Excerpt from The Craspedote Medusa Olindias and Some of Its Natural Allies

The umbrella is moderately high, measuring nearly one-half as much as its largest diameter, which is found slightly above the margin (pl. I, Fig. But in younger examples (fig. 2) it is relatively higher, as in many other veiled medusa. The jelly is. Thick and very consistent. The manubrium is quadrate with distinct lips, and when expanded hangs down into the umbrella cavity about two-thirds the height of the latter. Of some forty specimens that I have examined for the purpose, only three had four radial canals, and all the rest had six, so that there cannot be any doubt that six is the normal number for the species. Two of the canals start from two of the opposite corners of the manubrium, and of the remaining four two together from the other opposite corners. A comparison of a few examples is, however, suffi cient to show that the number six is due to the bifurcation of two of the four original radial canals. This is easily seen on the apical view of almost any example, as shown in Figure 7, where two of the radial canals are seen to unite just before enter ing the central stomach, or as in Figure 8, where four of the radial canals forming opposite couples are seen to have a common root for each couple. Examples with two simple and two Y-shaped radial canals are not rare, and cases of five radia canals are also met with, though seldom.

The gonads are foldings of the subumbrellar walls of the radial canals, and extend the greater part of their lengths, leaving only a small proximal portion and a much smaller distal portion free (fig. In young examples these foldings are very simple and are clearly continuous (pl. II, Fig. But in older ones they become more complicated and are sometimes divided into numerous lobes, which are again subdivided into secondary lobes (pi. I, Fig. In the case of Y-shaped radial canals, the gonads extend upwards only as far as the point of division, and are therefore V - shaped. If the point of division lies very near the manubrium, however, the gonads leave a small proximal portion free, as in the normal case.

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