252 ll'FER CRETACEOUS-LOWER TERTIARY FORAMINIFERA 



the Eocene of the mid-Pacific sea mounts (Hamilton 1953) and the Paleocene 

 Salina and Pale Greda formations of Peru (Weiss 1955a, b). 



In the Esna-Idfu region, G. wilcoxensis appears at the top of the G. velascoensis 

 Zone as a rare form which crosses the Paleocene-Lower Eocene boundary, and 

 increases gradually upwards in the section to flood the basal part of the Eocene, 

 characterizing the Globorotalia wilcoxensis Zone. 



Globorotalia woodi sp. nov. 



(PI. 23, figs. 2<z-c) 



Diagnosis. A Globorotalia with small, umbilico-convex test ; chambers which 

 increase rapidly in size ; narrow umbilicus ; long, narrow aperture ; curved, depressed 

 dorsal sutures and slightly curved, incised ventral ones ; delicate but distinct 

 marginal keel ; delicately papillose surface. 



Description. Test small, umbilico-convex, coiled in a low trochospire ; dorsal 

 side almost flat, although the early chambers are slightly raised ; ventral side distinct- 

 ly protruding ; equatorial periphery ovoid, elongate, slightly lobate with a delicately 

 beaded marginal keel ; axial periphery angular, acute ; chambers on the dorsal side 

 are not all clear because of the surface rugosity, but appear to be 11 in number, 

 arranged in 2 sinistrally coiled whorls ; the last whorl is composed of 5 relatively 

 large crescentic chambers, which increase rapidly in size ; on the ventral side, the 

 chambers are 5, roughly triangular, angular conical, increasing rapidly in size ; 

 sutures on the dorsal side curved, delicately beaded, and slightly depressed ; on the 

 ventral side they are slightly curved and strongly depressed ; umbilicus extremely 

 small, moderately deep and open ; aperture interiomarginal, extraumbilical-umbilical, 

 a long, narrow arch, with a narrow delicate lip ; wall calcareous perforate ; surface 

 rough papillose, with the roughness decreasing gradually towards the last chamber. 



Dimensions of holotype. 



Maximum diameter = 0-27 mm. 



Minimum diameter = 0-21 mm. 



Thickness = 0-15 mm. 



Remarks. Globorotalia woodi sp. nov. is morphologically similar to both Globo- 

 rotalia planoconica Subbotina and Globorotalia pseudoscitula var. elongata Glaessner. 

 It differs from the former in having a slightly larger test, more protruding ventral 

 side, slightly curved ventral sutures, well-developed marginal keel, and rough surface. 

 It is distinguished from G. pseudoscitula var. elongata Glaessner by its well developed 

 marginal keel, sharply angular axial periphery and rough surface. 



Globorotalia woodi is believed to have evolved from G. emilei sp. nov. either 

 directly or indirectly through its descendant G. pseudomenardii Bolli by flattening of 

 the dorsal side and greater protrusion of the ventral, and by the development of a 

 more tightly coiled test, rough surface and a delicately beaded keel. 



This species is named after Professor Alan Wood, U.C.W., Aberystwyth. 



Holotype. P.45616. 



