ECHNIOIDEA. II. z ^ 



Ech. p. 12. — Diiben & Koren: Skandinaviens Echinod. p. 283. Tab. X. 50. — M. Sars: Beskrivelser 

 og Iagttagelser. 1S35. p. 46. PL IX. 23. Norges Echinod. p. 98. — Gray: Catal. Rec. Eehinida. p. 43. - 



Perrier: Rech. sur les pedicellaires. p. 175. PL VII. 2. a.— f. — Th. Barrois: Echinod Acores (30). 



p. 12. Catal. Ech. Concarneau (29). p. 46. — Bolau: Spat. Hamburger Mus. (82). p. 10. — A. Agassiz: 

 Revision of Echini, p. no, 351. PL XX. 3— 4. XXV. 26. — Loven: Etudes sur les Ech. PI. III. 33— 37. 

 On Pourtalesia. PL XI. 127-30. PL XV, XVII. — Ludwig: Echinodermen d. Mittelm. p. 561. — Bell: 

 Catalogue Brit. Echinoderms. p. 171. PL XVI. 6—7. — Hoyle: Revised List Brit. Echinoidea. p. 428. 



— Koehler: Recherches s. les Echinides de Provence, p. 129. PL VII. 57, 59— 60. Sur les Echinocar- 

 dium de la Mediterranee (231). p. 180. PL IV. 5— 13. — Grieg: Overs, uordlige Norges Echinod. p. 34. — 

 Doderlein: Arktische Seeigel. Fauna Arctica. p. 384. Echinoideu d. deutschen Tiefsee-Exped. p. 268. 



Non.: A. Agassiz: Challenger--Echinoidea. p. 175. — Bell: Echinoidea. South Africa, p. 174. 



— Gas co : Descrizioue Ech. nuovi (159). p. 6. Fig. 3. 



For other literary references see: «Revision of Echini*, Bell: Catalogue Brit. Ech., Ludwig: 

 Echinod. d. Mittelmeeres, and Koehler: Sur les Echinocardium de la Mediterranee. 



This species has been so very often described and figured that little new can be added, espe- 

 cially after the elaborate comparative study of the European species of the genus Echinocardium given 

 by Koehler. Some few remarks, however, may be made, and especially the pedicellarise of this and 

 the other species need a closer examination than has hitherto been made of them. 



Eminently characteristic of this species are, as pointed out by Koehler, the large tubercles 

 outside the fasciole, along the anterior ambulacrum and in the lateral interambulacra. Koehler finds 

 these tubercles more numerous in the small than in the larger specimens. This is not in accordance 

 with my observations. In a small specimen of 8-5 mm length I find only a few larger tubercles in the 

 anterior interambulacra; in a specimen of io mm length there is also a single large tubercle in the 

 posterior interambulacrum. A specimen of ic; mm length has, besides several large tubercles in the ante- 

 rior and in the odd posterior interambulacrum, a single large tubercle in the left lateral interambula- 

 crum, just behind the left anterior petal. Later on more large tubercles appear, especially along the 

 posterior edge of the anterior petals, large specimens having here generally several close-set large 

 tubercles, besides more or fewer spread on the upper plates of these Interambulacra. I have seen no 

 specimens agreeing with that figured in PL 4. Fig. 10 by Koehler (Echinocard. de la Mediterranee), 

 and the suggestion that this figure represents, really, another species, seems not quite unfounded. 

 (Comp. below, p. 143 — 4.) 



The labrum reaches the anterior end of the second adjoining ambulacral plates; sometimes it 

 reaches to the middle of these plates, but generally their anterior, inner corner is produced to meet 

 the labrum. In young specimens (comp. PL XV. Fig. 172 in Loven's «On Pourtalesia*) it does 

 not reach beyond the first ambulacral plate; in a specimen of 8 - 5 mm I find it still reaching only to 

 the end of the first ambulacral plate. — The anterior edge of the labrum is straighter than in 

 the other species, (except pennatiftdum) as pointed out by Agassiz (<Rev. of Ech. p. 351). — The 

 number of pores included by the subanal fasciole is, as stated by Bell, one or two pairs, both cases 

 occurring almost equally frequently. In one case I have found the first ambulacral plate reaching 



