300 Verrill, ISFotes on Radlata. 



Echinocidaris spatuligera Agassiz, Catai. Rais., 1846* 



Echinus spatuUijer Val., Voyage Venus, Zool, pi. 5, fig. 2, 1846. 



Numerous specimens of this species were found by Mr, Bradley 

 both at CaUao and Paita, Peru, thrown upon the shore after storms. 

 It has been recorded from Coquimbo (Catal. Rais.), and from North 

 Chili (Philippi). 



A specimen of the usual size has a diameter of 2*1, not including 

 spines; height 1*3 ; longest spines 1*8 ; diameter of actinal area "98; 

 of anal area "28 ; from the outside of an ocular plate to the outer end 

 of the opposite genital plate "48 ; length of genital plates 'IS ; width 

 •15. Test with a regularly rounded outline, often subconical, some- 

 times regularly arched above, usually less depressed than the preced- 

 ing species. 



The genital plates are rather small, with an obtuse angle outwardly, 

 the adjacent ones usually separated completely by the ocular plates, 

 which reach the anal area, except the two next to the madreporic 

 plate. The ambulacral zones have two close rows of tubercles, which 

 become very small on the U2:)per surface and do not reach the summit. 

 The interambulacral plates are narrower and more numerous than in 

 the preceding species, 1 8 forming a vertical series : those near the outer 

 parts and beneath, except near the actinal opening, bear four tubercles, 

 forming obliquely transverse rows on the plates and eight vertical rows 

 in each interambulacral zone, of which the two middle rows are irreg- 

 ular and consist of smaller tubercles. The primary tubercles, below 

 and on the sides, are croAvded, subequal, of moderate size. The row 

 next the ambulacra reaches the ocular plates, the upper tubercles, like 

 those of all the other rows, being very small ; the next row ceases at 

 the fourth plate fi-om the summit ; the third, two plates sooner; the 

 fourth, two or three plates sooner than the third. The median naked 

 spaces of the upper side are, therefore, narrow and less distinctly 

 bounded than in JE. stellata, owing to the smallness of the surrounding 

 tubei'cles. 



The color of dried specimens is dark reddish brown, much lighter 

 beneath ; spines reddish or purplish brown. Young specimens have 

 purplish poriferous zones, and grayish brown interambulacral spaces. 



A specunen "9 of an inch in diameter has five rows of interambu- 

 lacral tubercles with rudiments of a sixth. The outer rows reach the 

 summit, but the next cease at the sixth plate from it. 



A young specimen, '5 in diameter, has but four rows of interambu- 

 lacral tubercles, the two outer rows reaching the smnmit, the others 

 scarcely extending above the outer curvature of the sides. 



* A recent examination of this species confirms its identity with that of Valenciennes, 



but the latter differs in its flatter spines, which in ours is variable, — Reprint. 



