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Show 1896.] BRITISH HYDROIDS AND MEDUSAE. 463 Fam. PODOCORYNID^E. PODOCORYNE CARNEA, SarS. Hydroid Form. Podocoryne cornea, Sars* (1846); Hincks* (1868); Allman* (1872); Duerdin (1893); Garstang* (1894). Podocoryne albida, Sars (1846). Medusoid Form. Podocoryne carnea, Crawford (1895). Bysmorphosa carnea, Haeckel (1879) ; Browne (1895). Lizzia blondina, Bohm (1878). Sars first described both the hydroid and medusoid forms of Podocoryne carnea. Haeckel has, however, given the name Dysmorphosa carnea to the medusa. The medusa of Podocoryne carnea must not be confused with Bysmorphosa minima, Haeckel, which I believe to be the earliest stage of Lizzia blondina, Forbes. The latter has its stomach upon a peduncle, and medusa-buds are usually present upon the walls of the stomach in the early stages. At Plymouth, in September 1893, and again in 1895, I tried to rear the young medusae budded off from the hydroid colonies kept in glass jars. The experiments did not yield any results, as the medusae died off within a week. The young medusae do not all leave the hydroid colony with the same number of tentacles. All have four single perradial tentacles, but the number of interradial tentacles shows variation. The usual number is either two or three, but I have seen a specimen with only one tentacle. The interradial tentacles do not appear in any definite order. In some specimens the two interradial tentacles are opposite one another, in others they occupy adjacent quadrants of the umbrella. I have not seen a specimen with eight tentacles amongst those reared in m y jars, but have taken specimens in the tow-net. At Valencia, on April 10th, 1895, I took a specimen of the medusa with eight tentacles. DISTRIBUTION. Norway, Sars (H). Naples, Sars (H). Scotland-St. Andrews, M'Intosh ( M ) ; Craivford (M). Firth of Forth, Allman (H). England-Plymouth, Garstang and E. T. B. (H, M ) . Isle of Man, Browne (M). Ireland-Long Island Bay, Buerdin (H). Valencia Island, E. T.B. (M). Fam. COEIMOEPHIDJE. CORYMORPHA NUTANS, M. Sars. (Plate XVI. fig. 1.) Eydroid Form. Corymorpha nutans, M . Sars* (1835); Forbes and Goodsir (1840); Johnston (1847); Sars* (1859); Hodge * (1861); Allman* (1863) (1864); Hincks* (1868); Allman* (1872) |