CLARK: THE CIDARIDAE. 209 



.60 li. d. in vertical diameter, and it, as well as the secondaries, is pale brown or 

 yellowish; the abactiual system is sometimes quite red; the uppermost coronal 

 plates do not carry primaries, and even the second ones may lack a well-developed 

 spine; the primaries are usually about 1.25 h. d. and never exceed 2 h. d. The 

 diameter of the test is usually about 25 or 30 mm. but is sometimes 35 or 40, and 

 the largest specimen is 68 mm. h. d. This species ranges from St. Lucia north- 

 ward to the coast of South Carolina and the region south of Martha's Vineyard 

 at depths of 100-200 fths. 



Dorocidaris papillata. 



Cidaris papillata Leske, 1778, Add. Nat. Dis. Ech. Klein, p. 61 (partim). 

 Dorocidaris vapillata A. Agassiz, 1869, Bull. M. C. Z., 1, p. 264. 



late lb, Rev. Ech., A. Agassiz, 1873. 



Nothing more need be said of this well-known species than that it does not 

 seem to occur in the western part of the Atlantic, but is apparently confined to the 

 northern and eastern parts of that ocean and to the Mediterranean Sea. The 

 bathymetric range is from a few fathoms down to about one thousand. Mor- 

 tensen's (:03, p. 170) assurance that the " Challenger" specimen from St. Paul's 

 Rock is really papillata is important in this connection, but I think it possible that 

 the individual may prove to be rugosa! In size papillata reaches a diameter of 

 58 mm., while in color it is quite variable, ranging from grayish-white to reddish- 

 yellow, becoming brick-red on the abactiual system, with dull grayish or yellowish 

 primaries. 



Dorocidaris nuda. 

 Dorocidaris nuda Mortensen, 1903, Ingolf-Exp. Ech., p. 171. 



This species is apparently distinct from all the other members of the genus, but 

 its real relationships can only be determined when it is more fully described. 

 Possibly it is not so closely allied to papillata as I have assumed. The size is not 

 mentioned, but the test is white and the spiues purple or reddish-brown. It has 

 been taken only in the Gulf of Guinea and near the Cape Verde Islands, in 53- 

 250 fths. 



Dorocidaris blakei. 



Dorocidaris Blakei A. Agassiz, 1878, Ball. M. C. Z., 5, p. 185. 



Plate 4, Bull. M. C. Z., 5, 9, A. Agassiz, 1878. Plate 1, Blake Ech., A. Agassiz, 



1883. 



This is one of the most interesting discoveries of the " Blake," and specimens 

 with fully developed primaries are indeed unique. The color is grayish with more 

 or less of a yellow-brown tinge to the test. The largest specimen is 37 mm. h. d. 

 with spines 76 mm. long. Specimens in which there are none of the conspicu- 

 ously flattened primaries are easily recognized by the large abactiual system, 



VOL. LI. NO. 7 14 



