FABRIC OF PLANTS. 



Doublings of spiral vessels in the balsam plant. a, a, a, remains 

 of the doublings in form of pores. 



" The annular vessels ' again, first described by 

 Bernhardi, are altogether different; being produced 

 by the rounds of a spiral tube becoming at first de- 

 tached and again united, to form a ring. The beaded 

 vessels 2 are only spiral vessels turned or folded with 

 narro wings at the foldings." 



Spiral, annular, and beaded vessels, magnified. 



(1) In Latin, Vasa annularia. 

 (2) In Latin, Vasa moniliformia. 



