DISCOVERY REPORTS 



MARINE BIOLOGICAL STATION 



St. MS 14. 17. ii. 25. From 1-5 miles SE by S to 1-5 miles S 1° W of Sappho Point, East Cumber- 

 land Bay. Small dredge, 190-110 m. 

 Homaxinella supratumescens (Topsent). 



St. MS 68. 2. iii. 26. East Cumberland Bay, South Georgia, from 17 miles S r E to 8| cables 

 SE by E of Sappho Point. Large rectangular net, 220-247 m. 

 Rossella nuda, Topsent. hodictya cactoides (Kirkpatrick). 



St. MS 71. 9. iii. 26. East Cumberland Bay, South Georgia, from 9I cables E by S to i-2 miles 

 E by S of Sappho Point. Small beam trawl, 120-60 m. 



Cinachyra baibata, Sollas. Myxilla mollis, Ridley and Dendy. 



Mycale frideiis, Hentschel. 



Saldanha Bay, South-west Africa (beach). 

 Haliclona Stephens!, sp.n. Hymeniacidon carunada, Bowerbank. 



DESCRIPTIONS OF SPECIES 



Phylum NUDA 



Order HEXACTINELLIDA 



Family ROSSELLIDAE 



Genus Rossella, Carter 



Rossella antarctica, var. intermedia, n. (Fig. 3 b, p. 257). 



Occurrence. St. 42: South Georgia, 120-204 m.; St. 152: South Georgia, 245 m.; St. 156: South 

 Georgia, 200-236 m.; St. 175: South Shetlands, 200 m.; St. 187: Palmer Archipelago, 259 m.; 

 St. 190: Palmer Archipelago, 93-130 m. 



Remarks. The six specimens present are all immature forms obtained from South 

 Georgia and the South Shetlands. The smallest is about i cm. in diameter and the 

 largest no more than 7 cm. high. In most respects they are quite typical of the species, 

 but their method of attachment leads to a number of interesting considerations. Two of 

 the specimens have the normal tuft of basalia, a third is without the basal half of the 

 sponge, and the three remaining are without basalia but have anchored themselves to 

 pieces of black volcanic rock. 



Two forms of R. antarctica have been known hitherto, var. antarctica from the 

 Antarctic and var. solida from the Kerguelen region. In the present group of specimens 

 we have a third variety which is intermediate between these two, suggesting that they 

 are no more than geographical varieties of a single species. The main differences between 

 the var. antarctica and the var. solida are that in the former there is invariably (?) a basal 

 tuft, that the velum is more strongly developed and that the rays of the pentactin pleuralia 

 are more or less cruciform ; whereas in the latter, the sponge is always attached directly 

 to the substratum, the velum is but feebly developed and the rays of the pentactin 

 pleuralia are confined to a sector of about 140° (Fig. 3 b). The present specimens are 



