Report on the zoological collections made in the Indo-Pacific Ocean ...

628 COLLECTIONS FEOM THE WESTEEN INDIAN OCEAN.CALCAREA.No Calcarea from this district are recorded in Hackel's ' Kalkscliwamme'(1872); but SchufFner (Jenaisch. Zeitsch. xi.) in 1878described several species from Mauritius, where they were collectedby Prof. Mobius.LEUCONIDtE.Two very widely distributed known species, a second speciesadded to a hitherto monotypic genus (Leucortis), and a knownMascarene species, all belonging to the Leuconida), represent in thiscollection the Calcarea of the Western part of the Indian Ocean.53. Leucetta primigenia, var. megalirrhaphis.Leucetta primigenia, var. megaraphis, Hdckel, KalkscMvamme, ii.p. 118.Two subglobular specimens 9 and 18 millim. in diameter, respectively,of the Dyssycus-ioTTo.. Colour in spirit pale brown.Hiickel states that this variety is rare, but does not give localities.In the specimen which I examined, the small triradiates are chieflyconfiried to a thin cortical layer.Hah. SeycheUe Islands, 12 fms.Distribution of species. Almost cosmopolitan.54. Lencaltis bathybia, Hdckel, var. mascarenica, nov.(Plate LIY. figs,a, a'.)Kalkschwdmme, ii. p. 156, pi. xxviii. fig. 2.Some specimens of the Ami?horiscus-iorm., composed of branchingand anastomosing tubes, cylindrical or somewhat compressed, 2*5to 3'5 millim. in diameter ; lumen 1-5 to 2*5 millim. wide, wallabout "5 miUim. thick. Colour duU umber-brown to cream-colour.The large quadriradiates are very large, viz. rays about '07 millim.thick, and rather short, with a long apical ray projecting into thecloacal cavity, and frequently a basal in the same plane but oppositeto the apical ; the small triradiates and quadriradiates are very small,viz. rays about "007 millim. thick, and most commonly have theforms figured in figs. 2 c, 2, d of Hackel's plate (I. c), viz. with verylarge facial angle. The larger triradiates are usually regular, andtheir rays are about "04 millim. in diameter. The slight thicknessof the body- wall, the proportions of the spicules, and the generalform of the specimens (which is simply cylindrical in Hackel'sspecimens) distinguish this form from varr. perimina and arabica,Hackel ; but in the straight or but slightly curved spicular rays itapproaches most closely the latter variety.Hah. Darros Island, Amiranto group; SeycheUe Islands, 4-12 fms.Distribution of species. Red Sea (Bdchel) ; Port Jackson (Part I.,p. 482, of this <strong>Report</strong>).