Erect, finely branched & delicate; 3-5 cm tall; side branches <1 mm across; white to cream. 

Common, but patchy; on rocks among red algae & other sessile invertebrates.

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Erect; branches flattened in cross section 2-4 mm across. Pale yellow or tan. Colonies 5-8 cm thick & >30 cm across in some sites.

Moderately common, but patchy in Monterey; provides habitat for many kinds of small motile  invertebrates.

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Chitinous leathery folded sheets, tan; forms rounded fan-like encrustations on algae; colony appears fuzzy when zooids' large lophophores are extended.

Common, usually encrusting vegetative fronds of Cystoseira in Monterey region.

Tiny tubular zooids (<0.5 mm tall) interconnected by basal stolons, growing on algae or as minute branching colonies. Appears as a white fuzz or a very delicate hydroid to unaided eye.

Common but inconspicuous; especially on wharf pilings & other fouling communities.

Encrusting on kelp or other algae; colonies translucent white; zooids rectangular with clear frontal membrane.

Abundant but variable in time and space. On kelp blades as well as smaller algae.

Encrusting on rocks, colonies orange with darker orange or brownish margins; zooids rectangular with clear frontal membrane & dark orange borders (inset). 

Common but inconspicuous on undersides of rocks & in crevices.

Erect bushy colony, 5-8 cm tall;  branches curve slightly inward toward central axis, lightly calcified; dark purple. 

Common in sheltered sites such as wharf pilings, Deep Reef; sporadic in kelp forests in Monterey.

Erect, bushy, 5-8 cm tall; side branches arranged in distinct spirals around central axis; pale orange to tan.  

Spotty but can be common, on rocks in low intertidal and kelp forest depths; also on wharf pilings.

Colony erect & branched, 10 cm tall; branches flattened with two rows of zooids on inward-facing side (biserial); flagella-like vibraculae present. Microscopic examination required to distinguish species.

Moderately common, on rocks with other sessile invertebrates & red algae; also on wharf pilings.

Colony erect & branched, 5-8 cm tall; with dark joints separating sausage-like internodes; giant avicularia with dark mandible (visible only under a microscope). 

Common, but inconspicuous; on rocks among other sessile invertebrates and red algae.

Encrusting, pale yellow with dark yellow margin. 

Common, but inconspicuous, on rock faces and undersides of cobbles & boulders, usually with other encrusting bryozoans & often partially overgrown by neighboring invertebrates or algae.

Encrusting colony, usually on red algae. Glassy white; colonies dioecious with larger female feeding zooids and minute dwarf male zooids. 

Very abundant, especially on low-lying red algae such as Rhodymenia.

Erect to 10 cm tall; branches circular in cross section 3-5 mm diameter; white or cream. 

Very common, on rocks in areas with moderate to strong water motion.

Encrusting colony of thick lumpy brown or gray crusts; possess giant interzooecial avicularia with black mandible (only visible under a microscope). 

Common, especially in protected harbors & wharf pilings.

Encrusting with visible zooids; rose red to pink. 

Common, on rocks, often partially overgrown by other inverts or algae.  Preferred prey of pink hopkinsia nudibranch Okenia rosacea.

Encrusting with large zooids (1-2 mm) visible to naked eye; aperture round with raised collar-like margin; yellow to pale orange. 

Common but inconspicuous; on rocks.

Forms low rounded knobs 4 cm tall; bright orange. 

Common, on rocks interspersed with other bryozoans and sessile invertebrates.

Erect branched colony 5 cm tall; branches cylindrical 2-3 mm diameter & densely packed; pale orange or tan. 

Common, on rocks; colony may cover respectable area; interior of colony provides habitat for many different polychaetes, crustaceans, & other small motile invertebrates.

Encrusting base growing into foliacious sheet-like folds; golden brown to orange; no lace-like perforations in colony. 

Common, growing on rocks and encrusting blades of red algae.

Erect, foliacious, rigid tuft of folded sheets to 10 cm or more across with lace-like perforations throughout colony; bright to pale orange; zooids only on inner faces of folds. 

Abundant, on rocks. Often with juvenile Calliostoma annulatum living on colony.

Encrusting base growing into foliacious folded sheets. Dark red to black; zooecia with large black opercula. Colonies rigid, but fragile; erect portions appear to die back periodically (gray portion in photo).

Increasingly common; fast-growing introduced species; on rocks in kelp forests as well as sheltered sites such as harbors & wharf pilings.