CORALS AND CORAL MAKERS. 



6i 



In one family of this tribe the polyps form red calcareous 

 tubes ; sometimes a slender, creeping tube, with polyps at 

 intervals, as in a species referred by the author to the genus 

 Aulopora ; but generally 

 vertical tubes, grouped 

 into large red masses, 

 called, popularly, Orga?i- 

 pipe coraL A portion of 

 one of the latter — Tiibi- 

 pora syringa D. — is re- 

 presented in the first of 

 the annexed figures, with 

 its expanded polyps ; 

 and a polyp from the 

 group much enlarged in 

 the sfcond figure. The 

 papillse of the fringe are 

 arranged closely together 

 in a plane, so that it is 

 not at first apparent that 

 there is a fringe. The 

 third figure represents, 

 enlarged, the polyp of 

 another Feejee species, 

 the Tubipora fiinbriata 

 I). Such coral masses 

 are sometimes a foot or 

 more in diameter, and 

 the living zoophyte, with 

 its lilac or purple polyps 

 fully expanded, looks 

 much like a large cluster 

 of flowers from a lilac bush, 

 plates at intervals. 

 . 2. Gorgo/iia tribe, or Gorgonacea. — The following figure re- 

 presents a species of this tribe from the Kingsmill or Gilbert 

 Islands. It is one of the net-like or reticulated species, the 



The tubes are united by cross 



