. Discovery reports. Discovery (Ship); Scientific expeditions; Ocean; Antarctica; Falkland Islands. A B Text-fig. 10. Physalia physalis. Nematoblasts. A, from the ampulla, capsule diameter 27 ft. B, from the ampulla, capsule diameter 11 [i. n = nucleus. nucleolus of the cnidoblast or mother-cell are clearly visible at the inner end. In immature cnidocysts there is a large, central, homogeneous, hyaline mass at the circumference of which the thread can later be seen developing. Surrounding this central mass is a clearer, transparent substance which presumably forms the capsule wall. In 1926 Wil
. Discovery reports. Discovery (Ship); Scientific expeditions; Ocean; Antarctica; Falkland Islands. A B Text-fig. 10. Physalia physalis. Nematoblasts. A, from the ampulla, capsule diameter 27 ft. B, from the ampulla, capsule diameter 11 [i. n = nucleus. nucleolus of the cnidoblast or mother-cell are clearly visible at the inner end. In immature cnidocysts there is a large, central, homogeneous, hyaline mass at the circumference of which the thread can later be seen developing. Surrounding this central mass is a clearer, transparent substance which presumably forms the capsule wall. In 1926 Will published, without figures, an interpretation of what he thought to be the earliest developmental stages, but there still remains doubt about the details.* Chun (1892) had published figures of immature, tentacular cnidoblasts which show the 'tube externe', a feature that was puzzling until Weill (1934) showed that it was only the prematurely devaginated thread of an immature nematocyst. In many immature cnidoblasts I have seen the thread of the nematocyst partially devaginated in coils in the body of the cnidoblast as figured by Chun. The thread of the nematocyst is frequently found in preserved material to be devaginated while * In my opinion nothing is known yet about normal nematogenesis in any Cnidarian, except that the nematocyst originates as a homogeneous secretion-mass in an ectodermal mother-cell (nematoblast).. 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 perfectly resemble the original Institute of Oceanographic Sciences (Great Britain); National Institute of Oceanography of Great Britain; Great Britain. Colonial Office. Discovery Committee. London ; New York : Cambridge University Press
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