tective sheath; digestive tract of individual animals U-shaped, with the 

 mouth and anus near together- — Bryozoa or Moss Animals 14. 



3. Spicules spine- or quill-like 



Spongilh Lamarck 

 Some of the gemmule spicules birotulate (formed of a rod with a disc 

 or cap on each end, resembling a spool or bobbin) 4. 



4. Opening to gcmmule (reproductive bud) spout-like, with one or more 



lilaments or tendrils from the end 

 Carterms Potts 

 No tendrils or filaments from the openings to the gemmules 5. 



5. Gemmules with two kinds of birotulate spicules 6. 

 Gemmules with one kind of birotulate spicules, which may vary some- 

 what in size 7. 



6. Flesh spicules quill-like or absent 



Heterovieyenia Potts 

 Flesh spicules star-shaped 



Aster onieyenia Annandale 



7. With the disc-shaped ends of the birotulate spicules with smooth margins 



Trochospongilla Vejdovsky 

 Ends of birotulate spicules with serrated margins 8. 



8. Flesh spicules star-shaped 



Dosilia Gray 

 Flesh spicules not so, often absent 

 Ephydatia Lamouroux 



9. Branching, plant-like, colonial animals; tentacles scattered over the bodies 



of the individual animals; colonies stationary, attached to sticks, vegeta' 

 tion, etc. 



Cordylophora lacustris Allman 

 Single animals, often with one or more sprouts or buds; tentacles, if 

 present, in a ring around the mouth area 10. 



10. With two generations differing greatly in appearance; the common, sexual 

 generation is bowl-shaped, with a ring of tentacles around the mouth 

 area, and is free-swimming; the less familiar, asexual generation is 

 very small, cylindrical (often with sprouts or buds) , without tentacles, 

 and attached to plants, sticks, etc. 



Craspedacusta ryderi (Potts) Medusa or Jelly-fish 

 {Craspedacusta sowerhyi Lankester) 

 No alternation of generations; body cylindrical (excepting buds or sexual 

 organs in the body wall), with a ring of tentacles around the mouth; 

 usually attached to water plants, but capable of free motion — Hydras 



11. 



1 1 . Animal bright green in color 



Chlorohydra viridissima (Pallas) Green Hydra 

 (Hydra viridis Linn.) 

 Body whitish, brownish or reddish 12. 



55 



