. Discovery reports. Discovery (Ship); Scientific expeditions; Ocean; Antarctica; Falkland Islands. OPHIOCHITONIDAE 299 to practise self-division, three of the specimens in hand having the three arms in re- generation. This is not known to be the case in any other species of Ophionereis, as, indeed, self-division does not normally occur in five-armed Ophiurids. The fact that only three specimens out of nine show any trace of self-division indicates that this method of propagation is not constant, but evidently occurs only in a certain percentage of the specimens; still it is common enough to b
. Discovery reports. Discovery (Ship); Scientific expeditions; Ocean; Antarctica; Falkland Islands. OPHIOCHITONIDAE 299 to practise self-division, three of the specimens in hand having the three arms in re- generation. This is not known to be the case in any other species of Ophionereis, as, indeed, self-division does not normally occur in five-armed Ophiurids. The fact that only three specimens out of nine show any trace of self-division indicates that this method of propagation is not constant, but evidently occurs only in a certain percentage of the specimens; still it is common enough to be regarded as a normal feature of the species. In his memoir on the Echinoderms in Michaelsen's Meeresfauna Westafrikas Koehler does not record any species of Ophionereis from the African coast. Evidently he overlooked that Marktanner-Turneretscher {Beschreibiingen neiier Ophiiiriden und Bemerkimgen zu bekannten. Ann. K. K. Naturhist. Hofmuseums, 11, 1887, p. 301) has. Fig. 28. Ophionereis sexradia, Part of oral side {a) and dorsal side {b). -20. recorded a small specimen of Ophionereis reticulata from " Westafrika". It appears, however, that there must be some error in regard to this specimen. The locality given for it, 0° 7' N, 23"^ 25' W, is about in the middle of the Atlantic Ocean in very great depths. That an Ophionereis reticulata (or any other Ophionereis) should occur here may well be said to be out of the question, and the label of this specimen must evidently be wrong. If Ophionereis reticulata does actually occur off West Africa it is rather strange that it has not hitherto been met with there. At any rate, Ophionereis sexradia is the first species of Ophionereis that has been actually found to occur on the West African coast. Ophionereis novae-zelandiae, St. 934. 17. viii. 32. 34° 11' S, 172° 10' E, Cook Strait, New Zealand, 98 m. 1 specimen. Diameter of disk 4 mm.; arms ca. 30 mm. long, thus some seven to eight times the diameter of d
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