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Show 1897.] MR. E. T. BROWNE ON BRITISH MEDUSA. 817 by Forbes upon the radial canals may possibly be parasitic Distoma. The specimen which I captured at Valencia helps to clear up these conflicting statements. It has generative cells upon the manubrium, as described by Haeckel, and it has also the linear swellings upon the radial canals, as described and figured by Forbes. There can be no doubt about the swellings upon tbe manubrium being formed of generative cells, but I a m not able to make a definite statement with regard to the swellings upon the radial canals. Sections show that the swelling is formed by a considerable enlargement of the endoderm cells, which are crowded with small nuclei. In general appearance the swelling resembles an immature gonad, as usually seen upon the radial canal of a Leptomedusa, but more specimens must be examined to settle the question whether there are generative cells among endoderm cells of the swellings or not. I have a few small specimens in my collection which have again been examined, and 1 have found in all of them traces of the swellings upon the radial canals. These specimens were preserved before examination and by a method not suitable for histological work. As the Valencia specimen does not agree exactly with the descriptions given by Forbes and Haeckel, 1 think it is best to describe it and give a figure of it, especially as Forbes has figured an immature stage:-Umbrella bell-shaped, about 8 m m . in length and 6 m m . in width. Manubrium, when expanded, very slender, about twice the length of the umbrella, with a small apical knob. At tbe end of each of the four tentacles there are large batteries of nematocysts, forming a large terminal knob when the tentacle is contracted (fig. 2 h); but when expanded (fig. 2 a) the terminal knob is seen to be composed of three distinct clusters of nematocysts. The basal bulb of the tentacle is of a dark reddish brown, with a large black ocellus. Two masses of spermatozoa surround the manubrium, one extending from the mouth along the stomach, and occupying about one third the length of the manubrium, the other starting a short distance away and occupying another third of the manubrium. On each of the four radial canals, at about one third of the distance from the stomach to the ring-canal, is a small linear swelling, which Forbes regarded as an ovary, but that statement still needs confirmation. ? CYT.EANDRA AREOLATA, Haeckel. (Plate XLVIII. figs. 1,1a, and 2.) In m y Beport on the Medusae of the Isle of M a n (Trans. Liverpool Biol. Soc. 1895), I have described under the name of Cytce-andra areolata several stages of a medusa which has not yet been figured. I erred somewhat in using the name Cytceandra areolata for this medusa. It is Haeckel's name for the medusa budded off from the hydroid Podocoryne areolata (Alder), but up to the present there is not the slightest proof that m y specimens are derived from that hydroid. I have but little doubt that eventually they will |