TKTKAXONIDA. 53 



There are six specimens and fragment*. Tlie outward appearance varies greatly 

 according to age and size. In one small specimen the surface is finely hispid, in larger 



eonuloee, anl in very large ones conulated and with high meaudrine ridges. The 

 jKM-imen N". I I - i I'l. \\lll . ii-j. 1 ) ll in iv BoRH "I i \\ i.L- thick \\.-ill-.i till*', 

 1-J cm. hiizli and G cm. in diameter, and with walls 1 '5 cm. thick, but attenuating towards 

 the rim <>f tin- tuln?. This specimen is incomplete IH?!OW. The orifice is circular, and 

 \\iihin the rim is a (liaphntgni contracted to a white line. 



The sui: overed with large conulcs and meandrinc ridges rising to a height 



of nearlv I cm. 



Tin* dermal membrane, in the spaces between the conules and ridges, shows as a 

 line lace-like reticulum, with circular pores 133 M in diameter, and Itencath it the 

 i>i Slices (1-1 '5 mm. in diameter) of the inhalant canals arc visible. The cxhalant 

 orifices on the inner wall of the tube are much larger than the inhalant ; they vary 

 from 1 to 6 or 7 mm., their edges are smooth and rounded. In the second largest 

 specimen, these orifices are arranged in longitudinal rows, and are oval with the long 

 diameter vertical. This arrangement results from the way in which the contraction 

 of the tubular sponge body is restricted by the main longitudinal skeletal fibres 

 running beneath the inner surface. 



In a third specimen (No. 132), the outer surface of the wall is almost smooth to 

 the naked eye, though under a lens it is seen to be finely hispid, with the top of oxeas 

 projecting from minute conules. 



In another specimen the Ixasal part of the sponge divides into two tubes, one 

 of which is nearly smooth, and the other with ridged surface. 



The species closely resembles R. spinosella, Thiele (23. p. 459), from Punta 

 Arenas. In Thiele's species the body is tubular, with conulated surface, and the texture 

 is rery soft ; but the skeletal framework is irregular, and the oxeas, though similar in 

 form, are much shorter, smaller and more slender, l>eing only 150-170 /* long and 

 7-8 /i thick. 



Another species showing certain resemblances to R. scot 1 1, viz. R. aquaeductu* 

 Schmidt, var. infundibular if (R. and D.), has a unispicular skeletal network. 



Specimens were dredged near Winter Quarters, in No. 12 hole, 25-30 fms. ; S.E. 

 of Cape Armitage, 100 fms. ; off Flagon Point, 5-25 fms. ; off E. end of Ice Barrier, 

 100 fms., mud and stones. 



REXIERA DANCOI. 

 (Plate XVIIL, fig. 3.) 

 1901. Rmitra dancoi, Topwnt (29. p. 12, PI. II., fig. 1, and PI. III., fig. 8.) 



There are two specimens. One is of a compressed digitate form, 10 cm. long, 

 2 ' 5 cm. wide, and 1 cm. thick. About the middle of one side is a projecting shoulder 

 with an oscule. Near, but not quite at the summit, on the opposite edge, is 

 a second oscule. The specimen is contracted at the centre; the alternate oscules 



