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Show 1897.] MR. E. T. BROWNE ON BRITISH MEDUS.E. 829 No. 1. Umbrella 25 nun. in diameter. The stomach is very broad at the base, which is slightly convex in shape, and about 13 m m . in diameter. The mouth has about 55 simple folds, and, when expanded, is 7 m m . in diameter. No less than 140 radial canals leave the stomach, and out of these 45 enter the ring-canal, the remainder showing various stages in development. At this stage the generative cells are just visible upon some of the canals. Upon the margin of the umbrella there are four large tentacles, when expanded about 20 m m . in length, situated at about equal distance apart, and there is also a small tentacle, about midway between the large tentacles, in three of the quadrants. The fourth tentacle, to make this series complete, has not yet begun to grow. In addition to the tentacles there are about 100 marginal bulbs, varying in size, from which tentacles develop in the later stages. The marginal vesicles are very numerous, but not constant in number and position, generally two between every two bulbs. No. 2. Umbrella 30 m m . in diameter. This specimen shows a later stage in development as there are 8 large tentacles, but the numbers of marginal bulbs and vesicles are about the same as in the first specimen. The radial canals are not nearly so numerous, only 114 present. About half enter the ring-canal, the others show various stages of growth and usually alternate with the former. In one place on the umbrella there is a union of four adjacent canals, which again branch into three canals. No. 3. Umbrella 55 m m . in diameter. The base of the stomach shows a well-marked convexity, 26 m m . in diameter, which is formed by a thick mass of mesoglcea. There are 16 tentacles present, which may be divided into three sets- four very long, four moderately long, and eight very short. Nearly all the radial canals (145 in number) unite with the ring-canal. The gonads, o\\ ing to their increase in size, are conspicuous, and the marginal bulbs and vesicles are very numerous, as in the preceding specimens. No. 4. Umbrella 60 m m . in diameter. The base of the stomach measures 33 m m . in diameter and has a conspicuous convexity. The stomach itself, though very broad, is very short, and the mouth measures 17 m m . in diameter when expanded. There are 28 tentacles, varying in length, eight of which are very long, and about 40 marginal bulbs. The radial canals, about 180, nearly all unite with the ring-canal. One canal on leaving the stomach divides into three branches, and another into two branches. The generative cells show a further stage in development. No. 5. Umbrella 135 m m . in diameter. The first four specimens show a gradual increase in size and in development, but there is a slight gap in the series between this specimen and the last one. The umbrella is very flat on the top and about four times as broad as high. The growth of the stomach, |