44 



radius. A triradiate ridge, 3 to 4 /x wide, is 

 joined to the thickened equatorial zone. This 

 zone is dense and almost opaque, and its 

 thickness tapers toward the poles. In speci- 

 mens that are obliquely compressed, the in- 

 ner margin of the thickened zone may be 

 sharply delineated. The zone is divided into 

 two parts by a concentric groove running 

 parallel to the margin. The proximal and 

 distal surfaces of the spore body and equa- 

 torial zone are covered with widely spaced 

 puncta or vermiculations. Shallow vermicula- 

 tions connect two or more distinct, deep 

 puncta that are 1 fi or less in diameter. The 

 proximal and distal surfaces of the spore coat 

 between the pits and vermiculations are mi- 

 nutely punctate as viewed under oil immer- 

 sion objective. Dimensions: size range, 37.6 

 to 56.4 /.t in maximum diameter. 



Figured specimen. — Negative 6121; Hen- 

 shaw Formation, maceration 1122-A, slide 

 44 ZB, coordinates, 134.0 x 41.5; size, 56.4 

 by 50.2 /x. 



riphery of the spore. The spore coat is about 

 1.5 [l thick. 



Figured specimen. — Negative 6475; Hen- 

 shaw Formation, maceration 1122-Q, slide 

 2, coordinates, 138.6 X 51.6; size, 35.1 by 

 29.9 /x (not including ornamentation). 



Spore E 

 Plate 8, figure 3 



The spore is radial, trilete, triangular in 

 outline, and has convex interradial sides. The 

 commissure is distinct, and the rays are 

 straight and equal in length to the spore 

 radius. The spore coat is covered with a 

 reticulate ornamentation in which the muri 

 are 2 to 3 /* wide by about 3 /x high and 

 the lacunae are 3 to 4 ju in diameter. The 

 exine is about 1.5 /x thick. 



Figured specimen. — Negative 5479; Hen- 

 shaw Formation, maceration 1122-Q, slide 9 

 ZB, coordinates, 124.1 x 43.7; size, 41.3 by 

 38.3 p. 



Spore G 



Plate 8, 



figure 1 



The spore is radial, trilete, triangular in 

 outline, and has well rounded corners. The 

 rays are distinct, straight, and extend to the 

 inner margin of the thickened equatorial 

 zone. This zone, 9 to 10 /x wide (slightly 

 wider at the corners) , is shingle-like and 

 thickest toward the inner margin. The outer 

 margin of the zone is irregular and notched. 

 The main body has shingled thickenings, es- 

 pecially adjacent to the rays, and the proxi- 

 mal surface is discernibly punctate under oil 

 immersion objective. 



Figured specimen. — Negative 5585; Hen- 

 shaw Formation, maceration 1122-A, slide 

 16 ZB, coordinates, 130.8 X 42.3; size, 64.9 

 by 63.3 /x. 



Spore D 

 Plate 8, figure 2 



The spore is radial, trilete, triangular in 

 outline, and has well rounded corners. The 

 indistinct rays extend to the spore margin. 

 The spore coat is ornamented with very 

 closely spaced, clavate projections about 3 /x 

 long and 2 to 3 (i wide at their ends. From 

 50 to 60 projections extend beyond the pe- 



Spore F 

 Plate 8, figure 4 



The spore is radial, trilete, triangular in 

 outline, and has greatly expanded corners. 

 The trilete rays are distinct, straight, and 

 about two-thirds the length of the spore ra- 

 dius. Pyramidal areas are darker and thicker 

 than the rest of the spore coat. Under oil 

 immersion objective, the surface of the spore 

 coat is distinctly granular. The exine is about 

 2.5 n thick. 



Figured specimen. — Negative 5605; Hen- 

 shaw Formation, maceration 1122-A, slide 

 22 ZB, coordinates, 123.1 X 48.6; size, 59.4 

 by 59.0 t Li. 



Spore G 



Plate 



5, figure 5 



The spores are radial, trilete, broadly tri- 

 angular in outline, and have a scalloped mar- 

 gin. The rays are distinct and extend to the 

 margin of the spore body. The spore body 

 is surrounded by a broad, contorted flange 

 that is usually widest at the corners. Broad, 

 branching ridges are present over the distal 

 surface of the body and flange. Under oil 

 immersion objective, the surface of the body 

 and flange appear finely granulate. Dimen- 

 sions: 25 to 40 fi in maximum diameter. 



