BRYOZOA 



253 



2. GEMELLARIA Savigny. Colony erect, branching; zooecia joined 

 back to back, the pairs rising from the top of one another; aperture 

 large: several species. 



G-. loricata (L.). Colony bushy, up to 20 cm. high, brown in color, 

 composed of long, straight branches; zooecia narrowed below; aperture 

 oval: in northern seas; Vineyard Sound northwards; Alaska; Europe. 



6 



FAMILY 3. CELLULAE1IDAE. 



Colonies erect, dichotomously branched ; zooecia in 2 or more rows in 



the same plane; avicularia and vibracula (Fig. 411), or the former alone, 



almost always present; opening not terminal, 



usually armed with spines and usually with 



an operculum: 8 genera. 



1. MENIPEA Lamouroux. Colony jointed, 



zoo3cia oblong, widest above, attenuated down- 

 ward, usually with sessile avicularia and 



ooacia; no vibracula: about 20 species, 7 



American, mostly on the Pacific coast. 



M. ternata (Ellis and Solander). Colony 



in small tufts, 25 mm. high; zocecia in 2 rows, 



alternate and arranged in groups of 3; long 



fibers extend from the zooecia: circumpolar; 



Cape Cod northwards from shallow to deep water, on 

 hydroids and shells ; Europe ; Pacific coast. 



2. CABEREA Lamouroux. Colony not jointed; 

 zooecia in 2 or more rows, quadrangular or ovate, with 

 a very large opening; sessile avicularia and enormous 

 vibracula as well as long, clasping fibers present : about 

 15 species, 1 American. 

 C. ellisi (Fleming) (Fig. 412). Colony with numerous branches, 25 



mm. high; zooecia in 2 to 4 rows and quadrangular; vibracula very long 



and serrate: circumpolar; Vineyard Sound northwards, from shallow to 



deep water; often common; Europe; Alaska. 



Fig. 411 

 A, an avicularium 



B, a vibraculum 

 (Delage et He"rouard). 

 1, nerve ; 2, muscles. 



Fig. 412 



C altered ellisi 



(Osburn). 



FAMILY 4. BICELLAEIIDAE. 



Colony erect and branching; zooecia obliquely placed in 2 or more 

 rows and conical or rectangular; stalked avicularia usually present and 

 no vibracula; ooecia at the upper end of the zooecia: 16 genera. 



1. Bi CELL ARIA Blainville. Zooecia cornucopia-shaped, loosely joined 

 together and directed obliquely sideways: about 15 species. 



