FLORA OF THE KOOTAXIK FORMATION. 289 



;iii(l :i thick, app.-irciilly coriaceous loaf siihstaiico that loaves a iiliu 

 of cai'hoii on the fock. Th(> foi'tilo spocimons ai'o such as \v(> should 

 oxpoct to 1)0 found if the storilo piuiuil(^ dopictcnl in PI. TAXI, I'lp. "), 

 undorwont such modifications as ai'o found in the fertile pinnules of a 

 Dick.sonia. The two fcM'tilo portions of piiuuili^s <z;iven in PI. LXXI, 

 Figs. 7 and 9, differ decidedly from the foi-tilo pinnules of I). iiionUi- 

 'ncnsis. and this fact has induced me to make, hut with doubt, a new 

 species of these forms. The material is much too imperfect and scanty 

 to poi'init their proi)er place to 1)(> determinctl with any degree of 

 positiveness." 



The form given in PI. LXXI. V\g. 7, differs .somewhat from that 

 shown in ]''ig. fl, hut tli(> difference is of the same nature as that shown 

 in \hv two fertile forms of Dicksotria mnnlauohsis; that is, the form 

 shown in Fig. 7 is moi'e modified and less foliaceous than that given 

 in Fig. 9. 



The sterile form depicted in PI. LXXF Fig. o, is the fragment al 

 terminal portion of what must have been a rather large pinnule. It 

 reminds one somewhat, in size and nervation, of the sterile piimules 

 of the living Dicksonin sor1){folia Smith; onh' the terminal portion of 

 the piimule is preserved to such an extent as to give some idea of its 

 shape. The lamina on the left side of the lower part of it is wholly 

 wanting, and on the corresponding right-hand portion the margin is 

 gone, so that we can not determine whether or not the lower portion 

 of the pinnule had dentate margins like the upper portion. It prob- 

 aljly had. 



The lateral nerves are strong and in all parts of the pinnule foi-k 

 neai' their departui'e from the midrib. In the lower part of the pin- 

 nule not enough is shown to disclose certainly the entire course of these 

 nei'ves. but one, on both of the branches, apparently forks again. In 

 the terminal toothed portion there is no secontl forking and each branch 

 terminates in a tooth, as is shown in the magnifiefl portion, PI. LXXI, 

 Fig. 6. 



The fragment represented in PI. LXXI, Figs. 7 and 8. is a small 

 bit of a fertile pinnule with relatively large sori, placed close to the 



" Better material was obtained from t lie Slmstu formal ion described later by Professor Fontaine, but inserted 

 earlier in this paper. — L. F. W. 



HON XLViii — 0.5 19 



