(1) The stinging-cells on the tentacles of Limnocuida are not developed in situ but in the ectoderm of the "nettle-ring," whence they migrate to the tentacular batteries. The "nettle-ring" is to be regarded merely as the factory and storage-place of these stinging-cells, and is not itself a functional nematocyst battery.

(2) Limnocnida possesses a well-developed, double nervering at the base of the velum, it is similar in most respects to that of Limnocodium and of other medusæ.

(3) The manubrium is undoubtedly functional as a digestive organ. The gland-cells and digestive cells are restricted to the more proximal regions, the oral endoderm being characterised by the presence of an unusually large number of mucus-secreting goblet-cells.

(4) The development of the medusa-buds presents several interesting features, some of which are undoubtedly primitive. As originally described by Günther, the entocodon is formed by simple invagination; this causes the endodermal walls of the bud to assume the shape of a double - walled cup, which, almost simultaneously with its formation, becomes constricted at the interradii, leaving four large perradial pouches of endoderm, which give rise to the radial canals of the adult medusa. The manubrium appears very late as a rounded boss projecting into the umbrella cavity.

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