14 VEGETABLE ORGANOGRAPHY. 



Tubes {petits tubes), and has considered them as modifi- 

 cations of vessels ; but it is evident to any one who may 

 have observed them, that they are not vessels, because 

 they are closed at the two extremities ; — this is the rea- 

 son why, in the elementary principles placed at the head 

 of the third edition of the Flore Francaise, I have de- 

 scribed them under the name of Tubular Cellules 

 (cellules tuhulees), which indicates their form well 

 enough ; and I have given the name of Elongated 

 Cellular Tissue to that which is formed of them. 

 Rudolphi actually viewed them in the same light, 

 and described them under the name of Elongated 

 Cellules (cellules alongeesj. Mirbel has finished 

 by adopting the same opinion, and has described this 

 organ, when in a mass, at first under the name of 

 Woody Cellular Tissue (tissu cellulaire ligneux), 

 because he found it in abundance in wood ; and after- 

 wards under this of Elongated Cellular Tissue 

 (tissu cellulaire alongee). Treviranus has likewise coin- 

 cided in this opinion, and has given to these cellules 

 the name of Fibrous Utricules (utricules Jihreuses). 

 Cassini has called them Little Tubes (tuhilles). 



After the observations of Kieser and Dutrochet, it 

 appears to me, that two very different states of cellules 

 elongated in a longitudinal direction must be distin- 

 guished, viz : — 



1st. The Cellules ivhich enter into the composition of 

 loood and of the cortical layers. They have the appear- 

 ance of spindles, tapering to the two extremities 

 (PL 1, fig. 7) ; and Dutrochet has given them, from this 

 circumstance, the name of Clostres, which signifies a 

 spindle. 



These Clostres are commonly parallel to one another, 

 touching by their swollen parts ; and the intervals wliich 

 tlicy leave at their extremities are filled up by the points 



