I02 DISCOVERY REPORTS 



Generally distributed in all areas and at all depths down to 5029 m. It is very common 

 at St. WS 479, common at Sts. 171, WS 395 and 483, frequent at Sts. 192, 198, WS 384, 

 507 B, 515 and 517, more or less rare at the remaining stations. As a rule specimens are 

 small and not very typical, the best were found at Sts. 383, 385, WS 469, 507 B and 515. 



198. Trochammina globulosa, Cushman (Plate III, figs. 32-34). 

 Trochamtnina globulosa, Cushman, 1918, etc., FAO, 1920, p. 77, pi. xvi, figs. 3, 4. 



Ten stations: 177; WS 199, 468, 471, 495, 507 A, 507B, 515-17. 



Frequent to common at Sts. WS 507 A, 507B, 515, 516 and 517, very rare elsewhere. 

 The specimens are rather smaller than topotypes of Cushman's species from the West 

 Indies, with which I have compared them, but otherwise appear to be identical except 

 in their paler colour, due to a lesser proportion of ferruginous cement. The aperture 

 varies considerably in size, sometimes being large as in Globigerina bidloides, at other 

 times an inconspicuous crevice in the same position. 



The species is closely allied to Trochammina globigeriniformis, but the name may be 

 usefully employed to separate some of the kindred organisms usually assigned to that 

 species. Cushman's records were from the western shores of the North Atlantic, but the 

 species is probably widely distributed. 



199. Trochammina inconspicua, sp.n. (SG 139) (Plate III, figs. 38-40). 

 Trochammina turbinata, Earland non (Brady), 1933, SG, p. 86, No. 139. 



Forty stations : 169, 171, 177, 185, 191, 192, 196, 197, 203, 204, 206, 360, 362, 385; 64° 56' S, 

 64°43' W; WS 199, 203, 377, 383, 386, 387, 394, 471, 474, 479, 480, 485, 486, 494A, 495-7, 503, 

 507B, 509, 510, 515, 516, 552, 553. 



Test minute, free, thin walled and very fragile ; rounded in form, consisting of about 

 three convolutions in a low trochoid spire. Three to five rather inflated chambers, 

 rapidly increasing in size, form a convolution, all exposed on the dorsal surface, the 

 ventral side showing only the chambers of the final convolution. Aperture a small 

 arched opening on the inner edge of the final chamber. Sutures flush and inconspicuous, 

 the structure of the test being usually obscure except in balsam-mounted specimens. 

 Constructed of fine mineral grains with little cement. Colour pale yellowish grey. Size 

 very variable; average diameter about 0-15 mm., height about the same. 



This little organism, which was recorded in the South Georgia report under the name 

 T. turbinata (Brady) (SG 139), can no longer be regarded as a pauperate form of that 

 species, as its plan of growth is a regular trochoid spiral, while an examination of speci- 

 mens of T. turbinata from the type locality shows that the plane of convolution changes 

 during growth. In this respect it resembles the organism for which I have instituted the 

 new genus Recurvoides (see p. 90), and Brady's species must be transferred to that 

 genus as Recurvoides turbinatiis (Brady). 



Although widely distributed in the Antarctic Trochammina inconspicua is never very 

 common, and its fragility makes it difficult to obtain a series of perfect specimens. It is 

 less rare at Sts. 171, 191, 192, 196 and WS 383 than elsewhere. The range of depth 

 extends to 5029 m. at St. WS 553, but the majority of the records are in moderate 



