STRUCTURE OF FRUIT. 171 



Hispanicus, the bracts, from the axils of which the 

 flowers are developed, surround the ovary so closely and 

 are united to it in such a manner as to seem an integrant 

 part of the fruit ; it is tin's which caused Gsertner to 

 give it the name of Scolymus angiospermus. 



In Echinops, the bracteoles, which collectively form 

 the involucellum, perform the part of a calyx towards the 

 ovary, being united with it and forming a kind of false 

 scaly pappus. 



In Lagasca, the involucellum surrounds the achenium 

 without adhering to it, and seems to be a cup-like calyx 

 around the pericarp. 



In all the Compositae and Dipsaceae with a double 

 involucrum, the bracts, which form the involucellum or 

 proper involucrum of the flowers, present, more or less 

 distinctly, analogous phenomena. 



Lastly, to mention other families, the bracts of 

 Pollichia become fleshy after flowering, and are easily 

 taken for an integrant part of the fruit, which they 

 cover ; the foliaceous involucrum of the Hazel seems to 

 form part of the fruit ; the cup of the Acorn is a true 

 involucrum formed by the union of a great number of 

 little bracts, and the Acorn, like the Nut, is a fruit 

 formed by an ovary adherent to the calyx. These two 

 examples present a rare peculiarity in the vegetable 

 kingdom, viz. : — a fruit which adheres by a large portion 

 of the base, which at the time of separation caused a great 

 cicatrice like that which is most commonly seen in 

 seeds. This cicatrice of the fruit, or Carpal Cicatrice, 

 ought to be distinguished from that of seeds, or the 

 hilum, of which we shall shortly speak. 



The peduncles themselves sometimes seem to form 

 part of the fruit; thus, in Semecarpus and Anacardium, 

 they enlarge after flowering, become fleshy, and take 

 the form of a Pear, whilst the true fruit, which is dry, 



