BENNETTITES. 



155 



Ehagtic. 

 Jurassic. 

 Cenomanian. 

 Inferior Oolite. 



Middle Cretaceous. 



Neocomian. 



Potomac. 



Dakota. 



Cretaceous. 



Kach (Umia beds; Up. Oolite). 



Eajniahal (Lias). 



SWEDEN (SCANIA). W. angustifolia, Nath. 

 BORNHOLM. W. Forchhamnuri, Nath. 

 GREENLAND. W. cretacea, Heer. 

 ITALY. W. (Blastolepis) otozamitis, Zig. 



W. (Blastolepis) falcata, Zig. 



W. (Blastolepis) acuminata, Zig. 

 CANADA. W. recentior, Daws. 



Williamsonia ? 

 AMERICA. W. virginiensis, Font. 



W. elocata, Lesq. 



W. ? Xiesii, Hollick 

 INDIA. 1 W. Blanfordi, Feist. 



W. cf . gigas, Carr. 



W. microps, Feist. ,, ,, 



The second English species, W. Leckenbyi, is founded on a small 

 rayed disk like the large " carpellary disk" of Williamson, and 

 is regarded by Saporta as a lobed terminal expansion and not an 

 involucre as suggested by JSTathorst. Saporta considers it possible 

 that the forms referred to this species may be simply a "morpho- 

 logical variation " 3 of W. gigas. 



Buckland's Podocarya is transferred by Saporta to Williamsonia, 3 

 and it is highly probable that this plant is a bennettitean in- 

 florescence. 



The French species W. Pougneti, Sap., 4 is founded on an 

 imperfect specimen which does not admit of any exact determina- 

 tion, and hardly justifies the institution of a new species. W. 

 Zeilleri, Sap., 5 is also founded on a very poor specimen, and cannot 

 be diagnosed with any exactness. W. minima, Sap., 6 recently 

 described from Portugal, is represented by an imperfect cluster 

 of small bracts, and cannot be accepted as a satisfactory record 

 of the genus. 



Saporta has pointed out that Heer's species, W. cretacea, from 

 Greenland, shows many points -of divergence from the typical 



1 A fossil figured by Sharpe as Asterophyllites ? from South Africa resembles 

 an involucre of Williamsonia ; but Hooker's description of the specimen is more 

 suggestive of such a genus as Schizoneura (Sharpe, Trans. Geol. Soc. vol. vii. 

 [2], p. 227). I am indebted to Prof. Eupert Jones for calling my attention to 

 Sharpe' s figure. 



2 Saporta, Pal. Franc, vol. iv. p. 167. 3 Ibid. p. 127. 



* Ibid. p. 124, pi. ccxxxvii. ; see also Saporta and Marion (2), vol. i. p. 234. 



5 Ibid. p. 181, pi. ccxxxiv. fig. 3. 



6 Saporta (1), p. 105, pi. xix. fig. 9. 



