igo DISCOVERY REPORTS 



most typical examples were found at St. 175 in 200 m., but generally speaking the local 

 form is large and very compressed, the compression reaching its maximum at St. 177 in 

 1080 m., where some of the specimens were almost scale-like. Most of the records are in 

 moderate depths, but they extend down to 3762 m. at St. WS 471, where the single 

 specimen was entirely chitinous. 



517. Nonion boueanus (d'Orbigny) (F 405) (SG 336). 

 One station: 385. 



A single small specimen. 



518. Nonion sloanii (d'Orbigny) (F 403) (SG 334). 

 Two stations: WS 481, 482. 



One very good specimen at St. WS 481 , and a few small ones at St. WS 482. This, like 

 A'^. grateloupi, is normally a warm- water species. 



519. Nonion grateloupi (d'Orbigny) (F 406) (SG 337). 

 One station: 201. 



A single excellent specimen from 343 m. in the Bransfield Strait. This is generally 

 regarded as a warm- water species, and its occurrence so far south is noteworthy. 



520. Nonion scapha (Fichtel and Moll) (F 407) (SG 338). 

 Ten stations: 194; WS 383, 395, 476, 482, 487, 496, 506, 507 A, 507B. 



Rare or very rare everywhere, and the specimens are small and pauperate. The weak 

 variety named by Chapman N. scapha var. bradii (B. 1884, FC, pi. cix, fig. 16; C. 1914, 

 FORS, p. 71, pi. V, fig. 42) was observed at several stations but was not separated. 



521. Nonion pauperatus (Balkwill and Wright) (F 408). 

 Two stations : WS 395, 486. 



One very small specimen at St. WS 395 in 297 m., and another, exceptionally large, 

 at St. WS 486 in 787 m. Both stations are in the Bransfield Strait. 



Genus Nonionella, Cushman, 1926 



522. Nonionella iridea, Heron-Allen and Earland (F 410) (SG 339). 



Thirty-five stations: 162, 167, 180, 190, 194-6, 202, 203, 360, 362, 366, 369, 385; WS 383-5, 

 387. 391. 393. 395. 403. 476, 481-3. 485-7. 496, 497. 507B, 509. 5". 512. 



Common at Sts. WS 481, 482 and 487 and frequent at Sts. 162, 196, 203, WS 383, 

 485 and 486, but rare or very rare at other stations. The depths extend from shallow 

 water down to 3721 m., but very few specimens were observed at the deeper stations, 

 except at WS 383 (2085 m.). 



523. Nonionella turgida (Williamson) (SG 340). 



Seventeen stations: 170, 177, 190, 195, 196, 203, 369, 384; WS 383, 385, 476, 479, 481, 483, 

 485. 487. 510- 



Frequent at St. WS 487, rare or very rare elsewhere. 



Genus Elphidium, Montfort, 1808 



524. Elphidium incertum (Williamson) (F 412) (SG 341). 

 Four stations: 177, 180, 187; WS 498. 



