i8 THE VOYAGE OF H.M.S. CHALLENGER. 



zone, a small ill-defined pit exists. The poriferous zone is narrow, the paii-s of pores 

 separated by high ridges are somewhat wider in the central part. The median ambulacral 

 area is wider than the poriferous zone. The ambulacral plates are separated from the 

 poriferous zone by a vertical row of distinct secondary granules. The lower part of the 

 ambulacral plates is occupied by minute granides, leaving distinct bare spaces forming- 

 small rectangular pits, which alternate for the whole height of the ambiilacral area (PI. I. 

 fig. 13). The larger granules carry short, slender, sharp papillae, while the miliary granules 

 carry diminutive papillje scarcely equal in length to the height of the ambulacral 

 plates. The ocular plates are heart shaped. The genital plates are heptagonal, separated 

 by large pointed plates from the anal system, which extends to the ocular plates. The 

 genital openings are large, situated nearer the centre of the plates than the edge. The 

 anal system is covered by a single row of ten larger plates adjoining the genital plates, 

 with smaller irregularly-shaped plates in the centre. The whole abactinal system is 

 closely covered with indistinct tubercles carrying short sharp jjapillae, somewhat largest 

 around the anal opening. The outer part of the coronal plates not occupied by the 

 scrobicular tubercles is closely packed with minute granules carrying diminutive papillse 

 similar to those of the median ambulacral space. The colour of the spines of alcoholic 

 specimens is white; the papillae round the base of the primaries are light reddish-yellow. 

 This species is remarkable for its small actinal opening. 



In a specimen measuring 27 mm. in height, in which there are seven primary 

 tubercles, the diameter of the test is 26 mm. ; the diameter of the actinal system, 

 1 1 mm. ; and that of the abactinal system, 1 3 mm. The length of the longest curved 

 primary spine is 56 mm. 



The ornamentation of the sutures of this species, extending over the greater part of 

 the coronal plates, shows the affinities of Goniocidaris with Temnocidaris of Cotteau (not 

 A. Agassiz); see Pal. Frangaise, PL 1085-1087 (bis). 



The short-stemmed globular-headed interambulacral pedicellarise of Goniocidaris 



Jlorigera (PI. XLII. fig. 3) are remarkable for the great size of the basal part of the 



head and the small open foramina left between the terminal prongs of the head. 



These are larger than we usually find them in the corresponding pedicellarise of other 



Cidaridse. 



The shape of the long-stemmed narrow-headed ambulacral pedicellarise is shown 

 on Plate XLII. fig 2. On the test the globular-headed short-stemmed pedicellarise 

 are more elongate (PL XLIV. fig. 5), and the terminal prong of the valves is 

 stouter. 



Station 192. September 26, 1874. Lat. 5° 42' S., long. 132° 25' E. ; 129 fathoms ; 

 mud. Ki Islands. 



Station 204. November 2, 1874. Lat. 12° 43' N., long. 122° 10' E. ; 100 fathoms 

 and 115 fathoms; mud. 



