De sekundære Tuberkler, saavel paa Ambulacral- som 

 Interambulacralpladerne, ere i det Hele større og ordne 

 sig mere i Rækker under Periferien, end over denne. 



Ambulacralporerne ere i Regelen stillede i 3 lidt 

 paaskraa gaaende Rækker, kun undtag eises vis er der 4, 

 Tab. I, Fig. oe; men oftere sees et Par imellom to Tre- 

 rækker. Tab. I, Fig. of. 



De primære Pigge ere paa Interambulacralpladerne 

 længst. opnaa indtil 45 mm i Længde, have en temmelig bred 

 Basaldel og ere efter Længden forsynede med omtrent 25 

 Længdefurer og ligesaa mange Længderibber, der nede ved 

 Basaldelen udvider sig noget, hvorved det faar et Udseende, 

 som om der rundt Basalens øverste Rand er en Krands af 

 25, eller ligesaa mange smaa. runde Knuder, som der gives 

 Ribber paa Piggen, Tab. T, Fig. 4a; en Anordning, som 

 forresten er temmelig almindelig ved Ecbinidernes Pigge. 



Analfeltet (abactinal System) er vidt, den membranøse 

 Del (Periprocte) er tæt besat med runde Kalkkar. der have 

 omtrent samme Størrelse i Periferien som Centrum, kun 

 staa de længere fra hverandre omkring Analaabningen, hvor 

 de ere lidt større, Tab. I, Fig. 5a. 



Den egentlige Analring dannes af 5 Genitalplader ; 

 disse ere septagonale, 9""" brede, 6""" høie, have en stor 

 aflang Pore paa Midten. Tab. I, Fig. 3 g, 5 lx Opimod 

 enhver Plades øverste Rand er der 3 Tuberkler, Tab. I, 

 Fig. 3 h, 5 e, og hvor 2 Plader stode sammen, er henimod 

 Sideranden 1 lignende Tuberkel, Tab. I, Fig. 3 i. Alle 

 disse Tuberkler, 20 i Antal. bære en Pig, der hjælper til 

 at danne den Pigring. som omgiver det membranøse Anal- 

 felt, Tab. I, Fig. 1. Imellein de nysnævnte Randtuberkler 

 sees enkelte, spredte Miliartuberkler, forresten ere Genital- 

 pladerne ganske glatte. Paa den ene af Genitalpladernes 

 øverste Del, imellem de omtalte 3 Tuberkler og Genitalporen, 

 iagttages Madreporpladen, der har en kornet, temmelig 

 opiiøiet, hvælvet og aflang Overflade, er 5"" bred og 2""" 

 hoi. Tab. I, Fig. 5 d. Ocularpladerne ere 4'""' høie og 4""" 

 luede, have 7 Hjørner, hvoraf det øverste er indkilet imel- 

 lem 2 Genitalpladers skjære, ydre Rande; paa det nederste 

 Hjørne er den runde Pore, og paa den ydre Flades overste 

 Del er en Del Miliartuberkler, Tab. I, Fig. 5 e. 



Skallet er særdeles rigt besat med treklappede Pedi- 

 cellarier, men rigest er dog Underfladen, ligesom Interam- 

 bulacralfeltet er tættere besat end Ambulacralfeltet. De 

 ere uregelmæssigt stillede og kunne henføres til 3 Former. 

 der alle ere afbildede. og til hvilke Figurer henvises, Tab. 

 I. Fig. 6, 7, 8, 9. 



Farven. Grundfarven er smuk kjodrød. Analfeltet 

 mørkt kastaniebrunt, hvorfra udgaa lysere kastaniebrune, 

 brede Rande langs Ambulacrerne og de primære Pigge til 

 den mørke, kastaniebrune Mundmembran. Ambulacrerne 

 violette med kastaniebrun Ring om den yderste Ende, samt 

 en næsten hvid Sugeskive. De primære Pigge jævnt kastan- 



The secondary tubercles, both on the ambulacral and 

 interambulacral plates, are altogether larger and arranged 

 more in series under the periphery than above it. 



The ambulacral pores are usually placed in 3, some- 

 what obliquely running series, only occasionally are there 

 4 series (Pl. I, fig. 3 e), but frequently a pair are seen 

 between two triple oblique series (Pl. I. fig. 3 f). 



The primary spines are longest on the interambul- 

 acral plates, reaching up to 45""" in length, have a pretty 

 broad basal portion, and are furnished longitudinally with 

 about 25 longitudinal groves and a similar number of longi- 

 tudinal ribs, which become somewhat expanded down in 

 the basal part, causing an appearance as if there were. round 

 the uppermost margin of the basal part. a wreath of 25. or 

 same number of small, round no d ules as there are ribs 

 on the spine (Pl. I, fig. 4 a); an arrangement which is 

 otherwise pretty common in the spines of Echinidæ. 



The anal area (abactinal system) is wide; tlie mera- 

 branous portion (periprocte) is closely covered with round 

 calcareous vessels, which have about the same size in 

 the periphery as in the centre, but stand farther apart from 

 each other round the anal aperture, where, also, they are 

 a little larger (Pl. I, fig. 5 a ). 



The real anal ring is formod of 5 genital plates; 

 these are septagonal, 9""" broad. P) mro high, and have a large 

 oblong pore in the middle (Pl. I, figs. 3 g, 5b). Towards 

 the uppermost margin of each plate there are 3 tubercles 

 (Pl. I, figs. 3 h, 5 c). and where 2 plates unite there 

 is. near the lateral margin. 1 similar tubercle (Pl. I, 

 fig. 3 i). All those tubercles, 20 in number. carry a 

 spine, which aids in forming the spinal ring that surrounds 

 the membranous anal area (Pl. I. fig. 1). Between the 

 marginal tubercles just mentioned, a few scattered miliary 

 tubercles are visible; the genital plates are otherwise quite 

 smootb. On the uppermost part of one of the genital plates, 

 between the 3 tubercles spoken of and the genital pore, 

 the madrepore-plate is observed. It has a granular, pretty 

 elevated, arcuate and oblong surface, is b mm in breadth and 

 2""" in height (Pl. I. fig. 5 d). The ocular plates are i""" 

 high and 4 mm broad, have 7 corners, the uppermost one of 

 which is wedged in between the distorted outer margins of 2 

 genital plates; the round pore is on the lowest corner, and 

 on the uppermost part of the outer surface a number of 

 miliary tubercles are visible (Pl. I, fig. 5 e). 



The shell is particularly richly covered with trilobate 

 pedicellaria, but the inferior surface is, yet, the most richly 

 covered, while, also, the interambulacral area is more densely 

 covered than the ambulacral area. They are irregularly 

 placed and may be assigned to 3 forms, all of which are 

 illustrated, and to the figures of which the reader is refer- 

 red (Pl. I, figs. 6. 7, 8, 9). 



The Colour. The ground-colour is a beautiful car- 

 mine red. The anal area is dark, chestnut brown, from 

 which issue lighter, chestnut-brown, broad margins along the 

 ambulacra and the primary spines to the dark, chestnut- 

 brown oral inembrane. The ambulacra are violet, with 

 chestnut-brown ring on the outermost extremity, and an 



