MERIANOPTERIS. 



145 



lanceolate, narrowed slightly towards the apex, pinnatisect or 

 pinnatifid. Pinnules or lobes very delicate, rounded at the apex. 

 Median nerve distinct, somewhat curved towards the apex. 

 Secondary nerves arising at an acute angle, dichotomous, and 

 flexuous. The lowest pair of lateral nerves, arising from the 

 base of the median vein, dichotomise, and then arch to join the 

 corresponding nerves of the pinnules on either side. 



Feistmantel, in his original description, states that the two lower 

 lateral nerves of each pinnule "join with the same of the adjoining 



Fig. 34. — Merianopteris major, Feist. After Feistmantel. Nat. size. 



leaflets in a pointed arch." This union is not, however, clearly 

 shown in his figures. 



This frond presents an unusual type of nervation, and is 

 unfortunately only known from Gondwanaland by a few specimens 

 figured by Peistmantel from the Eaniganj group. Tenison- Woods, 1 

 however, has recorded this species from the Ballimore Coalfield of 

 New South Wales, apparently on a higher horizon, but I am not 

 convinced that his plant is either specifically or even generically 



1 Tenison-Woods (83), p. 114, pi. vi, figs. 2, 3. 



