25 



slide 22, coordinates, 126.4 x 38.4; size, 32.2 

 by 25.0 ii. 



Paratype. — Plate 3, figure 10; negative 

 6108; Henshaw Formation, maceration 1122- 

 Q, slide 46 ZB, coordinates, 139.9 X 34.6; 

 size, 31.4 by 26.2 fi in diameter. 



Comparison. — Laeuigatos pontes papillatus 

 is somewhat similar to Punctatosporites grani- 

 fer Potonie & Kremp, 1956, but is papillate 

 rather than granulose and is less coarsely 

 ornamented. 



Derivation of name. — The species name 

 refers to the papillate (papillatus) ornamen- 

 tation. 



FIG. 5 — Diagrammatic detail of portion of exine 

 of Laevigatosporites spinosus sp. nov. 



Laevigatosporites spinosus sp. nov. 

 Plate 3, figures 11-12; text figure 5 



Diagnosis. — The spores are bilateral, mono- 

 lete, and elliptical in outline. The margin 

 of the spore is slightly scalloped due to the 

 ornamentation. The distinct, straight commis- 

 sure is usually open and almost equal in 

 length to the long dimension of the spore. 

 The spore coat is covered with thick spines, 

 about 1.5 /x in length and diameter, that have 

 gently rounded ends. Two or three spines 

 commonly are connected by low irregular 

 ridges. On top of each major spine is a 

 smaller, thin, almost transparent, sharp spine 

 about 1 /x long (text fig. 5) . In cross section, 

 under oil immersion objective, the thin spines 

 are barely visible, but in face view they ap- 

 pear as sharp, distinct points. The major 

 spines are 1 to 2 tt apart, and about 35 can 

 be counted along the spore margin. The spore 

 coat is about 2 tt thick. Dimensions (15 

 specimens) : size range, 16.2 by 12.9 tt to 

 22.7 by 17.8 /x (not including ornamenta- 

 tion) ; median, 19.2. by 15.2 p. 



Holotype. — Plate 3, figure 1 1 ; negative 

 6109; Henshaw Formation, maceration 1122- 

 Q, slide 29 ZB, coordinates, 141.7 X 43.0; 

 size, 22.4 by 18.5 /*. 



Paratype. — Plate 3, figure 12; negative 

 6465; Henshaw Formation, maceration 1122- 

 Q, slide 11 ZB, coordinates, 139.2 X 45.7; 

 size, 19.8 by 15.6 [x (not including ornamen- 

 tation) . 



Derivation of name. — The species name re- 

 fers to the spinous (spinosus) spore coat. 



Genus Latipulvinites gen. nov. 

 Plate 3, figures 13-14; text figure 6 



Type species. — Latipulvinites kosankii. 



Diagnosis. — The generic name Latipulvi- 

 nites is proposed for small spores having the 

 following characteristics. The spores are ra- 

 dial, trilete, triangular in outline, and usually 

 in good proximal-distal orientation. They 

 have well rounded corners and straight to 

 slightly concave or convex interradial sides. 

 The distinct, straight, trilete rays that extend 

 to the spore margin have very narrow, slightly 

 elevated lips. The spores possess prominent 

 triradiate ridges. The flat-crested ridges are 

 thickest toward their outer, sharply delineated 

 margin; they extend about half the distance 

 to the interradial spore margin and at least 

 two-thirds of the distance to the corners op- 

 posite the rays. The spore coat, about 3 //, 

 thick, is discernibly levigate under high dry 

 objective. The known size range is 38.9 to 

 48.6 p. 



Discussion. — Latipulvinites is distinguished 

 from other small spore genera by its triangu- 

 lar shape and well developed triradiate ridges 

 (text fig. 6) . Some specimens of Latipul- 

 vinites that have small folds extending from 

 the corners opposite the rays to the ends of 

 the triradiate ridges give the gross appearance 

 of Ahrensis pontes. However, the kyrtomes of 

 Ahrensis pontes, unlike the elevated structures 

 of Latipulvinites, are on the distal spore sur- 

 face. Some species of Granulatis pontes with 

 thickened contact areas, for example G. levis 

 Kosanke, 1950, are somewhat similar to Lati- 

 pulvinites but do not have the well developed 

 triradiate ridges of Latipulvinites. 



Affinity. — Unknown. Probably filicinean. 



Derivation of name. — The genus is named 

 Latipulvinites because of its wide (latus) , 

 cushionlike (pulvinus) triradiate ridges. 



