. Discovery reports. Discovery (Ship); Scientific expeditions; Ocean; Antarctica; Falkland Islands. 368 DISCOVERY REPORTS Nova specimens of this subspecies in January, and in the Challenger specimens of the subspecies globosa, also in January. Polymastia isidis, Thiele. One specimen, collected on July 17, contains numerous sperm morulae, 0-045 n^"^- ^^ diameter, in the inner tissues, and indications near the surface that budding was about to begin. Around the outer ends of the bundles of the main skeleton are gathered masses of cells of a peculiarly yellow and granular appearance, and if
. Discovery reports. Discovery (Ship); Scientific expeditions; Ocean; Antarctica; Falkland Islands. 368 DISCOVERY REPORTS Nova specimens of this subspecies in January, and in the Challenger specimens of the subspecies globosa, also in January. Polymastia isidis, Thiele. One specimen, collected on July 17, contains numerous sperm morulae, 0-045 n^"^- ^^ diameter, in the inner tissues, and indications near the surface that budding was about to begin. Around the outer ends of the bundles of the main skeleton are gathered masses of cells of a peculiarly yellow and granular appearance, and if we may judge from Eichenauer's (1915) work on Tethya maza, Selenka, these are groups of amoebocytes (? archaeocytes) which will eventually form the bulk of the substance of the buds. Sphaerotyliis antarcticus, Kirkpatrick. Very young specimens are recorded by Kirk- patrick (1908, p. 17) which were collected in January, June and September o b b' Fig. 55. Embryonal megascleres of a, Plocamia gaiissiana, Hentschel; b, Dictyociona discreta (Thiele); c, Anchiiwe hptochela (Hentschel); d, Kirkpatrickia variolosa (Kirkpatrick); e, Ashestopluma calyx, Hentschel. All x 500, except e, which is x 400 {b' and c' are developmental stages). and as these young specimens were approximately of the same size, it is probable that some form of reproduction goes on in this species all the year round. This is probably an asexual budding. S. schnemis, Sollas, was also recorded by the same author to be actively budding in January. Spongia magellaiiica, Thiele. A specimen, collected on March 24, contains a number of spherical embryos, 0-07 mm. in diameter, showing a marked similarity to those of Hircinia variabilis, war. flavescens, figured by Schulze (1879, pi. iii, fig. i), and especially to the one in the bottom left-hand corner of the figure. A clear area, spherical in outline, is readily discernible at one pole of the embryo. The embryos are found chiefly on or near the principal fi
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