110 PROF. A. C. SEWAED OX WEAiDEX ELOEAS. [March 1913, 



plants agreeing generally with Mantell's type, though by no means 

 in all cases specifically identical Avith the species on which the 

 records are founded. Similarl}' Araucarites pijjpingfordensis and 

 Pinites sohnsi 1 represent respectively Araucarian and Abietineous 

 plants accredited to different regions, on evidence furnished by 

 identical or closely-allied species. 



In addition to the regions named at the head of the table, there 

 are a few others from which Xeocomian species have been recorded ; 

 but the number of such specimens is small, and the floras are not 

 sufficiently important to be included in a general summary which 

 is admittedly incomplete. A few plants have been described by 

 Prof. Wathorst - from jSeocomian rocks in Mexico, and it is possible 

 that a few species recorded from IS"ew Zealand 3 are members of a 

 Wealden flora. Xeocomian species have been described from South- 

 western China, 4 and an imperfectly-preserved specimen from Egypt 

 is compared with WeicJiselia mantelli." 



The age of the Spitsbergen and Kiug-Charles-Land plants is 

 considered by Prof. Nathorst to be Uppermost Jurassic, the term 

 'Jurassic' being understood to include Wealden floras. 6 It is 

 generally recognized that, botanically, the limit between Jurassic 

 and Cretaceous floras, using the terms in the ordinary strati- 

 graphical sense, is largely conventional. 7 Prof. Nathorst also 

 assigns the plants described by him from Franz Josef Land to the 

 upper part of the Jurassic System." 



From Bornholm a few plants have recently been described 9 as 

 probably Wealden in age, although the great majority of species 

 from that island are from a Liassic or even llhsetic horizon. 



The material described by Neumann, Zeiller, and Salfeld 10 from 

 Peru, though small in amount, indicates the presence of a Wealden 

 flora. 



In Eastern North America 11 the Potomac Group, or at least the 

 older plant-beds, have afforded a particularly rich harvest of Lower 

 Cretaceous or Cretaceo-Jurassic types. On the west side are the 

 Kootanie plants (Montana), the Shasta flora (California), the plant- 

 beds in the Queen Charlotte Islands, and other floras described by 

 several authors. 



1 The Middle Cretaceous species Prepinus stafenensis Jeffrey from Kreisch- 

 erville, New York, is probably a closely allied type. See Hollick & Jeffrey 

 (<J9) p. 19. 



2 Wathorst (90 2 ). 3 See Seward (94) p. xxxiii. 

 4 Yokoyama (06). 5 Seward (07 2 ). 



Natborst (97) ; id. (10) p. 369. See also Gotban (07). 

 < Van den Broeck (01) p. 199. On this subject, see an important note by 

 Mr. Lamplugh (00). 



» Nathorst (99). 3 Bartholin (10). 



10 Neumann (07); Zeiller (10); Salfeld (09). 



11 For references, see Berry (ll 2 ) : also Knowlton (10) ; Cbamberlin & 

 Salisbury (06) -vol. iii, cbap. xiv. 



