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Show 486 MR. E. T. BROWNE ON [Mar. 17 Between every bulb and tentacle six to ten cirri, very small and colourless. Scattered on the ex-umbrella, just above the margin, are numerous cirri, such as Forbes described. Eight adradial marginal vesicles, with about twelve otoliths in each. The gonads are upon the four radial canals, extending from the stomach nearly to the margin of the umbrella. The basal bulbs of the tentacles and the large bulbs without tentacles are alike in colour ; a yellow centre nearly surrounded by a purplish band. I sent to M r . E. J. Allen, at Plymouth, a description of these medusae taken at Valencia, and asked him to collect specimens for me. H e kindly sent m e seven specimens, alive, and some more in formaline, on June 28th. They were similar to the specimens taken at Valencia. The marginal vesicles contained a few more otoliths, arranged in some specimens in two rows. The stomach, mouth, and gonads purplish in colour. The tentacle-bulbs were coloured exactly like those of the Valencia specimens. There were cirri upon the ex-umbrella near the margin, and also between the tentacles. Diameter of the umbrella 10 to 15 m m. During a visit to Plymouth, in 1893, I saw some specimens of a medusa, labelled Laodice cruciata, taken by Mr. Garstang. Some of these specimens are now in m y collection. They show the cirri on the ex-umbrella near the margin, and agree in other details with the description given by Forbes. The marginal vesicles are not to be seen, as the specimens are in alcohol. I have proved over and over again that the marginal vesicles often shrivel up in spirit-specimens. Therefore, the absence of vesicles in spirit-specimens does not prove their absence in living specimens. During a visit to Plymouth in September, 1895, 1 found in the tow-net a very young medusa, which I believe, from the coloration of the tentacle-bulbs, m a y possibly be the earliest free-swimming stage of Euchilota pilosella. (PI. X V I . figs. 7 & 7a.) Umbrella bell-shaped, about 1 m m . in length and width. Eight marginal vesicles, with a single otolith in seven of them and two otoliths in the other one (the number of otoliths increases with age). Two opposite perradial tentacles, very short, and two opposite perradial bulbs, without tentacles. The basal bulbs of the tentacles are alike in coloration, a yellowish centre with a purplish band : the bulbs without tentacles colourless. The mouth has four lips, and the stomach extends into the substance of tbe umbrella, terminating in an apical stalk, which shows that the medusa has not long been liberated either from another medusa or from a hydroid colony, in this case probably from the latter. I placed this medusa in an aquarium ; nine days later the apical stalk bad disappeared, but the tentacles remained in same condition. I think there should be no difficulty in identifying Euchilota pilosella. The cirri upon the ex-umbrella near the margin and the eight marginal vesicles distinguish it from any other species, |
