. Echinoidea. Sea urchins. ECHINOIDEA. II. 151 cellariæ were hitherto very insufficiently known; a few figures are given iu Revision of Kchini â PL XXV. 29â30 and PI. XXVI. 19, and Koehler (Op. cit. PI. 4. 14) gives a fignre of one kind of pedi- cellariæ. I have found globiferous, rostrate, tridentate and triphyllous pedicellariæ, bnt no opliicephalons. The globiferons pedicellariæ (PI. XVII. Figs. 12, 47) are rather like those of cordatum, only the blade is generally more elongate (thongh not always so elon- gate as in the fignred valve), and the basal part is nar- rower. 3â4 teeth are fo
. Echinoidea. Sea urchins. ECHINOIDEA. II. 151 cellariæ were hitherto very insufficiently known; a few figures are given iu Revision of Kchini â PL XXV. 29â30 and PI. XXVI. 19, and Koehler (Op. cit. PI. 4. 14) gives a fignre of one kind of pedi- cellariæ. I have found globiferous, rostrate, tridentate and triphyllous pedicellariæ, bnt no opliicephalons. The globiferons pedicellariæ (PI. XVII. Figs. 12, 47) are rather like those of cordatum, only the blade is generally more elongate (thongh not always so elon- gate as in the fignred valve), and the basal part is nar- rower. 3â4 teeth are foiind on either side of the term- inal opening, and there may be one in the middle of the onter edge; the terminal opening may sometimes be qnite covered by the teeth. i^s is nsual 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 withont free projecting rods. -- The Fig. 19. PI. XXVI of Revision of Echini , in the explanation of piates termed an open- headed actinal« pedicellaria, evidently represents the val\'e of a globiferons pedicellaria. â The rostrate pedi- cellariæ are rather large and very characteristic (PI. X\'II. Figs. 3, 52); the valves are coarsely dentate along the side , the point, which is more or less ronnded, finely serrate. They reach a rather considerable size, ca. I â i-2'""i length of head. The Fig. 29, PI. XXV of i. Rev. of Ech. ( long-headed â pedicellaria), as well as the PI. 4. Fig. 14 (pedicellaire gemmiforme) of Koehler (Op. cit.) evidently represent this form. Anything nearly resembling the PI. XXV. Fig. 30 of Rev. of Ech. I have not seen. The tridentate pedicellariæ occnr in two, not very sharply distingnishable forms; the one (PI. XVII. Fig. 2) has slender, leafshaped valves, the larger ones joining only in the onter half; the lower part is more or less coarsely serrate, the basal part rather narro
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