NO. 1 CUSHMAN, MCCULLOCH : ARENACEOUS FORAMINIFERA 101 



Length up to 3.50 mm ; diameter 0.25-0.30 mm. 



This species may be distinguished from the preceding by the smoother 

 test without depressed areas at the sutures and the triserial stage shorter 

 with the sutures indistinct. It occurs at the following stations: 487, 

 482, 475, 579. 



Distribution. — Off Tower Island in 175 fms. ; in Cartago Bay, 

 Albemarle, in 250 fms. ; off Chatham, in 400 fms. ; off Peru, in Sechura 

 Bay, in 12 fms. 



Family Trochamminidae 



Genus TROCHAMMINA Parker and Jones, 1860 



Trochammina kellettae Thalmann 



Plate 11, Fig. 1 



Trocha??i?nina peruviana Cushman and Kellett, Proc. U. S. Nat. 

 Mus., vol. 75, art. 25, 1929, p. 4, pi. 1, figs. Sa, Z*.— Cushman and 

 Parker, 1. c, vol. 80, art. 3, 1931, p. 6, pi. 2, figs. 7a-c. — Bermudez, 

 Mem. Soc. Cubana Hist. Nat., vol. 9, 1935, p. 176. 



Trochammina kellettae Thalmann, Eclog. Geol. Helv., vol. 25, 

 no. 2, 1932, p. 313. 



Test trochoid, spire greatly flattened, dorsally very slightly convex, 

 ventrally slightly concave, consisting of three or four whorls; chambers 

 numerous, 10 or more in the last- formed whorl, of rather uniform size 

 and shape increasing slowly in size as added ; sutures on the dorsal side 

 gently curved, very slightly depressed, only those of the last-formed 

 whorl distinct, on the ventral side gently curved or with a sinuous, lobed 

 condition especially in later portions, distinct; wall finely arenaceous 

 with much chitin, thin, very flexible when wet; aperture ventral, along 

 the inner margin of the last-formed chamber. 



Diameter 0.25-0.40 mm. 



This species was originally described from off Eten, Peru. The ven- 

 tral side has peculiar lobes on the edge of the chambers and in spite of 

 its small size this seems to be a distinctive species, rather widely dis- 

 tributed. It occurred at the following stations: 215, 210, 241, 238, 222, 

 252, 244, 239, 232, 256. 272, 280, 257, 299, 292, 275, 2000, 577, 523, 

 537, 572, 554, 566, 579, 2067, 2059, 2066, 530, 531, 557, 76, 319, 

 458, 2049, 2003, 2019, 2037, 410. 



Distribution. — Widely distributed, with station records showing a 

 range from Peru northward to San Pedro, California. 



