MOLLUSCOIDA. 



Lophophore present. Mouth and anus closely approximated. 

 Coelom usually present. 



CLASS 1. Polyzoa. 



Usually colonial. Zooids of small size and pro- 

 tected by a firm cuticle. 

 Subclass 1. Ectoprocta. 



Anus outside of the lophophore. 

 Order 1. Gymnolsemata. 



Marine. Circular lophophore. No epistome 

 present. (Bugula, Membranipora.) 

 Order 2. Phylactolsemata. 



Fresh -water. Horseshoe -shaped lophophore. 

 Epistome present. (Plumatella, Pectinatella.) 

 Subclass 2. Endoprocta. 



Colonial or solitary. Anus and mouth both in- 

 side of the lophophore. (Loxosoma, Pedicellina.) 

 CLASS 2. Phoronida. 



Marine. Solitary. Lophophore horseshoe-shaped 

 with each end coiled. (Phoronis.) 

 CLASS 3. 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. 



The colonies are very common in shallow water along shore, 

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

 aid of a glass-bottomed pail in the positions they occupy on the 



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