. Contributions to the natural history of the United States of America. Zoology; Chelonia (Genus); Ctenophora; Cnidaria; Animals. Chap. II. AURELIA FLAVIDULA. 49 Fuj. Longitudinal sectional view of the Eye of Aurelia FLAVIDULA, corresponding to Firj. 11, PI. XIc; designed from nature by H. J. Clark. there is a single tentacle (1) and two tentacular lobes (/^), one on each side; in the distance are two smaller tentacles (2 and 2"), one contracted, and the other extended, whose bases have a common wall (t) directly below the large single tentacle just mentioned; and finally there is a t
. Contributions to the natural history of the United States of America. Zoology; Chelonia (Genus); Ctenophora; Cnidaria; Animals. Chap. II. AURELIA FLAVIDULA. 49 Fuj. Longitudinal sectional view of the Eye of Aurelia FLAVIDULA, corresponding to Firj. 11, PI. XIc; designed from nature by H. J. Clark. there is a single tentacle (1) and two tentacular lobes (/^), one on each side; in the distance are two smaller tentacles (2 and 2"), one contracted, and the other extended, whose bases have a common wall (t) directly below the large single tentacle just mentioned; and finally there is a third tentacle (5), still further in the distance and on the extreme left, whose walls unite, at the base (t), obliquely upwards and laterally, with those of the longer tentacle (2'') of the second row. Beyond all these the lower margin (s) of the socket may be seen. The length of the tentacles, when they are fully extended, is about one third of the radius of the disk; they are quite slender and frequently coil upon themselves in spiral tresses. The next phase is the last of the series which we have studied connectedly. At this age (PI. XI". Fic/s. 1, 2, 7, 8, 9, and 11; and Fig. 1) the diameter of the disk is very nearly an inch and a half, and there are fifty tentacles on each mar- ginal segment. The essential addition to the organization is the development of two tubu- lar prolongations (PI. XP. Fig. 2 cl^, Fig. 11 d^) of the radiating canals, in each ocu- liferous lobe. These tubes are formed in the same way as the canals from which they arise, and are peculiar in shape ; starting at an angle of forty-five degrees to the canal of the lobe, each one projects, for one half of its length (« y), in a straight line, into the midst of the lappet, and then bending (y) slightly inwards, proceeds as far again, and a closed end. Like the chymiferous canals, these blind tubes are embraced by a single wall (C r), above and below. The exterior edge {Figs. 8 and 11
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