328 DISCOVERY REPORTS 



Family AXINELLIDAE 

 Genus Hymeniacidon, Bowerbank 

 Genotype. Hymeniacidon carunciila, Bowerbank, 1858, p. 286 {fide Thiele, 1905, p. 421). 

 Diagnosis. Axinellidae possessing styli only ; main skeleton a confused reticulation ; 

 with special dermal skeleton in form of tangential layer of irregularly scattered 

 spicules. 



Hymeniacidon caruncula, Bowerbank, Autt. 



Occurrence. On the beach, Saldanha Bay. 



Remarks. The two specimens appear to be identical with those described by 

 Stephens (191 5, p. 438) from the same locality. 



Distribution. From the Arctic down the eastern shores of the Atlantic to Saldanha 

 Bay. 



Hymeniacidon sanguinea (Grant), Autt. 



Occurrence. St. 271 : Elephant Bay, Angola, 0-5 m. 



Remarks. An orange-coloured sponge encrusting clumps of Ostrea. 



Distribution. North Atlantic and Arctic Oceans. 



Hymeniacidon fernandezi, Thiele. 



H.fernandezi, Thiele, 1905, p. 422; Topsent, 1913, p. 615, pi. iii, fig. 6. 



Occurrence. St. 53: Falkland Islands, 0-2 m.; St. 145: South Georgia, 26-35 "^-S ^t. 160: Shag 

 Rocks, 177 m.; St. WS 27: South Georgia, 106-109 m.; St. WS 84: Falkland Islands, 75-74 m.; 

 St. WS 85 : Falkland Islands, 79 m. 



Remarks. One specimen is growing amidst the branches of an alga, in company with 

 lophon unicornis. In external appearance it resembles the specimen figured by Topsent 

 {loc. cit.), while its skeleton is very like that of the holotype, with which I have been able 

 to make a comparison. The styli measure 0-3 by o-oo8 mm. 



A second specimen is massive and low-lying, encrusting fragments of shells. The 

 spicules measure 0-2 by 0-005 "^'^- ^^^ ^^^ sponge resembles very closely in appearance 

 and texture the specimens recorded above under H. carwiciila, Bowerbank. 



There is little doubt, as Topsent has suggested, that the present species has a close 

 affinity with H. caruncula, and it is difficult to see how a distinction between the two 

 species can be made except on the grounds of small differences in the size of their re- 

 spective spicules. Until the variations in H. caruncula have been carefully studied, 

 however, it is better to regard the two species as distinct. 



Distribution. Juan Fernandez; Falkland Islands. 



Hymeniacidon torquata, Topsent. 



//. torquata, Topsent, 1916, p. 166; id., 1917, p. 40. 

 Occurretice. St. 6: Tristan da Cunha, 80-140 m. 



Remarks. The single specimen is doubtfully assigned to this species. 

 Distribution. Petermann Island. 



