NO. 5 OSBURN : BRYOZOA 11 



aperture which is narrowed at the distal end. The avicularia are inter- 

 zooecial but often appear as if placed on the proximal gymnocyst; they 

 are small and have a short-triangular or rounded mandible. The ovi- 

 cells are endozooecial. 



The species was described from Curagao and later found off the south 

 shore of Porto Rico. 



Distribution.— ?>t^t{om Al-39, A14-39, A27-39, A30-39, A32-39, 

 A42-39, At502, and At505. These stations place the locations at Cale- 

 donia Bay, Panama; Cape la Vela, Colombia; Cubagua, Coche, Marga- 

 rita and Aruba Islands at shore to 23 fms. 



Family LunulariidaC Levinsen 1909 



Genus VIBRAGELLINA Canu and Bassler, 1917 



The genus is characterized by the presence of comparatively large 

 vicarious vibracula which are prominently auriculate, one side of the 

 chamber being raised and curved over the aperture. Canu and Bassler 

 (1917: 14) placed the genus in the family Hincksinidae, but Hai-mer 

 (1926:264) places it in the Lunulariidae, "its vibracula scattered in 

 the zoarium, not alternating with the zooecia in the longitudinal rows; 

 but in other respects it hardly differs from Setosellina" which appears to 

 be the correct view. 



Vibracellina caribbea, new species 

 Plate 1, Figs. 1-2 

 The zoaria form very small colonies encrusting tiny pebbles, shell 



fragments, etc. Among more than 125 specimens the largest measured 

 only 3 mm. The zooecia are alternated somewhat irregularly by the 

 vibracula. The ancestrula is similar in size and details of structure to 

 the later zooecia and produces 6 to 8 buds, one or two of which are often 

 vibracula. 



The zooecia are pale yellowish with the ectocyst, white and glisten- 

 ing when denuded ; distinct and separated by a groove of varying width ; 

 the mural rim raised, thin and finely granulated except on the distal 

 border where it is more elevated. The roughly granulated descending 

 cryptocyst is continued along the sides to the region of the operculum and 

 occasionally forms a minute proximal shelf. The gymnocyst is small, 

 smooth and shining, often vestigial. The ectocyst covers all of the zooec- 



