MOLLUSCOIDA. 



Lophophore present. Mouth and anus closely approxi- 

 mated. Coelom usually present. 



Class 1. Polyzoa or Bryozoa. 



Usually colonial. Zooids of small size and pro- 

 tected by a firm cuticle. 

 Subclass 1. Entoprocta. 



Colonial or solitary. Anus and mouth both in- 

 side lophophore. Epistome present. Tentacles 

 not retractile. Stalk contractile. (Loxosoma, 

 Pedicellina.) 

 Subclass 2. Ectoprocta. 



Colonial. Anus outside lophophore. Mouth 

 inside it. Tentacles retractile. Stalk not re- 

 tractile. 



Order 1. Gymnolaemata. 



Recent, marine. Lophophore circular. Epi- 

 stome absent. (Crisia, Bugula, Flustrella, 

 Membranipora, Lepralia, Schizoporella.) 



Order 2. Phylactolsemata. 



Fresh-water. Lophophore horseshoe-shaped. 

 Epistome present. (Plumatella, Pectinatella.) 

 Class 2. Brachiopoda. 



Marine. Solitary. Bivalve shell. Usually at- 

 tached by a peduncle. 



Order 1. Inarticulata. 



Valves not united by a hinge. (Lingula.) 



Order 2. Articulata. 



Valves hinged. Usually with a shelly loop to 

 support the lophophore. (Terebratulina.) 



POLYZOA. 



BUGULA. (Sp.) 



The colonies are very common in shallow water along shore, 

 attached to rocks and piles. They may be examined with the 



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