ECHNIOIDEA. II. 7g 



in the anihulacial plate V. b. i, hut not in I. a. i. I may call attention to the fact that the abactinal plates 

 of the odd interambnlacrnm arc alternating;, not ])aire(l as in /'. /.''//Wy.sv'. as correctly fijjnred b\- Ag^as- 

 siz and Loveii. The pedicellarise are upon the wluile well figured in the Challenger -Report, though 

 no mention is made of them in the text. The forms fissured there are globiferous, ophicephalons and 

 tridentate. The globiferous pedicellariije (figured in PI. XL\". Fig. 56 as a broad based, slender-pronged, 

 and hooked pedicellaria >) agree rather closely with those of /-". cariiialu. The ophicephalons pedicel- 

 larite (figured in PI. Xlyll. Fig. 18, XLIH. Fig. 16 and XLV. Figs. 53— 54 as Clypeastroid-like pedi- 

 cellarite) differ from those of P. Jeffrrysi in having more numerous teeth along the edge of the ter- 

 minal widening, and these teeth continue along the . dorsal side of tlie widening, whereas in Jeffreysi 

 the\- are onh' found along the inner side. This feature is well shown (jn PI. XLV. 53. — The pedi- 

 cellaria figured in PI. XLIII. 17 is said to be a small Cl>peastroid-like (ophicephalons) pedicellaria. 

 This nnist, evidenth', be a mistake; the long neck shows that it is no ophicephalons ])edicellaria, this 

 form of pedicellaria; being always devoid of a neck in the Irregular Echini. Probal)ly it is a small 

 tridentate pedicellaria like that figured in PL XLII. 20, only with the valves opened. The tridentate 

 pedicellaricc occur in two forms; probably there will be found intermediate forms as in airiiiata. but 

 I have not found such. The smaller form has simply leafshaped, more or less elongate valves, with 

 the apophysis continuing into the edges, (figured in PL XLII. ig — 20, XLIII. 15 and XLV. 59 as large- 

 headed pedicellarise); the end-tooth is only little prominent in the larger ones. The larger form 

 (PL XLII. 17, XLV. 57 — 58) has very slender, narrow valves, ending in a rather short hook and with 

 the edges serrate onh- near the point; this is a rather large form, the head reaching a length of ca. 07'"™. 

 Regarding PoiirtaUsia rosea A. Ag. it is stated in the Challenger»-Echinoidea (p. 140) that the 

 tuberculation of this species, and the shape of the test, must have been very similar to that of Poitr- 

 talesia ceratopyga . In the British Museinn are preserved only the anal snout represented in PL XXII. a. 

 Fig.s. 3 — 5 and some ver\' poor fragments connected with a genital organ; from these fragments alone 

 it is certainly impossible to judge of the shape of the test — it seems even not very likely that they 

 belong to one species. The figures given in the Challenger) Ech. do not give a better proof of the 

 .shape of the test; the apical area figured in PL XXII. a. Fig. 6 with the large tliin plates, .showing 

 distinct concentric striation, recalls much more the thin plated Cysfcchi/ius clypcaliis than a species of 

 Poiirtalcsia . and it still more resembles the apical system of Sfcrnofatagus as pointed out b\- de 

 Meijere (Op. cit. p. 163). (I have been unable to detect the apical system among the fragments pre- 

 served in the British Museum). I want to maintain that there is no proof in the description and figures 

 given in the Challenger -Echinoidea, and neither is such proof afforded by the fragments preserved 

 in the British RIu.seum, that the apical system figured PL XXII. a Fig. 6 really belongs to the .same 

 species as that to which the anal snout figured in the same plate Figs. 3 — 5 belongs, and I for ni\- 

 part think it probable that this apical system does not belong to any Pourtdhsiu at all, no other 

 species of this genus having a compact apical s\stem. To be sure, Duncan states in his « Revision- 

 (p. 282) that the apical system of P. iiiiraiida is compact like that of P. rosea, as can most distinctly) 

 be seen on the PL XVIII. Fig. 9 of the Revision of Echini . This figure, however, only shows four 

 genital openings close together — it does not show an\-thing of plates, especially of the jiosterior 

 ocular plates. L'ntil P. niinuidtJ has been rediscovered and carefully examined we nia\ think it probable 



