. Discovery reports. Discovery (Ship); Scientific expeditions; Ocean; Antarctica; Falkland Islands. PATTERN OF BUDDING 333 I call lateral groups. Whether he was also referring to the series (4) arising from the bases of the lateral groups is not clear. The development of group 2 and the subsequent lateral tripartite groups can best be seen in the aboral region of the main zone by examining cormidium I of a young specimen (PI. XIV, figs. 2-3). This region looks very complicated in older stages (PI. XIV, fig. 4); when mature it is almost impossible to analyse this first cormidium without knowled
. Discovery reports. Discovery (Ship); Scientific expeditions; Ocean; Antarctica; Falkland Islands. PATTERN OF BUDDING 333 I call lateral groups. Whether he was also referring to the series (4) arising from the bases of the lateral groups is not clear. The development of group 2 and the subsequent lateral tripartite groups can best be seen in the aboral region of the main zone by examining cormidium I of a young specimen (PI. XIV, figs. 2-3). This region looks very complicated in older stages (PI. XIV, fig. 4); when mature it is almost impossible to analyse this first cormidium without knowledge of the younger stages. Cormidium I has room to expand because it lies at the aboral end of the main series, consequently the primary and lateral groups, especially the first, are better developed and more widely separated than those of the other cormidia. Its aboral end forms a projection (PI. XIV, fig. 3) on which the youngest groups can be seen. Two GZ OF GON,. u2 mm Text-fig. 15. Physalia physalis. Cormidium 5 (oral zone) of a young specimen number 11, less group 1, to show the three parts, A, B, C, of an 'Urgruppe'. Note the endodermal villi. GZ of = gonozooid mentioned on p. 347. XII. beautiful young specimens, measuring 2-9 and 8 cm. in float-length, show clearly that at this stage there are at least eight lateral groups in cormidium I. They decrease in size according to youth, so that the one at the aboral end is a very small bud (PL XIV, fig. 3). Each group consists of a gastrozooid, a gonodendron and a tentacle. They look as if they might be, and indeed at one time I thought they were, beginnings of new cormidia, but in each of the other cormidia of the main zone there is a counterpart of this series of lateral groups. As previously stated, there is evidence that the latest (youngest) cormidia to appear do so at the oral end of the budding-zone, whereas in the lateral groups the pattern of development is reversed, the youngest groups appearing at the aboral en
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