GENERAL ZOOLOGY 





Siphonogl>'ph 



/ HI, I 



Fig. 10.13. Metridmm dianlhus, a 

 sea anemone. .4, oral view of a 

 lare;e specimen, showing oral disk, 

 mouth, tentacles, and siphonoglyph. 

 B, a mature individual attached to 

 the shell of a mussel; the young in- 

 dividuals about its base were pro- 

 duced asexually by "pedal lacera- 

 tion," developing from small pieces 

 detached from the base of the 

 parent. C, diagrammatic longi- 

 tudinal section; the so-called com- 

 plete septa extend from the body 

 wall to the pharynx, and incomplete 

 septa have free edges in the coelen- 

 teron, containing numerous gland 

 cells and nematocysts. The acontia 

 are filamentous continuations of 

 these septal edges. (.4 and B, photo- 

 graphs by Bassett Maguire, Jr.; C, 

 redrawn from L. H. Hyman, The 

 Invertebrates: Protozoa through Cteno- 

 phora, copyright 1940 by McGraw- 

 Hill Book Co., Inc., printed by 

 permission.) 



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