Subfamily SPONGILLINAE 



Fresh-water sponges, with body spicules straight or 

 slightly curved, gemmule spicules plain or birotulate; re' 

 production asexual, by gemmules 

 Seven genera — Spongilla Dosilia 



Ephydatia Trochospongilla 



Heteromeyenia Carterius 



Aster omeyenia 

 Phylum COELENTERATA 



Radially symmetrical animals with a gastrovascular cavity and no 

 coelom; middle body layer primarily noncellular; body, and especially 

 the tentacles, with nettle cells or nematocysts 

 Class HYDROZOA 



Hydroid stage usually evident; medusa usually minute or reduced 

 to sporosac 

 Order HYDRARIAE 



Elongate, cylindrical animals, attached or free'floating; mostly in 

 fresh water; no medusae 

 Three genera — Chlorohydra 

 Hydra 



Fclmatohydra 

 Order TUBULARIAE 



Colonial forms; hydranth without hydrotheca; no medusa in fresh' 

 water genus 



One genus — Cordylophora 

 Order TRACHOMEDUSAE 



Hydroid stage omitted or minute; medusa with a velum 

 One genus — Craspedacusta 

 Phylum BRYOZOA 



Colonial, aquatic animals; with tentacles on a ridge around the mouth; 

 digestive tract U-shaped; with coelom 

 Class ENTOPROCTA 



Anus within circle of lophophore; lophophore circular, with a single 

 row of tentacles which cannot be completely retracted 

 Family URNATELLIDAE 



Each colony consisting of a few zooids which rise from a com- 

 mon disc; stalks long, jointed, branching 

 One genus — Umatella 

 Class ECTOPROCTA 



Anus outside lophophore, which can be completely retracted 

 Order GYMNOLAEMATA 

 Lophophore circular 



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