120 HAWAIIAN AND OTHER PACIFIC ECHIXI. 



are wholly wanting, and are most numerous in the Californian coronahis, 

 which at first glance most resembles asteriscus. The colors are much the 

 brio-htest in asteriscus. The radicles of the largest specimen of asteriscus 

 (14 mm.) are about one-half longer than the diameter of the test. This 

 specimen is 6.25 mm. high, the abactinal system is 5.5 mm. in diameter, and 

 the actinal, 6 mm. The radioles are marked by widely spaced whorls of 

 very minute sharp spinelets (PI. 55, figs. 5, 6). 



The primary interambulacral tubercles form two rows flanked by a row 

 of indistinct secondaries adjoining the poriferous zone and an irregular double 

 median row along the vertical suture. The secondaries are most prominent 

 about the equatorial zone or ambitus (Pis. 55, figs. 1-3 ; 58, figs. J^-6). 



The primary ambulacral tubercles are much smaller and form two single 

 vertical rows separated on the median line by a few irregularly placed sec- 

 ondaries. At the actinal edge of the ambulacral zone the pairs of pores of 

 the first three plates are more or less crowded together but have their regu- 

 lar arrangement somewhat higher up (PL 55, fig. J^). The actinal mem- 

 brane is covered with five or six rows of narrow elongate plates outside of 

 the five pairs of buccal plates, which are large, forming a connected ring. 

 Between the buccal plates and the teeth there are two or three irregular 

 rows of small rounded plates. The color of the test is light reddish, be- 

 coming reddish-white actinally, and the primary radioles are banded with red 

 and whitish ; from the end of each ambulacrum a conspicuous white line 

 runs straight to the centre of the anal system, the five lines forming a con- 

 spicuous star on the red abactinal surface. This star is well marked in alco- 

 holic specimens, but becomes very faint when they are dried. 



The pedicellariae are abundant, diverse, and very characteristic. The 

 globiferous (PI. 51, fig. 8) are the most striking because of the conspicuous, 

 dark-colored glands which enclose or at least conceal the terminal half of the 

 valves. These pedicellariae are quite common and occur all over the test 

 and on the actinostome. The heads are about .35-. 45 in lentj:th and are 

 borne on stalks two or three times as long. Glands are commonly present at 

 the upper end of the stalk, but are never very conspicuous. The valves 

 (PI. 51, figs. .9, 10) arc .30-. 40 mm. long and terminate in 5 or 6 long and 

 conspicuous teeth. The blade is nearly cylindrical, except at tlie expanded 

 tip, and is scarcely at all hollowed, though fiattened on its inner surface. The 

 basal part is not so long as the blade, but the apophysis is very high and 

 conspicuous. 



