. Carnegie Institution of Washington publication. IL W M. 15 16 17 Figs. 15-17.âAberrant ocular plate arrangement in Tripneustes esculentus (Leske). Montego Bay, Jamaica. All figures nearly X 2. Fig. is.âDiameter lis mm. Oculars I, IV, II insert, a common aberrant variant, a right-lianded equiva- lent of the normal character I. V, IV insert. ..,.â .. ^i, 1 i,->â Fig. 16.âDiameter 106 mm. Oculars I. V, IV. Ill msert, a rare aberrant variant, but the usual one when four oculars but not I, V, IV, II are insert. _ . ., t. j j Fig 17 âDiameter 102 mm. Oculars I, V, II, III insert, a unique aberr
. Carnegie Institution of Washington publication. IL W M. 15 16 17 Figs. 15-17.âAberrant ocular plate arrangement in Tripneustes esculentus (Leske). Montego Bay, Jamaica. All figures nearly X 2. Fig. is.âDiameter lis mm. Oculars I, IV, II insert, a common aberrant variant, a right-lianded equiva- lent of the normal character I. V, IV insert. ..,.â .. ^i, 1 i,->â Fig. 16.âDiameter 106 mm. Oculars I. V, IV. Ill msert, a rare aberrant variant, but the usual one when four oculars but not I, V, IV, II are insert. _ . ., t. j j Fig 17 âDiameter 102 mm. Oculars I, V, II, III insert, a unique aberrant variant, a right-handed equiva- "lentof I. V. IV, Illinsert. Tripneustes has oculars I, V, II, III insert (fig. 17). This, which is a right-handed equivalent of I, V, IV, III (just as I, V, II is a right-handed equivalent of I, V, IV) is a unique variant for Echini as far as my experi- ence goes. In the Centrechinoida, as tabulated in my preceding memoir and in the present paper, 619 specimens are recorded, in which four plates reach the periproct. Of these, in 554 specimens ( per cent) it is oculars I, V, IV, II the bivium and posterior pair of the trivium, in 64 specimens ( per cent) it is the aberrant arrangement I, V, IV, III, and in the one specimen cited ( per cent) it is I, V, II, III. (Compare figs. 13, 16, 17.) The series containing the largest specimens, no to 132 mm. diameter, 82 specimens, has 13 per cent with oculars I, V insert as arrested variants (fig. 11); 24 per cent with I, V, IV insert as arrested variants (fig. 12); and 43 per cent with I, V, IV, II insert as the local character of the species (fig. 13). Five per cent have all oculars insert as a progressive variation, and 15 per cent, 12 specimens, are aberrant in ocular arrangement. Of these. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfect
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Keywords: ., bookauthorcarnegie, bookcentury1900, bookdecade1910, bookyear1914
