98 " ENDEAVOUR " SCIENTIFIC RESULTS. 



Mr. Agassiz's application of the name bispinosa to this species 

 cannot be maintained since de Loriol's restriction of Lamarck's 

 name to the species Mr. Agassiz called annulifera has several 

 months' priority over Mr. Agassiz's selection. The latter 

 being left thus without a name, Doderlein courteously pro- 

 posed to call it agassizii. When at the Austrahan Museum in 

 November, 1913, I was surprised to find that Ramsay's type 

 of PhyllacantJius australis is a fine example of the Sea-urchin 

 Mr. Agassiz and I have called Stephanocidaris bispinosa. It 

 is not strange that no one has suspected it hitherto, for 

 Ramsay gives virtually no description but rehes on three 

 photographs to make clear the specific characters. The whole 

 nomenclatural tangle is now fairly well cleared up, and 

 apparently all living students of the recent Echini are agreed 

 as to the proper use of Lamarck's names for cidarids, even 

 though we still disagree as to generic divisions. 



The present series of P. australis ranges from 27 to 73 mm. 

 in test-diameter, horizontally (h.d.) ; the specimen with h.d.= 

 27 mm., has primary spines 67 mm. long or 2.5 h.d., while in 

 the big individual they are only 60-65 mm. long or less than 

 h.d. Evidently 65-70 mm. is the full length of the spine for 

 this species, and growth ceases when that length is attained, 

 though the test may continue to grow indefinitely. The 

 primary spines when young are purple and smooth ; they 

 soon develop sharp teeth along the sides, and with this 

 development the spine becomes somewhat flattened ; at least 

 the oral side is more or less flattened, the aboral side tending 

 to become carina te ; the spine is thus almost or quite 

 triangular in cross-section, where widest ; as the lateral teeth 

 increase in size numerous similar but smaller teeth arise, 

 particularly along the aboral side ; with this change in form 

 of the spine there goes an equally great change in colour ; the 

 teeth are greenish and as they increase in number the spines 

 appear to be less and less purple ; as the spine matures it 

 becomes coated with a loose, colourless or whitish calcareous 

 coat which completely masks the remaining purple colour ; 

 then Sponges, Bryozoa, Brachiopods, Lamellibranchs, Worm- 

 tubes and Barnacles (but particularly Barnacles) proceed to 

 encrust the adult spines, making them the habitations of 

 small Brittle-stars and Crustaceans. Many of the old, short 

 actinal primaries (but not the small ones around the mouth) 

 become very flaring at the tip in old individuals ; thus a spine 

 3.3 mm. in diameter near the middle may be almost 5 mm. 

 across the obliquely truncate and almost flat tip. The white 

 spots on the collar of the primaries appear as soon as the 

 collar is formed ; they are always visible, but the distinctness 



