Archive image from page 363 of The Danish Ingolf-expedition (1899-1953). The Danish Ingolf-expedition danishingolfex4apt1a2daniuoft Year: 1899-1953 6o ECHINOIDEA. II. have coustantlv foimd both the inner plates of I and V developed; but the plates I. b. i and \'. a. i are o-enerally verv small and easily overlooked. The plates I. a. i and \'. b. i nia\- be \ery nnequalh- developed, one of them simulating the labrnm, but the presence of the pore at its inner end shows its real nature. Generally onl\- the four larger of these plates bear distinct pores and tube-feet, in the other plates onlv q
Archive image from page 363 of The Danish Ingolf-expedition (1899-1953). The Danish Ingolf-expedition danishingolfex4apt1a2daniuoft Year: 1899-1953 6o ECHINOIDEA. II. have coustantlv foimd both the inner plates of I and V developed; but the plates I. b. i and \'. a. i are o-enerally verv small and easily overlooked. The plates I. a. i and \'. b. i nia\- be \ery nnequalh- developed, one of them simulating the labrnm, but the presence of the pore at its inner end shows its real nature. Generally onl\- the four larger of these plates bear distinct pores and tube-feet, in the other plates onlv quite rudimentary pores are present, sometimes the pore has even quite disappeared. Besides the supposed coalescence between the two inner plates of ambulacra I and V, Loven, points out (Op. cit. p. 36) as another peculiar feature in this species, that the inner plates of ambulacra II and IV are not in accordance with the general rule that the plates I. a, II. a. III. b, I\'. a, \'. b are the largest. I have constantly found the inner plates of the paired ambulacra to be in accordance with the rule, only as to ambulacrum lY I have sometimes been unable to see it distiucth-. As it seems very unlikely that all the specimens examined by Loven should happen to be abnormal in tliis respect, I must \enture to suggest that Loven has overlooked some of these small plates, which may, indeed, be rather difficult to see. 11 have found them easiest to discern when examining the denuded test in alcohol; on dried tests, treated with alcohol-glycerine it is almost impossible to trace the limits between the small plates). A very small plate may sometimes be found be- tween the inner plates of the ambulacra I and II on one side and IV and \' on the other side (PL \'III. Figs. 5, 8, 9, 11). It must doubtless be regarded as the rudimentary inner plate of the interambulacra i and 4. Whether this plate was really absent in Loven's specimens or perhaps was overlooked, it follows from its occasional (
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Keywords: 1890, 1899-1953, archive, arctic_regions, book, bookauthor, bookdecade, bookpublisher, booksubject, bookyear, copenhagen_h_hagerup, danish_ingolf_expedition_1895_1896_, drawing, historical, history, illustration, image, k_benhavns_universitet_zoologisk_museum, marine_animals_arctic_regions, page, picture, print, reference, scientific_expeditions, vintage
