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Show 494 MR. E. T. BROWNE O N [Mar. 17 bulbs, without tentacles, one of the bulbs bas a short cirrus; and also four interradial and eight adradial bulbs, without cirri. Eight marginal vesicles, with a single otohth, situated close to the perradial canals. This medusa is clearly a very early stage, not long liberated from a hydroid. The presence of cirri tends to show that it mav develop into a medusa like Saphenia, or may bud two more tentacles and become like Eutima. As it resembles Saphenia in its present condition, I have placed it here until the hydroid form is identified. At the end of M a y 1895 I found twro specimens in Valencia Harbour. The smaller 4 m m . in diameter. As this medusa has been so little described, I give the characteristic points of the largest specimen (PI. XVII. fig. 3):-Umbrella 9 m m . in width and 5 m m . in length. Manubrium about 10 m m . long. The two opposite, perradial tentacles about 15 m m . in length, when fully expanded; twelve to fifteen marginal bulbs in each quadrant of the umbrella; the tentacles and all the bulbs with cirri. Eight marginal vesicles with 3-5 otoliths. The medusa is completely colourless, except for a delicate pinkish tinge on the stomach and lips. DISTRIBUTION. Scotland-Firth of Forth, Wright. England-Plymouth, Cunningham; Bles; Garstang; E.T.B. Isle of M a n , Browne. Ireland-Valencia Island, E. T. B. OCTORCHIS GEGENBAURI, Haeckel. Octorchis gegenbauri, Haeckel (1864) (1879). A single specimen of this medusa was taken, for the first time in British Seas, at Plymouth on 7th September, 1895. Only two species-0. gegenbauri and 0. campamdatus-are known and are only recorded from the Mediterranean. The Plymouth Octorchis does not correspond exactly to tbe descriptions given by Haeckel of either the above species, but appears to be an intermediate form, a kind of connecting link between the two species. As it is more like 0. gegenbauri, I have placed it under that name. Umbrella bell-shaped, 6 m m . in length and 9 mm. in width. Manubrium when fully expanded 12 m m . long. Peduncle quadrangular, about five times as long as the stomach; mouth with four large, crenate lips. Eight tentacles (4 perradial and 4 interradial), about 10 m m . long when expanded, about 2 m m . loug when contracted, without cirri at the base. About 60 bulbs, or warts, evenly distributed on the margin of tbe umbreha, nearly every one wdth short spiral cirrus. Eight marginal vesicles, adradial, with 6 to 10 otoliths in tw^o rows. On each of the four radial canals, about the middle of the peduncle, there is an oval mass of ova, and also a genital band, probably containing spermatozoa, extending along the radial canals from the base of the peduncle nearly to the margin of the umbrella. Medusa perfectly colourless. |