No. 449.] NORTH AMERICAN CONIFER ALES. 359 



abruptly and permanently. Among fossil plants — except the 

 genus Pityoxylon which, being essentially Pinus, falls under the 

 general rule — there is no instance of such structures outside qf 

 the four genera named, save in the case of the remarkable 

 Sequoia bnrgessii, from the Lignite Tertiary (4, p. 242) and 5. 

 penhalloivii of Jeffrey. As it will be necessary to further dis- 

 cuss the essential structure of the fusiform ray when considering 

 the resin passages in particular, it will be unnecessary to deal 

 with it more at length at the present moment. 



Page 249. For Cordaite^/ read Cordaitej-. 



Page 263, Fig. 12. For Radial read Tangential. 



