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



greyish-yellow, and sometimes iri'egixlarly banded with brownish-red patches. The 

 difference in the shape of the plates of the abactinal system readily distinguishes this species 

 from Dorocidaris ixvpillata; the ocular plates are broadly triangular, extending to the 

 edge of the anal system, which is covered by a smaller number of plates relatively larger 

 than in Dorocidaris pcq^illata. The whole abactinal system is covered by finer granules 

 more closely packed than in that species. The ambulacral system is relatively much 

 narrower, both the poriferous zone and the median interporiferous space. The scrobicular 

 area is scarcely sunken, the coronal plates are not high. Otherwise, the test closely 

 resembles that of the Atlantic Dorocidaris ixiinllata, but with less distinct and smaller 

 secondary and miliary tubercles. 



The short-headed long-stemmed ambulacral pedieellarise of Dorocidaris hracteata 

 differ from those of Dorocidaris papillata in being broadest at the base, supported by a 

 longer pedicel and a comparatively more slender rod (PI. XLII. fig. 1). 



Amboyna, 100 fathoms. 



Amboyna, 15 to 25 fathoms. 



Dorocidaris (Cidaris) papiUata. 



Cidaris papillata, Leske, 1778, KL Add. 



Dorocidaris jMpillata, A. Agassiz, 1869, Bull. Mus. Couip. ZooL, vol. i. 



The collections of the Challenger show that this sjDecies has an extensive geographical 

 range both in the Atlantic and Pacific. Its distribution in the Western and Southern 

 Atlantic corresponds with that of Cidaris trihidoides ; the latter has, however, as yet not 

 been found in the Eastern Atlantic north of the Cape Verde Islands, while, as is well 

 known, Dorocidaris pajnUata is found also far north in the North-Eastern Atlantic. The 

 specimens collected in the Philippine Islands cannot be distinguished from those of the 

 Atlantic. The deep water forms generally resemble the variety I had described as 

 Dorocidaris ahyssicola. The whole question of the specific characters of Dorocidaris 

 papillata having been reopened by the discovery of Dorocidaris blakii, this identi- 

 fication of the Pacific and Atlantic specimens is of course subject to considerable doubt. 



St Paul's Rocks. 70 to 80 fathoms. 



Station 24. March 25, 1873. Off Culebra Island; 390 fathoms; mud. 



Gomera, Canary Islands ; 70 fathoms. 



Station 320. February 14, 1876. Lat. 37° 17' S., long. 53° 52' W. ; 600 fathoms; 

 bottom temperature, 27° C. ; hard ground. 



Station 210. January 25, 1875. Lat. 9° 26' N., long. 123° 45' E. ; 375 fathoms; 

 bottom temperature, 12'2° C. ; mud. 



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

 and 115 fathoms; mud. 



