BEYOZOA 261 



A. dichotoma (Verrill) (Fig. 427). Colony 5 cm. or more high and 

 white in color, repeatedly forking, a short, dark-brown segment being 

 at the base of each fork; zooids crowded together spirally in groups of 

 6 to 12 each: New Jersey northwards, on algae, rocks, etc., in shallow 

 water; often common. 



FAMILY 4. VALKEEIIDAE. 



Colony branching and erect or recumbent and creeping; tentacles 

 8 in number, 2 of which are bent outwards towards the side and 6 are 

 erect; zooecia contracted below: 1 genus. 



VALKERIA Fleming. With the characters of the family: 4 species. 



Fig. 427 Fig. 428 Fig. 429 



Fig. 427 Amathia dichotoma (Osburn). Fig. 428 Valkeria uva (Osburn) 

 Fig. 429 Paludicella ehrenbergi. 



V. uva (L.) (Fig. 428). Colony composed of delicate jointed tubes, 

 which creep over seaweed, hydroids, or shells, or may stand erect to a 

 height of 5 to 10 cm. giving off paired branches ; zooids in thick clusters, 

 which are principally at the base of the branches atfd on them: from 

 New Jersey northwards, in shallow water; Europe. 



FAMILY 5. PALUDICELLIDAE.* 



Colony with a horn-like or membranous cuticula and composed of 

 delicate, jointed, branching, recumbent or partly erect tubes, which creep 

 over stones and sticks in slow streams and fresh-water ponds : 2 genera. 



Key to the genera of Paludicellidae : 



Oi Zooids recumbent, not rising from stolons - 1. PALUDICELLA 



a 2 Zooids erect, rising from stolons 2. POTTSIELLA 



1. PALUDICELLA Gervais. Colony consists of series of club-shaped 

 zooids placed end to end and separated from one another by partitions ; 

 opening lateral; branches usually paired; no statoblasts present but 

 hibernacula or winter buds which persist when the rest of the colony 

 has died: 1 species. 



P. ehrenbergi van Beneden (Fig. 429). Colony recumbent or partly 

 erect ; length of zooid 2 mm. ; number of tentacles about 16 : cosmopolitan. 



* See "Observations on Budding in Paludicella and Some Other Bryozoa," by 

 C. B. Davenport, Bull. Mus. Comp. Zool., Vol. 22, 1890. 



