516 PTERIDOSPERMS, ETC. [CH. 



Gangamopteris kashmirensis, Seward. 



1905. Seward, Mem. Geol. Surv. India, Vol, ii. Mem. ii. 



This type agrees closely with G. cyclopteroides in size and 

 in the form of the leaf, but it is distinguished by the flatter 

 form of the arch formed by the lateral veins, by their greater 

 inclination to the margin of the lamina, and by the more 

 acutely pointed apex of the lamina. This species, though not 

 very sharply distinguished from G. cyclopteroides, is important 

 as coming from beds which have been assigned on other than 

 palaeobotanical evidence to an Upper or possibly a Middle 

 Carboniferous horizon ^ 



We have no definite information in regard to the nature of 

 the reproductive organs of Gangamopteris, but such evidence as 

 there is supports the view expressed by Dr White ^ and shared 

 by some other authors that Gangamopteris and Glossopteris 

 shotild be assigned to the Pteridosperms. Despite the abun- 

 dance of Gangamopteris leaves, no fertile specimen has been 

 discovered. This negative evidence may prove to be as correct 

 as that which led Stur^ to exclude Neuropteris, Alethopteris and 

 Odontopteris from the ferns. The only evidence of a positive 

 kind is that furnished by Dr David White in his recent Report 

 on the Palaeozoic Flora of South Brazil. This author describes 

 some small Aphlebia-like leaves under two new generic names 

 Arberia* and Derhyella^. The differences between the two sets 

 of specimen?!, so far as can be determined from the reproduc- 

 tions of imperfect impressions, are slight, and it is by no means 

 clear that a distinction of generic rank exists. These' scale- 

 leaves are on the average aboyit 2 cm. in length; the lamina is 

 oval or rounded and has more or less prominent lobes. In 

 Derbyella there are indications of anastomosing veins. The 

 specimens referred to Arheria minasica are, as White points 

 out, very similar to the fossil described by Feistmantel from 

 Lower Gondwana rocks of India as probably a portion of an 

 inflorescence of Noeggerathiopsis^. Feistmantel's specimen is 



1 Seward and Smith Woodward (05) ; (07=). 



■■i White (08) pp. 473, 483. 3 Stur (84) p. 638. 



* White (08) p. 587, PI. vm. figs. 8-10. ^ jjj^, p_ 543^ pi_ j^. figs. 1-3. 



8 Feistmantel (80) PI. xxvii. fig. 5. 



