PRESIDENTIAL ADDRESS. 



67 



Fig. 33. Coscinasterma 

 common starfish. 



another 



is irregular in the 

 length and number 

 of its finger-shaped 

 limbs, it is coloured 

 with sepia and sage 

 green in patches and 

 outlined by a margin 

 of vivid orange red. 

 Local starfish are 

 not regarded as a 

 pest by oyster culti- 

 vators as are those 

 of European Seas. 1 



Neighbours of these are a dark-purple urchin with dense, 

 short, fluted spines, Toxocidaris erythrogrammus, 2 which 

 carves, each for itself, a cup in the stone (Plate VII, fig. 11) 

 like that in which the European Strongylocentrotus lividus 

 entrenches itself. 3 Sometimes this urchin is concealed 

 under scraps of shells or stones held over it like shields by 

 the pedicellarise. Several large gasteropods such as Thais 

 succinta, Charonia rubicunda, Cymatium spengleri, Turbo 

 stamineus and Haliotis naevosa, share such retreats. 



Along the edge of this gutter in the Galeolaria reef and 

 exposed at low water is the sea-anemone, Oulactis muscosa* 

 (fig. 34) which prefers a crack into which it can withdraw 

 when disturbed. It enjoys the fullest exposure to the light 

 and expands to a diameter of three inches. Though a fine 

 species for this latitude, it is a pigmy compared to the giant 

 anemones on the Great Barrier Reef, which have a spread 

 of two feet. The trunk of the Oulactis is beset with 



1 Schiemenz, Journ. Mar. Biol. Assoc, iv, 1896, p. 266. 



2 Mortensen, Danish Ingolf Expedition, iv, pt. 1, 1903, p. 139. 



3 Joubin, Bull. Mtts. Oceanogr. Monaco, 71, 1906, p. 19, fig. 18. 

 * Andres, Faun. Flor. Gulf Napl., ix, 1884, p. 291. 



