TETRAXOXIDA. 37 



massive flabellate body 17 cm. high, tl cm. broad, and 7 cm. thick; a second 

 specimen is massive and spheroidal, 1 icing about 15 cm. in diameter. The white 

 maiumillatecl surface covers a reddish flesh in which the glistening fibres of the 

 skeleton are visible. The mammillae are on an average about 75 cm. in height, 

 and 1 cm. in diameter at the base. The new species bears a very close resemblance 

 to Mycale magellanica Ridley, which likewise has a mammillated, finely reticulate 

 surface and glistening skeletal fibres, but in the latter the surface is smooth and not 

 hispid (XX. 2), and the megascleres are styles, or sub-tyles, such as are normally found 

 in the genus Mycale. The microscleres also are different in the two species. 



A second species of Mycale with oxeate megascleres is Mycale intermedia (0. Sch.), 

 from East Greenland (16. p. 433) and Thiele (22. p. 381, fig. 12). The specimen 

 consisted only of a fragment ; the spicules, which are all considerably smaller 

 than in the Antarctic species, have the following dimensions: Oxeas, 450 M long, 

 10-12 /* thick; large auisocheles, 50-60 n long; small anisocheles, 18 /u long. 



Specimens were dredged from three separate localities near Winter Quarters, 

 viz.: (1) No. 6 hole, 125 fins.; (2) No. 12 hole, 25-30 fins.; No. 5 hole, seal 

 hole, 178 fins. 



MYCALE, sp. 



Several pieces of glistening white skeletal framework were dredged from No. 12 

 hole. The largest is cylindrical, 7 cm. long and about 3 cm. in diameter. A very 

 small quantity of the body substance still remains in some of the angles of the 

 meshwork. 



The spicules are: Styles, fusiform, straight, abruptly pointed, 5G2 x 17'5/u; 

 large palmate auisochelae, separate or in rosettes, 100 /x long and 35 M broad, with 

 the larger tooth 47 M long, nearly the same length as the alae, triangular, with 

 straight lower border; with the central tooth at the smaller cud squarish, 

 with straight upper edge; small anisochelae, 14x48/u, with oval tooth 28 n long, 

 extending further than the alae; sigmata 224 /u long, 104^ broad, and G'5/u thick. 



This species resembles in many respects a form described by Thiele (23- p. I !". 

 fig. 61, a-d) as Mycale sp., from Puuta Arenas, Straits of Magellan ; but the sigmata 

 are much smaller in the South American form, being only 15 /j., and the small 

 anisochelae are smaller and with a narrower and shorter upper central tooth. No 

 specific name is given, owing to the incompleteness of the specimens. 



Dredged near Winter Quarters, No. 12 hole, 25-30 fins. 



DESMACIDON KERGUELENENSIS var. antarctica. 

 (Plate XIX., figs. 1, IA, and Plate XXIII., figs. la-d l .) 

 Desmacidon hfirguelenmsis Ridley and Dendy (15. p. 110). 



Sponge ovoid or cylindrical, with hispid or finely conulatcd surface, the couules 

 surmounted by fine tufts of spicules, couules and tufts rising to a height of 1 to 2 mm. 

 Consistence, soft ; colour in spirit, dirty white. 



