ECHINOIDEA. II. 



151 



cellariEe were hitherto very insufficiently known; a few fio^nres are given in Revision of Kchini» 

 PLXXV.29-30 and PI. XXVI. 19, and Koehler (Op. cit. PI. 4. 14) gives a figure of one kind of pedi- 

 cellarise. I have found globiferous, rostrate, tridentate and triphvllous pedicellarifE, but no ophicephalous. 

 The globiferous pedicellarise (PI. XVII. Figs. 12, 47) are rather like those of cordahim, only the blade 

 is generally more elongate (though not always so elon- 

 gate as in the figured valve), and the basal part is nar- 

 rower. 3—4 teeth are found on either side of the term- 

 inal opening, and there ma}- be one in the middle of 

 the outer edge; the terminal opening may sometimes 

 be quite covered by the teeth. As is usual the valves 

 are covered by a thick .skin (PI. XVII. Fig. 47); the stalk 

 is rather thick and compact, knotted, with a distinct 

 thickening above and below, the latter without free 

 projecting rods. - The Fig. 19. PI. XXVI of Revision 

 of Echini , in the explanation of plates termed an open- 

 headed actinal» pedicellaria , evidently represents the 

 \al\-e of a globiferous pedicellaria. — The rostrate pedi- 

 cellarise are rather large and very characteristic (PI. XVII. 

 Figs. 3, 52); the valves are coarsely dentate along the 

 side edges, the point, which is more or less rounded, 

 finely serrate. They reach a rather considerable size, Fig. 25. Apical area of Echiiwcardhim mediterraneum 

 ca. I — r2'""' length of head. The Fig. 29, PL XXV of ■*''■ 



«Rev. of Ech.) («long-headed pedicellaria), as well as the PI. 4. Fig. 14 (pedicellaire gemmiforme) of 

 Koehler (Op. cit.) evidenth- represent this form. Anything nearly resembling the PI. XXV. P~ig. 30 of 

 - Rev. of Ech. • I have not seen. 



The tridentate pedicellai'ife occur in two, not very sharply distinguishable forms; the one 

 (PI. XVII. Fig. 2) has slender, leafshaped valves, the larger ones joining only in the outer half; the 

 lower part is more or less coarsely serrate, the basal part rather narrow. The other form (PI. XVII. 

 Fig. 19) has short valves, generally a little inrolled in the lower part, and sometimes ending in a dis- 

 tinct tooth. This form to some extent recalls the form, which I have termed rostrate pedicellaria in 

 Ecli. flavescens — and it is, indeed, rather difficult to determine with certainty to which kind it ought 

 really to be reckoned, the rostrate pedicellariae being, as repeatedly pointed out, essentialh- a special 

 form of tridentate pedicellariae. — The triphyllous pedicellarice (PI. XVI. Fig. 16) are rather like those 

 of cordatmn, with similar teeth inside along the edge of the blade. — Spicules seem to be almost 

 wholly wanting in the tubefeet, and no large spicules are found below the disk of the frontal tubefeet 

 which are otherwise well developed and like those of cordatum. 



After the revision of the species of Echiuocardium given here it will perhaj)s not be found 

 useless to give an anahtical table of all the species hitherto recognized with certainty. 



