326 DISCOVERY REPORTS 



Genus Stylotellopsis, Thiele 



Stylotellopsis amabilis, Thiele. 



S. amabilis, Thiele, 1905, p. 456, fig. 72. 

 Occurrence. St. WS 27: South Georgia, 106-109 m.; St. WS 83 : Falkland Islands, 137-129 m. 



Distribution. Punta Arenas. 



Genus Raspaxilla, Topsent 

 Raspaxilla phakellina, Topsent. 



R. phakellina, Topsent, 1913, p. 617, pi. i, fig. 4, pi. vi, fig. 15. 

 Occurrence. St. WS 81 : Falkland Islands, 81-82 m.; St. WS 84: Falkland Islands, 75-74 m. 



Distribution. Burdwood Bank. 



Section HYMEDESMIEAE 

 Genus Hymedesmia, Bowerbank 

 Hymedesmia irritans, Thiele. 



Desmacidon ceratosa, Thiele, 1905, p. 435, fig. 56; Hymedesmia irritans, id., loc. cit., p. 455, 

 fig. 71. Nee Amphilectus ceratosits, Ridley and Dendy. 



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



Remarks. The present specimen has the form of a thin crust on a piece of coral. Its 

 structure is quite typical except that the sigmata and forceps are extremely rare. Also, 

 it may be noted that the acanthostyli are confined to those tissues immediately in con- 

 tact with the coral. 



From the observations made on the Discovery example of this species, it seems pro- 

 bable that Desmacidon ceratosa (Ridley and Dendy), Thiele, belongs to the same species. 

 Both are encrusting, both possess amphitylota and chelae of the same size and shape. 

 The differences between them rest in the absence of acanthostyli, sigmata and forceps 

 in D. ceratosa. Since it has now been shown that these three forms of spicules may be 

 either very rare or very inconspicuous, it is probable that more careful examination may 

 reveal their presence in those forms identified by Thiele as D. ceratosa. 



Hymedesmia, cf. laevis, Thiele. 



//. laevis, Thiele, 1905, p. 453, fig. 69. 

 Occurrence. St. 58 : Falkland Islands, 1-2 m. 



Remarks. The specimen agrees well with the holotype of Hymedesmia laevis, Thiele, 

 except that the tornota are mucronate at each end instead of simply strongylote. 



Distribution. Calbuco, Chile. 



