number, the mandi- 

 ble usually long triangular, but may be hastate in form (var. flabellifera 

 Kirkpatrick). Several fossil varieties have also been given names, and 

 Canu and Bassler (1923:98, 90) list var. scripta Reuss, and var. rare- 

 costa Reuss from the Pleistocene of California. 



It is a cosmopolitan species. Hincks and O'Donoghue listed it, in the 

 typical form, from a number of British Columbia localities. 



In the Hancock collections it appears abundantly, 59 stations, from 

 the coast of Oregon south to the Galapagos Islands and the coast of Peru, 

 shallow water down to 136 fms. 



\ijh Colletosia bellula new species 

 Plate 29, fig. 1 



Zoarium forming small white, glistening colonies on shells and peb- 

 bles. The largest colony observed was only two and one-half mm across 

 and those less than two mm may be mature with ovicells. 



Zooecia separated by broad, deep sulci ; moderate in size, 0.35 to 0.50 

 mm long ; the gymnocyst is scarcely visible, nearly the whole front being 

 covered by the pericyst, which consists of 6 or 7 pairs of costulae which 

 radiate toward the center. Between the costulae are rows of about 8 slit- 

 like lacunae; the outer ends of the costules are only slightly elevated. 



The aperture is decidedly lepralioid in form (0.12 mm long by 0.08 

 mm wide) , rounded anteriorly, with a pair of large "cardelles," proximal 

 to which is a broad transverse poster with a nearly straight border. The 

 apertural bar is slightly raised to form a thin, smooth lip and distal to 

 the cardelles a low thin peristome extends around the aperture; 2 to 4 

 small oral spines are present in young zooecia but these soon disappear. 



Another striking character, in addition to the form of the aperture, 

 is the pair of minute, pedunculate avicularia, one on either side opposite 

 the distal end of the aperture ; the mandible is triangular, pointing more 

 or less inward and forward. 



The primary ovicell is small (about 0.15 mm in either dimension), 

 smooth, hemispherical and appears to be closed by the operculum ; it soon 



