108 Proceedings of the Royal Physical Society. 



Triletes hi. pi. Ill, Fig. 3. 



Macrospore smooth, but not having a bright polished sur- 

 face as on I. and II. ; triradiate ridges very prominent and 

 short, and occupying only one-third of the upper surface. 

 A curved ridge connects the extremities of the arms of 

 the diverging ridges, but is not so much elevated as the 

 triradiate ridge itself. Occasionally a few feebly indicated 

 ridges radiate from the centre. 



Size. — 1*80 mm. to 1'42 mm. 



Horizon. — Calciferous Sandstone Series. 



Locality. — 10. 



Triletes IV. PL III., Figs. 4a, 45. 



Macrospore very small, outer surface feebly granulated. 

 Triradiate ridge prominent, occupying about four-fifths of the 

 upper surface, between the arms of which are radiating 

 flexuous lines that usually extend to the curved line that 

 connects the arms of the central three-rayed star. This is 

 the smallest fossil macrospore with which we have met. 



Size. — 0'57 mm. to 0'51 mm. 



Horizon. — Calciferous Sandstone Series. 



Locality. — 7. 



Division II. — Apiculati. 

 Outer surface of spore ornamented with mamillate spines, 

 and comparable to the macrospores of Selaginella hcematodes 

 (Fig. 24), or Isoetis echinospora (Fig. 25). 



Teiletes V. PL III., Figs. 5a, 55. 



Macrospore large, apiculate, though occasionally some indi- 

 viduals are almost smooth. Triradiate ridge occupying two- 

 thirds of the upper surface. Area between arms of ridge 

 finely apiculate; other portions of the outer surface bear 

 irregularly-distributed, somewhat distant mamillate spines. 



This form varies considerably in the quantity of the spines 

 it bears. Some specimens are almost smooth ; others have 

 only a small number of spines ; while many bear numerous 

 distant, irregularly-placed short conical spines. 



