Hydroid Skeletons and Fluid Flow

  • Gordon R. Murdock


Most hydroid colonies are encased in a tubular chitinous exoskeleton, the perisarc. Hyman (1940, p. 402) observes of the perisarc that “On stems it usually forms groups of rings or annulations at definite points related to the branching... The function of these is obscure, but it is generally supposed that they lend flexibility.” Perusal of the literature and conversations vith biologists studying hydroids suggest that the annular regions on hydroid perisarc are no better understood now than in 1940. Indeed, little more is known of the perisarc itself or of the skeleton which it forms.


Branch Point Local Buckling Annular Region North Carolina 27706 Flexural Stiffness 


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Copyright information

© Springer Science+Business Media New York 1976

Authors and Affiliations

  • Gordon R. Murdock
    • 1
  1. 1.Department of ZoologyDuke UniversityDurhamUSA

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