BETOZOA 251 



ter, crowded together and radiating from the center to the edge, and 

 with the outer ends erect: Long Island Sound to Greenland, on algae, 

 etc., in shallow water; Europe. 



T. fimbria Lamarck. Colony 12 mm. in size ; fan-shaped and lobed ; 

 zooecia slender, not raised at the outer ends, and wrinkled transversely: 

 in shallow and deep water; North Atlantic; Europe. 



T. liliacea (Pallas) (T. pruinosa Stimpson). Colony about 9 mm. 

 high and white, or often purple and punctate; branches in same plane: 

 Atlantic coast; Europe; on shells, hydroids, etc. 



FAMILY 3. LICHENOPORIDAE. 



Colony discoid, flat, or more or less raised, forming either a simple 

 disc or several confluent ones; zooecia partially erect, forming distinct 

 rows which radiate from a large central free area and are not close 

 together, the spaces between being porous : 2 genera. 



LICHENOPORA Defrance (Discoporella Gray). Colony thin and lami- 

 nate, sometimes composite: about 30 species. 



L. hispida Fleming. Single disc up to 6 mm. in diameter; each indi- 

 vidual with 10 short tentacles: North Atlantic, on shells, algae, etc., from 

 moderate to great depths; often common; Europe. 



L. verrucaria (Fabricius). Disc 3 mm. in diameter; zocecium with 

 a rib : North Atlantic, south to Long Island Sound ; common ; Europe. 



SUBORDER 2. CHILOSTOMATA.* 



Colonies either erect or recumbent; zooids tubular, oval, or rectan- 

 gular, and calcareous, horn-like, or membranous, the opening usually not 

 terminal and usually closed by a movable operculum (Fig. 406) ; avicu- 

 laria, vibracula, and ooecia usually present: about 36 families, all being 

 marine, including the majority of Bryozoa. 



Key to the families of Chilostomata here described : 



Oj, Colony not incrusting or foliaceous but usually dendritic. 

 &! Colony composed of a creeping base and erect shoots ; no avicularia or 

 vibracula. 



G! Zooids rising separately from the base 1. ^ETEIDAE 



c 2 Erect shoots composed of many zooids each 2. EUCBATEIDAE 



& 2 Colony dendritic, without a creeping base. 

 c x Avicularia sessile and fixed, 

 dj Colony slender. 



e, Branches flattened 3. CELLULAKIIDAE 



e 2 Branches cylindrical 5. CELLABIIDAE 



d t Colony foliaceous 6. FLUSTBIDAE 



c 2 Avicularia pedunculate and jointed 4. BICELLAEIIDAE 



* See "Non-incrusting Chilostomatous Bryozoa of the West Coast," by Alice 

 Robertson, Univ. of Cal. Pub., Vol. 2, p. 235, 1905. "The Incrusting," etc., by same, 

 ditto, Vol. 4, p. 253, 1908. "The Chilostomatous Bryozoa," by G. M. R. Levinson, 1909. 



