30 HAWAIIAN AXD OTHER rACIFIC ECHINI. 



Anomocidaris A. Ag. ami Clark. 



Tliiis genus is established for a specimen we take to be Cidari.'^ /emnsjniia 

 Yosliiwara' (PI. ol, figs. J-,v). It can at once be distinguislied from all 

 other Cidaridte by the sliarp, deep sutures separating the plates of the abac- 

 tinal system, and of the interambulacral areas, and the deep median vertical 

 suture of the ambulacral area. Towards the actinal system the sutures tend 

 to imitate, at the angles of both the ambulacral and interambulacral plates, 

 those of some species of Goniocidaris. When seen from above the general 

 aspect of the test resembles somewhat that of the ArbaciadiB, the upper inter- 

 ambulacral plates having no well developed primary tubercles, much as in 

 Coelopleurus, and among the CidaridEe in Diplocidaris and to a lesser degree, 

 in some species of Stereocidaris. The primary tubercles begin onlv at the 

 equatorial zone and extend from there to the actinal system. The primary 

 radioles (Plate 12, fig. Ifi) resemble a combination of those of Dorocidaris and 

 of Porocidaris. Anomocidaris is notable for its conical test and the presence 

 of rudimentary abactiual primary tubercles. 



Anomocidaris tenuispina A. Ag. ami Clark. 



Cidaris (Stereocidaris) tenuispina Yosliiwara, 1S'.)8. Aiinot. Zool. Jap., II, p. .'')7. 

 Plates 11, figs. 6-12; 12, figs. J 8-30 ; 31, figs. o-S. 



The only specimen of this species collected measures 29 mm. in diameter; 

 the abactinal system is circular, 14 mm. in diameter, the actinal system is 

 pentagonal and 10 nun. across. 



The genital plates are large, irregularly heptagonal. The anal system 

 is sharply pentagouid, included by the genital plates. The genital pores are 

 large ; the ocular plates are small, elongated triangular, deeply cut into by 

 the ambulacral system ; the ocular pores are prominent; the whole abactinal 

 system is covered with irregularly arranged, distant, small secondaries and 

 interspersed miliaries. A similar granulation extends over the interam- 

 bulacral j^lf^tes above the equatorial belt and surrounds an ill-defined 

 scrobicular area with a rudimentary low, imperforate tubercle. Jkdow 

 the equatorial belt, there are five or six ])rimary tubercles, usually two 

 large ones at the ambitus, gradually diniiuishing in size. Tlie scrobicular 

 areas are well defined, somewhat sunken, edged by a large ring of 



1 Amiot. Znul. .lap. ls:iS, \'.il. II, p. .')". 



