TETRAXONIDA 263 



Occurrence. St. 140: South Georgia, 122-136111.; St. 152: South Georgia, 245 m.; St. 190: 

 Palmer Archipelago, 93-130 m.; St. WS 80: Falkland Islands, 152-156 m. 



Distribution. Mediterranean ; Wilhelm Land. 



Sub-order STREPT ASTRO SCLEROPHORA 



Family PACHASTRELLIDAE 



Genus Pachastrella, Schmidt 



Pachastrella monilifera, Schmidt. 



(For synonymy see Burton, 1926, p. 9.) 



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



Distribution. Algeria; Mediterranean; Coast of Asturias; Cape Bojeador; Tristan 

 da Cunha ; Natal ; Agulhas Bank. 



Genus Poecillastra, Sollas 



Poecillastra compressa (Bowerbank). 



(For synonymy see Burton, 1930, pp. 487, 498.) 



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



Remarks. In two of the specimens the calthrops have undergone a considerable re- 

 duction and distortion, one or more of the rays being frequently reduced and those 

 remaining being variously knobbed at the ends or ornamented with tubercles and 

 spines. The condition closely resembles that of Stelletta pathologica, Schmidt, or Pach- 

 astrella abyssi (cf. Sollas, 1888, pi. xi, figs. 15-19). The distortion has extended to the 

 microxea also, although not to the same extent, and these are thicker, less markedly 

 roughened, but more strongly tylote than usual. 



Distribution. Arctic ; North Atlantic (east and west coasts) ; Mediterranean. 



Sub-order ASTRO SCLEROPHORA 

 Family GEODIIDAE 

 Genus Geodia, Lamarck 



Geodia magellani (Sollas). 



Cydonium magellani, Sollas, 1886, p. 197 ; id., 1888, p. 221, pi. xxi, figs. 1-14; Geodia magellani, 

 Lendenfeld, 1903, p. 107; Thiele, 1905, p. 408. 



Occurrence. St. WS 81 : Falkland Islands, 81-82 m. 



Distribution. Tom Bay, Caibuco and Admiralty Straits (South America). 



4-z 



