MOLLUSCOIDA. 



Lophophore present. Mouth and anus closely approximated. 

 Ccelom 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. Gymnolaemata. 



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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