FLORA OF THE KOOTANIE FORMATION. 287 



linear in shape and are cut down nearly to the midrilj into strap-shaped 

 lacinise that bear sori at their ends, where they are slightly broader than 

 in their other portions. The width of these pinnse near their base is 

 about 3 mm., and they narrow slightly toward their tips. None of them 

 were seen entire, but they were apparently a little over 2 cm. in length. 

 Both the midnerve and the lateral nerves seem to have been slender and 

 could not be distinctly seen. The sori at the ends of the lacinise are 

 comparatively large and appear to be opened by the pressure of the rock 

 matter so as to expose their upper surface. They are more or less 

 rounded in form and slightly depressed in their central portions, so as to 

 appear saucer shaped. No central column, as in Thyrsopteris, was seen 

 in the sori, but the sporangia appear to have been scattered over the 

 whole of their upper surface. The sporangia were proportionally quite 

 large, as the pits left by them are to be distinctly seen with the help of a 

 good lens. The pitting caused by the falling out of the sori produces a 

 sort of granulation on the upper surface of the sori. The appearance 

 presented now l^y the sori on these forms suggests the idea that they are 

 compressed so as to open the valves of the involucre, if this existed, and 

 expose the parts contained within them. 



In some specimens, such as that shown in PL LXXI, Fig. 3, of which 

 an enlarged pinnule is shown in Fig. 4, the metamorphosis of the pinnse 

 seems to be carried farther and little appearance of a foliaceous nature 

 is shown. These pinnse are cut down rather more deeply and no differ- 

 ence is shown l^etween the lacinise toward their bases and those higher 

 up. The lacinise are more narrowed and thickened than in Fig. 1 and 

 look like pedicels. They are slightly broader at their summits, where 

 they carry the sori. The narrowed lacinise with the sori look like clubs. 

 These pinnse, so far as seen, are a little less than 3 mm. wide. They are 

 about 2 cm. long and are linear in foi'm. They are inserted on the main 

 rachis as are those shown in PI. LXXI, Fig. 1, and like them are slightly 

 decurrent. The sori borne at the summits of the lacinise are, in these 

 pinnules, rounded or sometimes slightly reniform. They present a smooth 

 surface and show more of the indications of sporangia than are to be seen 

 in the forms depicted in PL LXXI, Fig. L If, as is probable, the sori 

 are furnished with a 2-valved involucre, as in Dicksonia, the forms 

 represented in Fig. 2 show them with the valves closed and exposing 

 only the outer surface of one of the valves. 



