14 R. KIRKPATEICK. 



7/A in length, each ending in a convex disk-shaped capitulum, from which arises a 

 circle of disk-tipped secondary rays in two lengths. 



The new species comes very near to R. podagrosa, which it closely resembles 

 in general shape, in the characters of the orifice and of the marginalia and basalia, 

 and might perhaps be regarded as a strongly marked variety of that species ; but 

 B. liexactinopMla diflfers from R. podagrosa in having hexactin autodermalia ; in having 

 very much larger calycocomes with elongated cylindrical capitula, the capitula in 

 R. podagrosa being more or less hemispherical ; and in having oxyhexasters with 

 extremely slender secondary rays. 



Antarctic Circle, Long. 155° 21' E., 464 m. (254 fms.). 



EOSSELLA RACOVITZ^. 



(Plate L, fig. 5, and Plate IV., figs. 1-7.) 

 Rossella racovitzce, Topsent (11, p. x., and 12, p. 33). 



The collection contains only one example of this species, which appears, however, 

 to have been common in the region explored by the ' Belgica,' since no less than ten 

 specimens and fragments were obtained in four hauls. 



The present specimen is 16 mm. in length and 13 mm. in breadth, not including 

 the pleuralia, which extend 8 mm. from the surface. 



The ' Discovery ' specimen differs in several respects from those described by Topsent. 



The principalia are diactins with roughened rounded ends, sometimes swollen. 



The autodermalia are pentactins and stauractins, hexactins being absent ; the 

 rays are thick, slightly spined and a little swollen at the ends. 



Just below the surface, along with the oxypentactins, are many thick curved 

 diactins 1080 x 12/x. 



The oxyhexasters are not remarkable except in the smallness of their numbers ; 

 they appear to be replaced by the discohexasters. 



The calycocomes are 225/* in diameter, whereas those of the ' Belgica ' are 400/li. 



The discohexasters, 168/* in diameter, are very abundant; the large disks at the 

 ends of the secondary rays attain a diameter of 16-20/i,, and have long sharp denticles; 

 these spicules present all the transitions from holodiscohexasters, through hemi- to 

 mono-discohexasters. 



The microdiscohexasters (rare), 56/i- in diameter, have the secondary rays of only 

 one length. 



'Discovery,' Winter Quarters, Flagon Point, January 17, 1903 ; Dredge 18-36 m. 

 (10-20 fathoms). 



The 'Belgica' Expedition dredged it in Lat. 70° 15'-7l° 15' S. Long. 80° 48'- 

 87° 39' W. 450-569 m. (247-310 fathoms). 



AULOROSSELLA. 



Sack- or barrel-shaped Rossellince with three kinds of discohexasters, viz., 

 calycocomes, medium discohexasters and microdiscohexasters, With surface conules. 



