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 respectively. 



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 fibres of the skeleton. 



POST-LARVAL DEVELOPMENT 



Tetilla leptoderma (Sollas). There is a single small specimen from St. WS 27 which 

 measures 3 mm. in diameter. The skeleton consists of radiating bundles of oxea, pro- 

 and anatriaenes, which start from an excentrically placed nucleus. The form of the 



