NO. 3 OSBURN : EASTERN PACIFIC BRYOZOA CYCLOSTOMATA 617 



Pellicle. A thin calcareous layer. 



Proancestrula. A rounded knob formed by the metamorphosis of the 

 larva, which buds of? the first tubule of a colony. 



Peristome. The projecting end of a tubule (autozoid). Not homol- 

 ogous with the peristome of Cheilostomata. 



Radicle. Root-like or pedunculate structure for attachment. 



Radii. Radiating series of tubules, especially in lichenopores. 



Rhizoid. See radicle. 



Subcolony. Branches or areas similar to the primary zoarium pro- 

 duced by budding of the zoarium, often very numerous in the licheno- 

 pores. 



Tubule. The main part of a zooecium which contains the polypide, 

 usually embedded and ending in a "peristome." 



Zoid. A functional nutritive individual. 



Division I. TubuHpOrina Hagenow, 1851 

 (Acamptostega Borg, 1926) 



This group appears to be the most primitive among recent Bryozoa, 

 as noted by various authors. The zoarium, whether it remains adnate 

 or becomes erect, is always adnate at first, the first tubule arising later- 

 ally without a joint from the ancestral disc and attached for most of its 

 length; and at least a few daughter tubules have this position. The 

 resulting zoaria may take almost any form, uniserial or broadly flabellate, 

 flat or contorted, semierect or erect, and sometimes profusely branched. 

 The apertures are always on the frontal side, with the exception of the 

 Entalophoridae, where they are distributed evenly around the erect 

 stem. The ovicells vary from simple pyriform expansions of the middle 

 portion of the gonozoid to very broad, sometimes lobate, expansions 

 which may cover considerable areas of the zoarium ; and frequently they 

 surround and enclose the erect portions of neighboring tubules. In 

 Entalophora and Fasciculipora the ovicells are narrow and greatly 

 elongated. 



Key to the Families of Tubuliporina 



1. Zoaria adnate or more or less erect, the apertures opening 



only on the frontal side 2 



Zoaria erect, the zooecial tubes forming cylindrical stems with 



the apertures opening on all sides Entalophoridae 



