CLARK: THE CIDARIDAE. 221 



Stereocidaris leucacantha. 



Stereocidaris leucacantha A. Agassiz and Clark, 1907, Haw. Pac. Ech. Cid., p. 23. 



Plates 15, 32, Haw. Pac. Ech. Cid., A. Agassiz and Clark, 1907. 



Although this Hawaiian species, collected at a number of stations by the 

 " Albatross," is very close to grandis in many ways, the two are easily distin- 

 guished at a glance, and no intermediate specimens have been seen. The largest 

 specimen is 57 mm. h. d. The color is somewhat variable, that of the test and 

 secondaries ranging from almost yellowish-white to deep purplish-gray ; there is 

 usually a decidedly purple cast actinally. The primaries are longer and more 

 slender than in grandis (the thickness only 4 or 5% of the length), and are 

 white when clean. The fully grown ones almost always have the collar deep 

 purple, sharply contrasted with the white neck. In many specimens the seconda- 

 ries show an evident green tinge. 



Stereocidaris sceptriferoides. 



Cidaris (Stereocidaris) sceptriferoides Doderlein, 1887, Jap. Seeigel, p. 5. 

 Stereocidaris sceptriferoides Doderlein, 1887, Jap. Seeigel, p. 42. 



Plate 2, figs. 12-17, Jap. Seeigel, Doderlein, 1887. 



This species, although it appears to be very rare, is well characterized. The 

 globiferous pedicellariae are very slender, the valves often have a conspicuous 

 end-tooth, and the opening may be very long m id narrow. The only known 

 specimens of this species were taken in Japanese waters. 



ANOMOCIDARIS. 



Anomocidaris A. Agassiz and Clark, 1907, Haw. Pac. Ech. Cid., p. 30. 



Test rather flat, vertical diameter about .50 h. d., but sometimes, through eleva- 

 tion of abactinal system, conspicuously rounded-eonical ; vertical diameter from 

 centre of anal system in such eases being about .60 h. d. ; coronal plates 7-9; areo- 

 lae abactinally small, very shallow and indistinct, on the uppermost plates practi- 

 cally wanting, but at ambitus and below deeply sunken and merging together near 

 aetinostome; median interambulacral area covered with small tubercles, not at all 

 bare or sunken, but sutural lines distinct; ambulacra about .30 of interambulaera ; 

 poriferous zones not deeply sunken ; median ambulacral area with two or three 

 series of tubereles on each side, inner much smaller and more or less incomplete; 

 vertieal sutural line usually distinct; pores nearly horizontal; distance between 

 two not quite equal to diameter of pore. Abactinal system moderate, about .47 h. d. ; 

 anal system small, less than .40 of abactinal system and composed of only about 

 20 plates and grains; oculars rather small and genitals very widely in contaet with 

 each other. Whole abaetinal surface more or less densely covered with very small 

 secondaries, miliaries, and pedicellariae. Aetinostome small, .35 h. d., only about 

 .75 of abactinal system. Primary spines slender, 1-1.50 h. d.; thickness 3-5% of 

 length; cylindrieal with longitudinal series of minute granules, sometimes nearly 

 smooth, often flattened and widened at tip ; actinal primaries very variable, some- 



