352 



CHALMER L, COOPER 



Test small, elongate, straight, tapering; 

 sarly chambers indistinct, may be bi- or 

 triserial, later chambers irregular in size and 

 shape, arranged alternately in oblique man- 

 ner; sutures distinct, sharply incised; apera- 

 ture terminal; diameter, 0.072-0.15 mm.; 

 length, 0.50 mm. 



This species, which is placed in synonymy 

 with Siphogenerina eleganta Plummer by 

 Cushman, is described as biserial by Plum- 

 mer and triserial by Cushman. The early 

 chambers of the Illinois specimen are too in- 

 distinct for accurate determination. It is 

 common in the upper Midway of Texas and 

 the lower Midway of Alabama. 



Family Ellipsoidinidae 



Genus Ellipsonodosaria A. Silvestri 



Ellipsonodosaria lepidula (Schwager) 



Plate 54, figure 23 



Nodosaria lepidula Schwager, 1866, Novara- 

 Exped. Geol. Theil., vol. 2, p. 210, pi. 5, figs. 

 27-28; Pliocene.— Galloway and Morey, 1929, 

 Bull. Am. Paleontology, vol. 15, no. 55, p. 17, 

 pi. 2, fig. 2; Eocene, Ecuador. — Galloway and 

 Morey, 1931, Jour. Paleontology, vol. 5, p. 

 337, pi. 38, fig. 1, Upper Cretaceous, Mexico. 



Ellipsonodosaria sp. Cushman, 1940, Cushman 

 Lab. Foram. Research Contr., vol. 16, p. 70, 

 pi. 12, figs. 1, 2; Midway group, Paleocene, 

 Alabama. 



Test elongate, tapering, straight; cham- 

 bers globular, smooth except that for lower 

 margin is angular, fimbriate; diameter, 

 0.078-0.17 mm.; length, 5 chambers, 0.55 

 mm. 



E. lepidula is distinguished by the globu- 

 lar, almost spherical chambers, which are 

 connected by short ''necks," and which are 

 smooth except for a very narrow fimbriate 

 margin on the lower edge. Rare in the late 

 Cretaceous of Mexico and the lower Mid- 

 way of Alat)ama. 



Ellipsonodosaria plummerae Cushman 

 Plate 54, figures 18, 19 



Ellipsonodosaria plummerae Cushman, 1940, 

 Cushman Lab. Foram. Research Contr., vol. 

 16, p. 69, pi. 12, figs. 4, 5; Midway group. 

 Pliocene, Texas. 



Test elongate, somewhat tapering, 

 straight; chambers pyriform, distinct, in- 

 creasing in size and becoming more pyri- 

 form upward, very spinose, especially at 

 ridge near base of chamber; aperture ter- 



minal, rounded, phialine; diameter, 0.078- 

 0.L3 mm., length, 5 chambers, 0.61 mm. 



This species seems very close to E. pseudo- 

 scripta Cushman from the Upper Cretaceous 

 and to E. sagrinensis (Bagg) from the Mid- 

 way. It differs from the latter, however, in 

 its more elongate chambers and from the 

 former by the more abrupt margins on the 

 lower edges of the chambers. 



Ellipsonodosaria sagrinensis (Bagg) 

 Plate 54, figure 22 



Nodosaria sagrinensis Bagg, 1912, U. S. Geol. 

 Survey Bull. 513, p. 58, pi. 16, fig. 4; Pliocene, 

 California. — Plummer, 1927, Texas Univ. Bull. 

 2644, p. 85, pi. 4, fig. 16; Midway group, Paleo- 

 cene, Texas. 



Nodogenerina sagrinensis Jennings, 1936, Bull. 

 Am. Paleontology, vol. 23, p. 187, pi. 3, fig. 17; 

 Hornerstown, Eocene, New Jersey. 



Test straight, tapered; chambers short to 

 globular in early stages, becoming more 

 elongate later, lower edge fimbriate, upper 

 part narrowing toward sutures, wall thickly 

 spinose; spines short above, longer below, 

 overhanging lower edge; sutures deep, 

 broad; average diameter, 0.10 mm.; length, 

 5 chambers, 0.50 mm. 



This species was placed in synonymy with 

 E. plummerae by Cushman (1940, p. 69) but 

 its chambers do not seem to be suflficiently 

 elongate to warrant its reference to that spe- 

 cies. It is abundant in the upper, but rare to 

 common in the lower Midway of Texas, and 

 has also been reported from the Navarro. 



Ellipsonodosaria spinulosa (Plummer) 

 Plate 54, figure 20 



Nodosaria spinulosa (part) Plummer, 1927, 

 Texas Univ. Bull. 2644, p. 85, pi. 4, fig. 19a, b 

 only; Midway, Paleocene, Texas. 



Test elongate, tapering, straight to 

 slightly arcuate; chambers somewhat elon- 

 gate, covered with spine-terminated ribs; 

 sutures depressed; average diameter, 0.10 

 mm.; height, 7 chambers, 0.50 mm. 



This form differs from Nodosaria spino- 

 costata n. sp. and from N. spinulosa Plum- 

 mer (1927, pi. 4, fig. 19c), in that its ribs 

 may terminate in spines over the entire 

 chamber wall while in N. spinocostata the 

 ribs occupy the entire length of the chamber 

 wall and terminate in a spine overhanging 

 the sutural depression. 



