of the National Antarctic Expedition. 291 



Localities, Winter Quarters, 25-30 fatli. ; McMunlo Bay, 

 96-120 fath. 



Reniera Scotti, sp. n.* 

 Sponge consisting of one or more fistulas. Texture very- 

 soft and easily lacerated. (colour in spirit varying from 

 yellow to pale reddish. Outer surface varyitig from being 

 finely hispid to having large conules and meandrine ridges. 

 Inner surface of tistulaj very finely hispid in the spaces 

 between the numerous orifices of exhalant canals. Flagellated 

 chambers large, hemispherical, 60 x 10 /i. 



Skeleton formed of parallel longitudinal lines of main 

 fibres, about 2-6 spicules thick, curving outwards from the 

 inner to the outer surface, where they pass into the conules 

 and ridges ; secondary fibres at right angles to the maia 

 ones, one or two spicules thick. The spicules are not closely 

 united, and spongin is only present in very small amounts. 



Spicules. — Oxeas, 343 X 14-6 /i, curved or bent at centre, 

 subtornote. 



There are six specimens and fragments. The outward 

 appearance varies greatly according to age and size. In one 

 small specimen the surface is finely hispid, in larger nni's 

 conulose, and in very large ones conulated and with high 

 meandrine ridges. The largest specimen (No. 118) is in 

 form of a wide thick-walled tube, 12 cm. high and 6 cm. in 

 diameter, and with walls 1*5 cm. thick, but attenuating 

 towards the rim of the tube. This specimen is incomjjlete 

 below. The orifice is circular, and within the rim is a 

 diaphragm contracted to a white line. 



The surface is covered with large conules and meandrine 

 ridges rising to a height of nearly 1 cm. 



The dermal membrane, in the spaces between the conules 

 and ridge, shows as a fine lace-like reticulum, with circular 

 pores 133 fi in diameter, and beneath it the orifices (1-1*5 mm. 

 in diameter) of the inhalant canals are visible. The ex- 

 halant 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. 



The species closely resembles E. spinosella, Thiele, from 

 Punta Arenas. In Thiele's species the body is tubular, with 

 conulated surface, and the tixture is veiy soft; but the 

 skeletal framework is irregular, and the oxeas, though similar 

 in form, are much shorter, smaller, and more slender, being 

 only 150-170 /i long and 7-8 yu, thick. 



Localities. Winter Quarters, 5-100 fath. ; olf E. end of Ice 

 Barrier, 100 fath. 



* This Hne species is iianicd after Captain Scott, li.X., the leader of 

 the Expedition. 



