20 



Harris (1961, p. 101-123, 140-185) illustrated 

 spores of the Granulatis pontes type from 

 compression fern fossils of Jurassic strata of 

 Great Britain. 



Granulatis pontes levis Kosanke, 1950 



The observed size, about 50 /x, given for 

 Granulatis pontes levis by Kosanke (1950, p. 

 21) is increased to include specimens up to 

 65 fx in diameter. 



Granulatis pontes deltiformis (Wilson & Coe) 

 Schopf, Wilson, & Bentall, 1944 



The several specimens of Granulatis pontes 

 deltiformis observed were similar to the speci- 

 men illustrated by Wilson (1958, pi. 1, fig. 9) . 



Granulatis pontes ibrahimi sp. nov. 

 Plate 2, figures 9-10 



Diagnosis. — The spores are radial, trilete, 

 and triangular in outline and have broadly 

 rounded corners and concave interradial 

 sides. The spores are in good proximal-distal 

 orientation. The trilete rays are equal in 

 length to the spore radius, and the lips are 

 poorly developed and usually not visible. The 

 proximal and distal surfaces of the spore coat 

 are covered with closely spaced spines that 

 usually are broader at their bases (up to 

 6.5 /x) than they are long (about 4.5 /x) . The 

 spines have pointed to slightly rounded ends 

 and are seldom curved or bent. Two spines 

 are occasionally joined in some part of the 

 spore coat and may sometimes form thick- 

 ened pads or area contagionis. Between 20 

 and 30 spines extend beyond the spore mar- 

 gin. The surface of the spore coat between 

 the spines is obviously levigate under oil im- 

 mersion objective. The exine is 1 to 1.5 /x 

 thick. Dimensions (25 specimens) : size range, 

 30.2 to 45.7 pi in maximum diameter (not in- 

 cluding ornamentation) ; median, 37.3 /x. 



Holotype. — Plate 2, figure 9; negative 6112; 

 Trivoli Cyclothem, maceration 1175-G, slide 

 21, coordinates, 143.6 X 33.3; size, 36.0 by 

 35.0 ii. 



Paratype. — Plate 2, figure 10; negative 

 6472; Trivoli Cyclothem, maceration 1175-G, 

 slide; 22, coordinates, 137.1 X 35.5; size, 36.7 

 by 32.5 /x. ' , , 



(Umipar'uon-.- J r- T Y\w, spines of Granulati- 

 sporites ibrahimi arc less sharply pointed and 



less strongly curved than those of Acantho- 

 triletes falcatus (Knox) Potonie & Kremp, 

 1955. G. ibrahimi has larger, fewer coni 

 than G. gibbosus (Ibrahim) Schopf, Wilson, 

 & Bentall, 1944, G. microsaetosus (Loose) 

 Schopf, Wilson, & Bentall, 1944, and Lo- 

 photriletes mosaicus Potonie & Kremp, 1955. 

 G. ibrahimi is more triangular and usually 

 smaller than L. insignitus (Ibrahim) Potonie 

 & Kremp, 1955. 



Derivation of name. — The species is named 

 in honor of Dr. A. G. Ibrahim. 



Granulatis pontes tenuis sp. nov. 

 Plate 2, figures 11-12 



Diagnosis. — The spores are radial, trilete, 

 and triangular in outline. The corners op- 

 posite the rays are rounded, and the inter- 

 radial sides are straight to slightly convex or 

 concave, depending upon the manner of 

 compression. The spore coat is thin and usu- 

 ally folded during compression. The com- 

 missure is distinct, straight, extends to the 

 spore margin, and generally is open. Lips 

 are absent. A narrow, slightly thickened con- 

 tact area is present along the aperture and 

 extends almost to the ends of the rays. The 

 surface of the spore coat is discernibly levi- 

 gate under oil immersion objective. The 

 exine is 1 to 1.5 /x thick. Dimensions (17 

 specimens) : size range, 23.3 to 33.0 /x in 

 maximum diameter; median, 28.2 /x. 



Holotype. — Plate 2, figure 1 1 ; negative 

 6473; Fithian Cyclothem, maceration 1170-A, 

 slide 10, coordinates, 125.9 X 45.9; size, 32.8 

 by 28.3 /x. 



Paratype. — Plate 2, figure 12; negative 

 6141; Trivoli Cyclothem, maceration 1175-C, 

 slide 24, coordinates, 131.6 X 50.4; size, 26.9 

 by 24.0 ix. 



Comparison. — Granulatisporites tenuis is 

 thicker and less angular than Leiotriletes 

 directus Balme & Hennelly, 1956, which lacks 

 well defined contact areas. G. tenuis is simi- 

 lar to Laevigatis pontes minimalis Dybova 

 & Jachowicz, 1957, but the latter has rays 

 three-fourths the length of the radius, and 

 apparently possesses no darkened contact 

 areas. G. tenuis differs from Leiotriletes gula- 

 ferus Potonie & Kremp, 1955, in having dark- 

 ened contact areas along the rays and usually 

 in being smaller. G. tenuis, unlike L. gula- 

 ferus, is not consistently folded along one of 



