British Museum. by JANES YATE JOHNSON, C.M.Z.S. NO. LIII
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1899.1 ON THI ILNTIPAl'HARIAN CORALS OF MADBIBA. 813 11. Notes on the Antipatharian Corals of Madeira, with Descriptions of a new Species and a new Variety, and Remarks on a Specimen from the West Indies in the British Museum. By JANESYATE JOHNSON, C.M.Z.S. [Received May 22, 1899.1 The marine objects popularly called Black Corals are zoophytes which constitute the group of Antipatharia in systematic z001og~. Some of them are much branched and resenible bushes that occa- sionally reach the height of four or five feet. Others extend their branches almost in one plane in a fan-like manner ; others, again, are simple unbranched stems, slender and wire-like, that are some- times found with a length of seven or eight feet. All are attached, when living, to submarine rocks or stones by a thiu spreading base. All have Ihard horny axis of a black or brown colour, and that axis is seen, on examining a section, to consist of concentric layers. Further examination will show that it has tt fibrous structure. Stem and branches are frequently armed with' minute spines arranged in longitudinal or spiral series, but sometimes the stem and inain branches nre amooth and polished. The hard axis is Necreted by the soft polypiferous ccenenchyma which clothes it. The polyps in the Madeirnn forms have six (in one species twenty- four) simple tentacles. Spicula are not anywhere present, and thus the Antipatharia are easily distinguished from the Alcyouaria. Eight species of Black Coral belonging to six genera have beeu found at Madeira, more than one-thirteenth of the total number of known species. In the late George Brook's excellent Report on the Antipatharia of the ' Challenger ' Expedition (1889) ninety- eight species were dealt with, but these included not only the forms collected by the naturalists of that expedition but all those pre- viously described. The Report iq therefore a Monograph of the group. Until the publication of that work much difficulty was experienced in comiug to a conclusion with regard to the discrimi- nation of species and the identification of specimens, owing to imperfect description and confusion of nomenclature ; and even now, notwithstanding that author's efforts, much remains to be clone, especially in regard to our knowledge of the polyps, before satisfactory definitions are possible and the classification placed on a trustworthy basis. All the species of Madeira come from depths below 40 fathoms They are brought to the surface by becoming entangled now and then in the lines of the fishermen. Of the eight species of Black Coral bere treated of, five have not hitherto been found elsewhere, and one of these is now described for the first time (Leiopathes eqansci). Another of the five species, having been confused with a West Indian species, is here distinguished by a fuller description, whilst a new name has PBW. ZOO&. soCr.-1899, NO.LIII. 53 814 MR. J. Y. JOHNSON ON WPl [June 20, been necessarily imposed on the tropical form. Furthermore, another of Gray’s species (Antipathes setacea) has been removed from the position it occupied of a queried synonym and is reestablished as distinct by a more detailed description. Two of the eight species here dealt with (Xavqlia Inmarchi and Leiopathes glaberrirna) are known in the Mediterranean, which great sea possesses apparently a smaller number of species than the sea immediately surrounding the diminutive island of Madeira, for it seems that not more than six forms can with certainty be attributed to the former. These are (in additiou to the two already mentioned as common to the two seas) Antipat7ies clichotonza Pall., A. ntecliterranea Brook, Anti- pathella subpinaata (E. & s.), and Parantipatlies larix (Esper). The existence in the Mediterranean of any elongate unbranched form like Cirripathes requires confirmation. Gen. SAVAQLIANardo, 1843. Corallum horny, without spines ; polyps with 24 tentacles in alternate rows of twelve each. SAVAGLIALAMABCKI (Haime). Savaglia lamarcki, Brook, Antipatharia of the ‘ Challenger,’ p. 79. Uerardia lamarcki, Lacaze-Duthiers, 1864. Leiopathes lamarcki, Haime, 1849. Moderately branched, furcately, in one plane. Axis black or brown ; trunk and branches very sinuous, not cylindrical, but com- pressed laterally so that the anterior and posterior faces are narrower than the intervening sides and the angles are rounded off. There is no groove on any of the faces or sides. The surface of the stem and main branches is seen under the lens to be minutely wrinkled and finely punctured, ilie punctures being numerous and irregularly scattered. The branches are elongate and tapering, very seldom fusing together. Only two specimens of this species have come under my obser- vation. Neither has a base. The smaller example has a height of 50 centim. (278 in.) and a spread of 45. It has beenentirely stripped of its polyps. The other is 85 centim. (32; in.) high, and the longer axis of the lower part of the stem measures 15 millim. It has lost moRt of its branches ; there are remains of the ccenosarc and polyps on the highest ones ; their oval mouths, with thickened lips marked by radiating grooves, are large and con- spicuous, the longer axis measuring 4 millim. There is some doubt as to the true zoological position of this organism. The horny branched axis has all the appearance of being antipatharian, but the polyps with their 24 tentacles are closely allied to the Zoanthids, es ecially to the genus Parazoanthw Haddon & Shackleton. Carygren therefore has advocated the re- mopal of Uerardia lamurcki from the Antipathad to the Zmthidta 1899.1 ANTIPATEARIAN UOEALS OF MADEIRA. 815 (‘ Ueber die Qattung Gkardia,’ 1865), and PourtalBs in 1871 took the same view. In the ccenosarc of Mediterranenn examples of this species Lacaze-Duthiers found a peculiar cirripede which he named Laura gwardicP. This has not been observed in Madeiran specimens. Hab. Madeira ; Mediterranean. Gen. STICEOPATHBSBrook. Axis forming a long, slender, flexible rod without branches. Polyps arranged in a longitudinal series on one side of the stem, not distributed on all sides as in Cirripathes ; tentacles six. STICHOPATHESGBACILIS (Gray). Antipat7m (Cirripathes) yaracilis, Bray, P. Z. 8. 1857, p. 291. Stkhopathes gacilis, Brook, Antipatharia of the Challenger,’ p. 90. Jet-black ; the stem throughout armed with short conical spines at right angles to it, arranged irregularly in spirals (fig. 111. 1, p. 823). On the lower part of the stem there are about nine series. The base spreads thinly over the object to which it adheres, and is from 10 to 15 millim. in diameter. The lower part of the stem is usually from 3 to 4 millim. in diameter. This species is not of very rare occurrence. The individuals are commonly attached to a well-rounded stone or to masses of cal- careous sand cemented by shells, worm-cases, &c. One small specimen had seated itself on the spineless test of a dead sea-urchin (Avbmia). Two or more may sometimes be seen adhering to the same stone, and, indeed, I had once observed as many as twelve in- dividuals on the same block. But great was my astonishment when a stony niass, 10 in. by 5, was shown to me upon which were seated more than 120 specimens, in two groups, some 20 being sepnrated from the rest, which formed a grove so thickly planted that it was difficult to count them correctly. Unfortunately t,he majority were broken, leaving stems only a few inches long; the length of the perfect ones was about three feet. Two and even three distinct stems may spring from the same basal expansion. It may have been that the bases were at first separate and afterwards coalesced as they extended, but there was no evidence to show that this had been so. The largest specimen that has been met with at Madeira had a length of 9 ft. 3 in. (2820 millim.). This has been placed in the Seminario Museum, Punchal. In contrast with specimena of this size, young ones 6 millim. long have been found, and two of these have been mounted in balsam on a slip of glass. Brook says that the stem is sinuous but not spiral. Two speci- mens, however, are in my possession which in their upper part form a few very loose irregular spirals. They are on the same mass of indurated And, shells, worm-cases, &c. Normally the individuals of this species are destitute of branchee 5Y* 816 YR. J. Y. JOHNSON ON THR [June 20, but I have a specimen which has put forth a very slender spineless branch 150 millim. (nearly 6 in.) long. This abnormality was perhaps due to the fact that the upper end of the stem, four or five inches above the ramus, had been broken off by.some accident, and the branch may have been the result of an effort on the part of the colony of polyps to continue their growth. With regard to t,he spines, those of all the specimens I have seen are simple and conical, but Brook says that the majority of those on the older portions on the stems of specimens in the British Museum formed double spines. Hah. Madeira. STICHOPATHESSETAOEA Gray. Antipathes (Cirmpnthes) setacea, Gray, Ann. & Mag. N. H. ser. 3, vol. vi. p. 31 (1880). ? dntipathes simplex, Alcide d’Orbigny in Webb & Berthelot’s Hist. Nat. des Iles Canaries, Zoologie : Polypiers, p. 151. Dr. Gray’s description of his A. setacea runs thus :-rc Coral simple, elongate, setaceous, straight, erect, closely covered with short conical spinnles. Length 18 in. Hab. Madeira.” He said further that it was straight, without the slighest tendency to assume a spiral form. Mr. Brook (Antipatharia of the ‘ Challenger,’ p.