358 MULTIPLICATION. 



occur ill other Arads as Arwm inaculatamf Hlchardia 

 cethiopicay and Anthnrium Scherzerianum, frequently 

 combined with a leaf-like appearance of the spathes 

 and sometimes with a subdivision of the spadix into 

 two or three branches. 



Engelraann relates the occurrence of an increased 

 number of glumes in Bromus velutinus associated with 

 suppression of the flowers. 



Polyphylly. As previously explained, this term is 

 here applied to those cases in which the members of 

 any particular whorl are increased in number, the 

 whorls themselves not necessarily being augmented. 



The simplest cases of this kind are those in which we 

 meet with an unusual number of leaves in a whorl. 



Increased number of leaves in a whorl. This may arise 

 from actual multiplication, or from lateral chorisis, or 

 fission. The true nature of the case may usually be 

 ascertained by an examination of the distribution of 

 the veins of the leaves, or of the fibrous cords of the 

 stem, by the relative position of the supernumerary 

 organs, &c. 



Among plants with normally opposite leaves the 

 following occasionally produce them in whorls of 

 three : Louicera hrachypoda, L. Xylosteum, Weigela 

 rosea, Cornus mas, Vinca minor, &c. 



Paris quadrifolia may frequently be met with with 

 five leaves in its whorl, or even six.^ 



Increased number of bracts. This is not of infrequent 

 occurrence ; one of the most curious instances is that 

 recorded by Mr. Edwards^ in Cerastium glomeratum, 

 where, in place of the usual pair of bracts at the base 

 of the head of flowers, there was a whorl of six or eight, 

 forming an involucre. The flowers in this case were 

 apetalous and imperfect. 



Polyphylly of the calyx. This may occm' without any 



' See Henslow. ' Mag. Nat. Hist.,' 1832, vol. v, p. 429. 

 ' ' Phytologist,' September, 1857. 



