NO. 1 OSBURN : EASTERN PACIFIC BRYOZOA CHEILOSTOMATA 63 



ooecium is an unusual character in Alderinidae. The genus is well repre- 

 sented in the American Tertiary, but no recent species has hitherto been 

 recorded from American waters. 



Type, AH F no. 17. 



Type locality, Hancock Station 1914-39, off Pyramid Cove, San 

 Clemente Island, California, 78-110 fms, encrusting a gastropod shell. 



Genus CALLOPORA Gray, 1848 



Genotype, Flustra lineata Linnaeus. 



Gray's genus was neglected almost entirely for many years until re- 

 established by Norman (1903:588). The characters given by Norman 

 are: front wall entirely membranous, marginal walls more or less thick- 

 ened and crowned with a few or many spines. Ovicell commonly with 

 a rib across the front. Sessile avicularia with acute mandible at the bot- 

 tom of the zooecium and above the ovicell or in a lateral position on one 

 or both sides of the oral opening, or in both positions in the same species. 

 Usually two pairs of lateral and one distal dietellae. 



Canu and Bassler (1920:146) included the tenuirostris group of 

 Waters, but Harmer has established the genus Copidozoum for this 

 group and his judgment is accepted here. This excludes those species in 

 which the avicularia are large, vicarious and replace zooecia in the series. 

 Callopora has been much misunderstood and many species have been listed 

 under this genus which properly belong elsewhere. 



Key to Species of Callopora 



1. Avicularia wanting, accessory distal spines outside of the main 



row whiteavesi 



Avicularia present 2 



2. Lateral (distal) avicularia only 3 



Proximal avicularia present 4 



3. Avicularia minute, marginal, spines long and numerous. . . . 



corniculifera 



Avicularia somewhat larger, spines fewer and shorter. . . . exilis 



4. Proximal avicularia only, single or paired 5 



Both proximal and lateral avicularia present 9 



5. Avicularia large, often curved around the opesia 6 



Avicularia smaller, mandible straight 7 



6. Zooecia well separated, with areolations between. . circumclathrata 

 Zooecia closer together, no interzooecial areolations. . . horrida 



7. Spines 1 to 3, ovicell with a v-shaped area aurita 



Spines numerous 8 



