176 DISCOVERY REPORTS 



As regards the other specimens, in which the two or more individuals, often of very 

 dissimilar sizes, are fused together by their shell substance, but without proximity of 

 apertures, it is still impossible to give any explanation of the phenomenon. But the 

 possibility that they are plastogamic unions cannot be overlooked in view of the recent 

 observations of E. H. Myers (M. 1933, MTF), who has estabUshed the existence of 

 plastogamic union between individuals of very different sizes, and in groups of more 

 than two individuals. In favour of this view is the fact that there is no miscegenation, 

 the attached specimens are always of the same species. 



456. Globigerina bulloides, d'Orbigny (F 304) (SG 276). 



Twenty-five stations: 167, 170, 175, 180, 181, 190, 360, 363, 366, 384-7; WS 204, 205, 389, 395, 

 403, 468, 469, 471, 482, 505, 515, 517. 



As might be expected, this species is most abundant at stations outside the Antarctic 

 convergence line. Large specimens are more or less common at Sts. 384, 385, 386, 

 WS 205, 403 and 469. But it is also widely distributed within the line, large specimens 

 being common at St. 204 in the South Orkneys, and frequent at Sts. 170, 180, 190 and 

 WS 482, all of which are affected by the warm Pacific water. At the remaining stations 

 it is more or less rare, often very rare. Its range, however, extends to the extreme south 

 of the BelHngshausen Sea, a few very good specimens having been found at St. WS 505, 

 near the ice barrier. 



457. Globigerina triloba, Reuss (F 305) (SG 277). 



Twenty-four stations: 187, 200, 201, 384-7; WS 203-5, 391-3, 403, 468, 469, 471, 472, 474, 482, 

 486, 488, 515, 517. 



Outside the Antarctic convergence line this species is frequent to very common at 

 most of the deep-water stations, and the specimens are large and typical. Within the line 

 it is common at St. WS 204 and frequent at St. 201 ; rare or very rare at the remaining 

 stations, most of which are in deep water. The species was not recorded at all by Wiesner 

 from Kaiser Wilhelm's Land, or in the Antarctic material of the Terra Nova Expedition, 

 though it was found in the New Zealand area. 



458. Globigerina triloba, Reuss, spinous var. (Plate VIII, figs. 13-15). 

 Two stations: 385 ; WS 204. 



A few specimens were found at these deep-water stations in which the early chambers 

 were covered with short strong spines. They are quite unlike the long and delicate 

 spines found on pelagic Globigerinae . The largest specimen was about 0-40 mm. in 

 diameter. 



459. Globigerina inflata, d'Orbigny (F 306) (SG 278). 



Eighteen stations: 170, 383-7; WS 204, 205, 392, 403, 468, 469, 471, 472, 502, 513, 517, 555. 



Apart from single specimens found at Sts. 170, WS 392 and 513 which are under 

 600 m., the species is confined to the deepest water, where it is dominant at Sts. 385, 

 386, 387, WS 204, 205, 468 and 469. It is frequent at Sts. 384, WS 403 and 472 ; rare 

 elsewhere. Thin-walled pelagic specimens were seldom seen, the general form being 

 smooth, thick-walled and benthic. At some stations, notably St. WS 205, small speci- 



