144 THE ANATOMY OF INVERTEBRATED ANIMALS. 



Fig. 30. — Corallium rubrum (after Lacaze-Duthiers ^). 



I. The end of a branch with A, B, C, three anthozoSids in different desrees of ex- 

 pansion ; k, the mouth ; a, that part of the coenosarc which rises into a cup 

 around the base of each anthozoOid. 



II. Portion of a branch, the coenosarc of which has been divided longitudinallj' and 

 partially removed; B, B\ B'\ anthozooids in section; B^ anthozoOid with ex- 

 panded tentacles; k, mouth ; m, gastric sac ; e, its inferior edge; j^ mesenteries. 



J?', anthozoOid retracted, with the tentacles {d) drawn back into the intermesenteric 

 chambers; c, oriftcea of the cavities of the invaginated tentacles ; e, circum-oral 

 cavity ; 6, the part of the body which forms the projecting tube when the antho- 

 zoOid is expanded ; a, festooned edges of the cup. 



B" ^ antliozoOid, showing the transverse sections of the mesenteries. 



-4, A, coenosarc, with its deep longitudinal canals (/'), and superficial, irregular, 

 reticulated canals (A). P, the hard axis of the coral, with longitudinal grooves 

 fj7) answering to the longitudinal vessels. 



III., IV. Free ciliated embryos. 



1 " Ilistoire Naturelle du Corail," 1864. 



