242 



I'liliu rsil !i (if Cuiiforii'ui /'iil)lic(iiii>iis in liotdiu) [Voi,. 7 



coll niifilit serve as one of a iiuiulx'i- of bases for species dilfereiitiatioii 

 in Chriisofhdiiniiis. Cei'taiiily ('. hrrf ifolius (cf. |). 266) consistently 

 exhibits I'libber only in the foi-ni of lai'<:-e spliei'ical <i,-lobnles which 

 usually occnr sinj^ly and almost exclusively in the cells of the cortical 



y^^ 



Vig. *i. Portion of a cross-section ot" a mature loaf of ('liriisotluuuiius iiinisro»us 

 var. ronsiniilis. I'latit <rro\vii in tlio University of Califoi'iiia Botanical (iarden. 

 J-Jcrkclcy. Plioto-niici-ogi'apli. 



parenchyma. In the ikihscusus group a number of <»lobules often are 

 present in the cells of younjii: rubber bearing tissues but thej' tend 

 to a<i;j?l()merate with age so that the corresponding tissues when mature 

 show few if any globular rubber inclusions, this substance being 

 present in the "difTnsed" condition. Such a condition does not obtain 



