Boone, Echinoidea, Cruise of "Alva'* 1931 249 



Material examined: Two specimens from anchor chain, 

 Seba-Seba Bay, South Brother's Island, Dutch East Indies, col- 

 lected by the "Alva." 



Discussion: Dr. Mortensen (1928) presents critical diagno- 

 sis of both the typical and varietal forms of this species and con- 

 cludes that they are both more or less distinct varieties of one 

 highly polymorphous species, each form of which has an extensive 

 range of individual variation. The variety annvlifera is readily 

 distinguished by its distinctive coloring of the primary and sec- 

 ondary spines, the primaries being conspicuously banded and 

 much longer and slenderer than the typical baculosa; the collar 

 of the primaries is also definitely longer in annulosa. The num- 

 ber of ambulacral plates corresponds to the interambulacral plates. 

 The denuded test of annvlifera is pearly white. 



The "Alva" specimens are much encrusted with barnacles 

 and Bryozoa and entwined with several specimens of an interest- 

 ing ophiuran. The specimens have been preserved in alcohol for 

 four years, so that the original color is gone, but the banded color 

 pattern is retained. 



References: Cidarites annulifera, Lamarck, J. B., Hist. Nat. 

 Anim. sans Vert., 1816, t. Ill, p. 57. 



Cidaris annulifera, DE LORIOL, P., Mem. Soc. Sc. Neuchatel, t. V, 

 1873, p. 25, pi. 3. 



Prionocidaris baculosa variety annulifera, Mortensen, Th., 

 Monogr. Echinoidea I Cidaroidea, 1928, p. 443, pi. 45, figs. 1, 

 2 ; pi. 46, pi. 51, fig. 2 ; pi. 53, figs. 4-8 ; pi. 73, figs. 14, 15 ; pi. 

 87, fig. 5 (with full diagnosis and extensive literature ci- 

 tations). 



Genus: PHYLLACANTHUS Brandt 

 Phyllacanthus imperialis (Lamarck) 



Plates 81 and 82 



Type : Lamarck cited the Red Sea and the Mediterranean Sea 

 as the type localities of his material and also referred to Seba's 

 Echinometra altera digitata, Seba Mus. 3, tab. 13, fig. 3. Lamarck's 

 specimens are in the Paris Museum. 



Distribution : This strikingly beautiful urchin is widely dis- 

 tributed all over the Indo-Pacific region from the Red Sea down 



